Browse Topic: Cold start

Items (333)
Find
Study of Flash Boiling Spray Combustion in a Spark Ignition Direct Injection Optical Engine Using Digital Image Processing Diagnostics2019-01-02524/2/2019
Flash boiling spray has been proven to be a useful method in providing finer fuel droplet and stronger evaporation in favor of creating a homogeneous fuel-air mixture. Combustion characteristics of flash boiling spray are thus valuable to be investigated systematically for aiding the development of efficient internal combustion system. An experimental study of flash boiling spray combustion in a SIDI optical engine under early injection has been conducted. The fuel, Iso-octane, was used across all tests. Three fuel spray conditions experimented in the study: normal liquid, transitional flash boiling and flare flash boiling sprays, within each case that Pa/Ps ratio was set in (>1), (0.3~1), and (<0.3) respectively. A small quartz insert on the piston enables optical access for observing combustion process; non-intrusive measurements on flame radicals has been carried out using a high-speed color camera. With the use of digital image processing and color analysis, the imaging system was turned into an abstract multi-spectral system to determine the characteristics of flame emission. In addition, the near infrared region was capable of being discriminated from the rest regions of the flame using HSV color model. The near infrared flame area and diffusion flame region as well as pool fire were found to be reduced, when implementing flash boiling spray under early injection condition. It is found that flash boiling spray contributes the reduction of particulate number (PN) emissions in exhaust gas and makes the improvement of indicated mean effective pressure (IMEP) and cyclic variation, which lead to more efficient combustion in SIDI engine under early injection.
Sun, Zhe, Ma, Zhen, Li, Xuesong, Xu, Min
Experimental Investigations on the Performance and Cold Starting Characteristics of a Low Compression Ratio Diesel Engine2019-01-05584/2/2019
In this experimental work, the potential advantages of lowering the Compression Ratio (CR) of a diesel engine in terms of performance, combustion and emission related parameters along with the analysis and improvement in its cold starting characteristics are presented. The CR of a single cylinder direct injection common rail diesel engine used for light-duty automotive applications was lowered from 18:1 to 14:1 by suitable modifications to the combustion bowl while retaining its shape. The engine with both the CRs was tested on a dynamometer rig under similar operating and fuelling conditions. Additionally, experiments were carried out to determine the extent to which in-cylinder smoke emissions can be reduced when the Nitric Oxide (NO) levels of 14 CR are matched to the higher levels seen in 18CR. In order to evaluate cold start ability and idling stability of the engine with a reduced CR (14:1), the engine was instrumented inside a cold chamber. The engine was soaked at different low temperatures ranging from 25 °C to -7 °C and experiments were performed to determine its cold start ability. The effects of injection scheduling and injection quantity on cold start ability are determined with the help of an open engine controller. Further, the improvement on start ability with the help of a grid heater was also evaluated.
Mithun, S, Ramesh, A
SAE Architecture Analysis and Design Language (AADL) Annex Volume 2:Annex B: Data Modeling AnnexAnnex D: Behavior Model AnnexAnnex F: ARINC653 AnnexAS5506/2 (Current)2/18/2019
AS-2C Architecture Analysis and Design Language
Development of a Climate and Altitude Simulation Test Bench for Handheld Power Tools2018-32-003310/30/2018
A climate and altitude conditioning test bench was developed at the Institute of Energy Efficient Mobility (IEEM) of Karlsruhe University of Applied Sciences to evaluate the overall sustainability of using innovative biofuels in handheld power tools such as chainsaws, trimmers and blowers under any typical operating condition worldwide. The 6 m3 hermetically sealed and thermally insulated test chamber is large enough to fit the entire power tool. A two-stage refrigeration system with intake air drying and electric heating allows for realistic temperature conditions to be set in the test chamber, ranging from arctic cold to tropical heat (-28 to 45 °C). Altitudes of up to 3500 m above sea level can be simulated using a throttle valve at the inlet of the chamber and a pressure-controlled rotary screw compressor positioned downstream the test chamber outlet. The air-cooled engines to be tested are fully exposed to the ambient conditions inside the test chamber, are able to aspirate the conditioned combustion air freely and release both exhaust gas and waste heat into the chamber environment. In order to control the power tool’s operation when the chamber is closed, an adaptive remote control system was specially developed. It enables automatic engine start-up by cable pull (e.g. for cold start testing), engaging the choke valve as well as operating the throttle lever automatically. This paper discusses the development process, the design, the operating limits of the climate and altitude simulation test bench as well as first tests on the reproducibility of the automatic start procedure, particularly important for future cold start investigations.
Martel, Artur, Scholl, Fino, Weierter, Dennis, Kettner, Maurice
Development of a Simulation Tool for High Capacity Metal Foam Heat Exchanger with Phase Change Material2018-01-07834/3/2018
Metal foam with their high porosity and heat storage capacity can be combined with phase change materials to be a powerful heat storage device. Numerical simulations of metal foam behavior can be challenging due to their complex geometric patterns necessitating high mesh requirements. Furthermore, simulations of the inner workings of a metal foam heat exchanger comprising of a large number of individual metal foam canisters can be impossible. The objective of the current work is to develop a computational model using a proprietary CFD tool Simerics-MP/Simerics-MP+® to simulate the workings of a metal foam heat exchanger with phase change element. A heat transfer coefficient capturing this heat transfer between wax and metal is used to formulate the “simplified” mixture model. The versatility of the proposed model is in the universality of its application to any shape or structure of metal foam. The computational model developed is tested to replicate the results of the 3D simulation. Very good agreements for the coolant temperature rise between the model and 3D simulation are obtained. Metal foam heat exchangers comprising of 89 such individual single metal foam canisters are simulated using the “simplified” model. Different arrangements of the single metal foam canisters to make up the metal foam heat exchanger are explored. Simulation results show pure steel has a better heat transfer performance, followed by metal foam canister with phase change material and finally aluminum. However, weight and other material considerations can make the metal foam canisters a practical alternative for effective heat storage.
Srinivasan, Chiranth, Slike, Jody, Wang, De Ming, Gao, Haiyang
Development of a Cold Start Fuel Penalty Metric for Evaluating the Impact of Fuel Composition Changes on SI Engine Emissions Control2018-01-12644/3/2018
The U.S. Department of Energy’s Co-Optimization of Fuels and Engines initiative (Co-Optima) aims to simultaneously transform both transportation fuels and engines to maximize performance and energy efficiency. Researchers from across the DOE national laboratories are working within Co-Optima to develop merit functions for evaluating the impact of fuel formulations on the performance of advanced engines. The merit functions relate overall engine efficiency to specific measurable fuel properties and will serve as key tools in the fuel/engine co-optimization process. This work focused on developing a term for the Co-Optima light-duty boosted spark ignition (SI) engine merit function that captures the effects of fuel composition on emissions control system performance. For stoichiometric light-duty SI engines, the majority of NOx, NMOG, and CO emissions occur during cold start, before the three-way catalyst (TWC) has reached its “light-off” temperature. This light-off temperature depends on the exhaust composition, which changes with fuel formulation. Thus, the time to achieve light-off, and therefore the cold start emissions, depends on fuel composition. Since the time to reach light-off must be minimized to meet emissions regulations, modern vehicles employ cold start strategies that intentionally release fuel energy into the engine exhaust to heat the TWC above the light-off temperature as quickly as possible. The fuel penalty associated with catalyst heating during cold start provides a link between fuel properties, emissions performance, and engine efficiency. This paper describes the derivation of the Co-Optima SI engine merit function term for emissions control, which is based on the cold start fuel penalty for catalyst heating and the catalytic light-off temperature for a particular fuel composition. It also discusses the process used for extracting cold start fuel penalties from chassis dynamometer data sets previously collected at ORNL. The form of the merit function term is simple, but it is only intended as a starting point for comparing the potential impacts of changes in fuel formulation on emissions control system performance.
Pihl, Josh, Thomas, John, Sinha Majumdar, Sreshtha, Huff, Shean, West, Brian, Toops, Todd
Kohler engineers new 5400 engines for lower NVH, easier start-ups17TOFHP12_1012/1/2017
For lawn tractor applications, easy-starting and smooth-operating engines are key to user satisfaction. Wisconsin-based engine and power systems manufacturer Kohler has announced an all-new 5400 Series engine line purpose-built to address these mower ergonomic attributes. The single-cylinder, OHV engine line includes models from 17 to 19.5 hp (12.7 to 14.5 kW) and includes brand-new features for the riding lawn-equipment market. “When it comes to lawn tractors, users want an engine that's easy to start, smooth running, simple to maintain and built to last. Our new 5400 Series more than delivers by incorporating a variety of user-friendly advancements,” said Brett Wegner, product manager for Kohler Engines. “When developing this line, we applied our expertise from Kohler's robust twin-cylinder engines to design in many durable features and user benefits. Without question, the 5400 Series takes our single-cylinder offering for ride-on mowers to the next level.”
Borst, Matthew
Trends in Hydraulic FiltrationTBMG-2794212/1/2017
Proper filtration plays an important role in ensuring that hydraulic systems operate trouble-free. High-performance filters maintain the cleanliness of the hydraulic fluid over its entire service life. In addition, designers are faced with ever-changing application requirements — longer filter change intervals, higher operating safety, increased separation efficiencies, and increased compatibility with the new generation of hydraulic oils. Following is an overview of some important technologies and trends in the industry, and their impact on users of hydraulic systems.
Heating Ethanol, the 3 rd Generation2017-36-024711/7/2017
The first generation of heated cold start systems for flex fuel vehicles in Brazil were launched in 2009 and have solved most of the issues around the former gasoline sub-tank concept. This new technological approach focused on concerns like the user experience by having the need to fulfill the sub-tank, on complains related to possible old gasoline left inside, in the complexity of the electro mechanic nozzles and other possible improvements. Some years later, the second generation expanded the initial cold start application to a mature drivability enhancement and further possibility of usage as a support for emission reduction. A leaner electronic control and heat sink concept also represented an alternative to the first generation, and an engineered plastic fuel rail replaced the first metallic concept, which was an option to the initial concerns about the combination of high temperatures and fuel. This paper will show the evolution of the previous generations of heating systems for ethanol, presenting the engineering advance that resulted in a new heating concept, strategy simplification, new components and the possibility of system usage to perform functionalities that were not foreseeing on its first ideation. Further laboratory and vehicle experiments will demonstrate the theory and simulation behind the 3rd generation concept.
de Oliveira Junior, Fernando, Gentini, Isaac, Lepsch, Fernando, Siegle, Alex, Ferreira, Guilherme Torres
Impact of Ambient Temperature Conditions on Cold Start Combustion, Gaseous and Particle Emissions from Gasoline Engines2017-01-228610/8/2017
Ambient temperature conditions, engine design, fuel, lubricant and fuel injection strategies influence the cold start performance of gasoline engines. Despite the cold start period is only a very small portion in the legislative emission driving cycle, but it accounts for a major portion of the overall driving cycle emissions. The start ability tests were carried out in the weather controlled transient dynamometer - engine test cell at different ambient conditions for investigating the cold start behavior of a modern generation multi-point fuel injection system spark ignition engine. The combustion data were analyzed for the first 200 cycles and the engine performance and emissions were analyzed for 300 s from key-on. It is observed that cumulative fuel consumption of the engine during the first 60 s of engine cold starting at 10 °C was 60% higher than at 25 °C and resulted in 8% increase in the value of peak speed of the engine. The rate of pressure rise was significantly higher and prolonged for a number of cycles at 10°C compared to 25 °C and 45 °C. The cycle-to-cycle variation in the cylinder pressure at 10 °C was three times higher than at 25 °C. The first 60 sec of the cold start cumulative CO emission at 10 °C was approximately 3 times higher; cumulative HC emission was 3.5 times higher; cumulative NOx emission was 50% lower than that of at 25 °C. The particles in the size range of 50-200 nm are accounted for 60% at 10 °C and 6-8% at 25 °C & 45 °C ambient temperature conditions. The exhaust particles at the low ambient temperatures increased the exhaust particulate mass by 30 times at 10 °C in comparison with that of at 25 °C. The accumulated unburned fuel during the cold start period combusted abruptly and caused for the higher peak speed and exhaust emissions.
Ramadhas, A S, Singh, Punit Kumar, Mathai, Reji, Sehgal, Ajay Kumar
Numerical Models for PEMFC Cold Start: A Review2017-01-11823/28/2017
Startup from subzero temperature is one of the major challenges for polymer electrolyte membrane fuel cell (PEMFC) to realize commercialization. Below the freezing point (0°C), water will freeze easily, which blocks the reactant gases into the reaction sites, thus leading to the start failure and material degradation. Therefore, for PEMFC in vehicle application, finding suitable ways to reach successful startup from subfreezing environment is a prerequisite. As it’s difficult and complex for experimental studies to measure the internal quantities, mathematical models are the effective ways to study the detailed transport process and physical phenomenon, which make it possible to achieve detailed prediction of the inner life of the cell. However, review papers only on cold start numerical models are not available. In this study, an extensive review on cold start models is summarized featuring the states and phase changes of water, heat and mass transfer. To begin with, the states of water in PEMFC are discussed. Then, the distinct stages for cold start process are introduced. Last but not least, various numerical models are reviewed by dividing into four categories: zero, one, two, and three dimensional models. In particular, the sets of governing equations of three dimensional models are presented in detail. Finally, the cold start strategies from the aspects of material/structure and cold start process are recommended, and the four strategies: material/structure optimization, gas purging, thermal insulation, and heating, are reviewed in detail. For conclusion, it is suggested that a proper numerical model of PEMFC which features internal physical phenomenon inside cell comprehensively is a strong tool to investigate cold start process and provide much information for successful startup. Besides, reasonable cold start strategies should be established to demonstrate successful startup from subzero temperature.
Guo, Xin, Peng, Xu, Xu, Sichuan
Experimental Investigation of Fuel Film Characteristics of Ethanol Impinging Spray at Ultra-Low Temperature2017-01-08513/28/2017
Increasing the injection pressure in DISI engine is an efficient way to obtain finer droplets but it will also potentially cause spray impingement on the cylinder wall and piston. Consequently, the fuel film sticking on the wall can dramatically increase the soot emission of the engine especially in a cold start condition. On the other hand, ethanol is widely used as an alternative fuel in DI engine due to its sustainable nature and high octane number. In this study, the fuel film characteristics of single-plume ethanol impinging spray was investigated. The experiments were performed under ultra-low fuel/plate temperature to simulate the cold start condition in cold areas. A low temperature thermostatic bath combined with specially designed heat exchangers were used to achieve ultra-low temperature for both the impinging plate and the fuel. Laser induced fluorescence (LIF) technique was employed to measure the thickness of fuel film deposited on the impinging plate. Rhodamine 6G was resolved into ethanol as the tracer, which can be excited by 532 nm laser and fluorescence at 560-590 nm. A low speed imaging system was used to capture the film characteristics. The LIF signal was converted to film thickness following a known height calibration approach. It was found that, with the decrease of plate temperature, the average film became thicker and the adhered mass increased although the wetted area became smaller due to the larger viscosity. Moreover, lower fuel temperature leads to thicker film and more adhered mass. The wetted areas are close to each other under different fuel temperatures.
Pan, Hujie, Xu, Min, Hung, David, Lv, Huijia, Dong, Xue, Kuo, Tang-Wei, Grover, Ronald O., Parrish, Scott E.
Effects of Port Injection Specifications on Emission Behavior of THC2016-32-006511/8/2016
In port injection, it is difficult to control in-cylinder fuel supply of each cycle in a transient state as cold start (in this paper, cold start is defined as several cycles from cranking at low engine temperature). Hence, THC, which is one of regulated emission gases, is likely to increase at cold start. As one of THC emission reduction approaches at cold start, the optimization of fuel injection specifications (including injection position and spray diameter) is expected to reduce THC emission. Setting injection position as downstream position is expected to secure the in-cylinder fuel supply amount at cold start because of small fuel adhesion amount on an intake port wall and a short distance between the injection position and in-cylinder. The position injection contributes to reduction of THC emission due to elimination of misfire. Additionally, fuel atomization is also expected to effective at cold start because mixing promotion caused by fuel atomization is dominant in low engine temperature. On the other hand, the effect of injection specifications under warm-up (in this paper, the engine temperature is relatively lower than hot condition) is also evaluated in this paper. Additionally, the spray behavior in intake port is observed by visualization in intake port. In this paper, fuel atomization method is injection pressure increasing. In comparison with the upstream position injection, downstream position injection improves engine startability and reduces THC emission. Furthermore, the spray diameter at cold start decreases with increases in injection pressure. On the other hand, the fuel adhesion amount on intake valve surface under warm-up becomes less than that at cold start. The THC emission remains approximately the same, regardless of fuel atomization.
Nakao, Yoshinori, Sakurai, Yota, Hisano, Atsushi, Saitou, Masahito, Kazari, Masahide, Murase, Takahito, Suzuki, Kozo
Development of Ultra-Low Synergized PGM as Diesel Oxidation Catalyst for Heavy-Duty Applications2016-01-232110/17/2016
Stricter regulatory standards are continuously adopted worldwide to control heavy duty emissions, and at the same time, fuel economy requirements have significantly lowered exhaust temperatures. The net result is a significant increase in Precious Group Metal (PGM) usage with current Diesel Oxidation Catalyst (DOC) technology. Therefore, the design and development of synergized precious metal (SPGM) in which ultra-low PGM is synergized with mixed metal oxide (MMO) to achieve highly beneficial emission performance improvement, is necessary. The presence of MMO in SPGM is responsible for NO oxidation to NO2 which is critical for the passive regeneration of the downstream filter and SCR function. This paper presents an initial study outlining the development of MMOs for application in modern DOCs and addresses some specific challenges underlying this application. Lab and flow reactor data in this study demonstrated SPGM DOCs thermal resistance and sulfur poisoning resistance. In addition, SPGM DOC with reduced PGM levels indicated the increase of NO2 production at T>250 °C compared to OEM benchmarks. This paper outlines the results of engine dyno, transient dyno and on-road testing of SPGM DOCs versus OEM DOCs. The engine testing indicated high level of NO2 production at significantly reduced PGM levels. On-road testing showed no change or deterioration of the system performance after the switch to SPGM for a heavy duty DOC and filter system. Field data logging during on-road testing showed identical exotherms for the same active regeneration calibration, which results in equivalent DPF regeneration. Disclosed SPGM for on-road heavy-duty applications is consistent with sufficient CO and HC conversion and superior warmed up NO2 make. Specific challenges remain in the development of the SPGM DOC which is under investigation based on formulation and mechanism of mixed metal oxides.
Nazarpoor, Zahra, Golden, Steve, Launois, Maxime, Kitazumi, Sen, Xie, Dianyong, McConnell, Campbell
GDi Cold Start Emission Reduction with Heated Fuel2016-01-08254/5/2016
LEV-3 regulation changes require 100% SULEV30 fleet average by 2025. While present applications meeting SULEV30 are predominately small displacement 4-cylinder engines, LEV-3 standards will require larger displacement engines to also meet SULEV30. One concept previously investigated to reduce the cold start engine-out HC emissions was to heat the fuel injected during the cold start and initial engine idle period. Improved atomization and increased vaporization of heated fuel decreased wall wetting and unburned fuel. This resulted in more fuel available to take part in combustion, thus reducing the required injected fuel mass and HC emissions. Single cylinder engine testing with experimental heated Gasoline Direct Injection (GDi) injectors was conducted at 40°C engine coolant and oil temperature conditions. The operating mode simulated cold start idle operating conditions, with split injection for improved Catalyst Light-Off (CATLO) times. Testing showed that fuel heating increased engine stability at leaner Air/Fuel (A/F) ratios. The leaner A/F ratio operation reduced emissions, particulates and smoke. These results led to further investigations in a vehicle platform. The method of heating the fuel was altered due to hardware limitations, and pre-heating a fuel rail and GDi injector fuel coils were used to produce a representative fuel stream temperature profile, previously measured with experimental Heated GDi injectors. Heated versus unheated gasoline cold start emission performance was compared on a 3.8L 6-cylinder naturally aspirated vehicle which demonstrated a reduction in HC emissions using heated fuel. The experimental GDi injectors, single cylinder test results, fuel heating methodology, vehicle installation, engine re-calibration, as well as comparisons of engine-out and tailpipe emissions produced with unheated and heated fuel are presented and discussed.
Fedor, William, Kazour, Joseph, Haller, James, Dauer, Kenneth, Kabasin, Daniel
Evaluation of Cold Start Technologies on a 3L Diesel Engine2016-01-08234/5/2016
Increasingly stringent emissions regulations require that modern diesel aftertreatment systems must warm up and begin controlling emissions shortly after startup. While several new aftertreatment technologies have been introduced that focus on lowering the aftertreatment activation temperature, the engine system still needs to provide thermal energy to the exhaust for cold start. A study was conducted to evaluate several engine technologies that focus on improving the thermal energy that the engine system provides to the aftertreatment system while minimizing the impact on fuel economy and emissions. Studies were conducted on a modern common rail 3L diesel engine with a custom dual loop EGR system. The engine was calibrated for low engine-out NOx using various combustion strategies depending on the speed/load operating condition. The technologies that showed strong potential during this evaluation include a turbine bypass system, early exhaust valve opening, cylinder deactivation, and delayed engine starting. The performance of these technologies was compared using an engine test cell which was programmed to simulate the first portion of the FTP-75 test cycle.
Miwa, Jason, Mehta, Darius, Koci, Chad
Metric-based Evaluation of Software Architecture for an Engine Management System2016-01-00374/5/2016
Powertrain software development for series production faces multifaceted challenges related to high functional complexity, high quality standards, reduced time to market and high development costs. Software architecture tackles the above mentioned challenges by breaking down the complexity of application software into modular components. Hence, design errors introduced during that phase cause significant cost and time deviations. Early and repeated analysis of new and modified architecture artifacts is required to detect design errors and the impact of the subsequent changes in the software architecture. Engine management software has a high degree of functional complexity and large number of system variants depending upon market requirements. This paper deals with the methods to perform automated evaluation of Renault’s EMS 2012 Engine Management Software in a Continuous Integration Framework. The adopted approach enables frontloading of development effort, avoids quality risks at a later stage of development and reduces time and cost for series software development.
Venkitachalam, Hariharan, von Wissel, Dirk, Richenhagen, Johannes
Development of a Rear Powertrain Cooling System for a Minivan2016-01-06544/5/2016
The paper presents the development of a proposed rear powertrain cooling system of a minivan. The packaging of cooling system is finalized such that the radiator faces towards the rear of the vehicle bumper which is opposite to the conventional rear cooling system (i.e. radiator faces towards the front of the vehicle). In the small minivan, the space ahead of the engine is used as a floor for passenger foot. Due to these space constraints, the cooling system has no choice, but to move rear of the vehicle and above the departure plane to meet packaging requirements. Furthermore, in the conventional rear cooling system, in front of the radiator, there is engine and exhaust system, which heats up the air going to the radiator and reduces radiator cooling performance. Thus the cooling system is placed such that the radiator faces the rear bumper to draw in cooler air. In this condition we don’t depend on the ram air but on the fan to meet required airflow. 1D simulation using LMS-Amesim and CFD tools FLUENT are used for conceptual study. Comparison study on air flow, cooling performance and under-hood temperature is done by testing on a mule vehicle. Grill opening, departure angle, critical components heights and surrounding body panels for underbody are considered in packaging of the vehicle. The air flow, ROA of Coolant and ROA of Oil are measured for two conditions, i.e. radiator facing towards rear bumper and radiator facing towards powertrain. It is observed that the effect of rear vortex has negligible impact on the airflow provided by the fan, for vehicle speed less than 65kmph.
Brahmasani, Lakshmaiah, K, Sarangapani, Solomon, Samson, Khan, Parvej
Influence of Coolant Temperature on Cold Start Performance of Diesel Passenger Car in Cold Environment2016-28-01422/1/2016
Diesel engines are the versatile power source and is widely used in passenger car and commercial vehicle applications. Environmental temperature conditions, fuel quality, fuel injection strategies and lubricant have influence on cold start performance of the diesel engines. Strategies to overcome the cold start problem at very low ambient temperature include preheating of intake air, coolant, cylinder block. The present research work investigates the effect of coolant temperatures on passenger car diesel engine’s performance and exhaust emission characteristics during the cold start at cold ambient temperature conditions. The engine is soaked in the -7°C environment for 6 hours. The engine coolant is preheated to the desired coolant temperatures of 10 and 20°C by an external heater and the start ability tests were performed. The coolant temperature of 10°C in the -7 °C environment improved the fuel combustion and thereby reduced the cranking period by half; reduced the peak HC emissions and NOx emissions by 85% and 30% respectively. The cold ambient conditions increased the accumulation mode particles by 60% and decreased the nucleation particles by 70% compared to that of normal ambient temperature (+20°C). The coolant temperature of 10°C decreased the accumulation particles by ∼ 30% compared to normal ambient temperature. The number count of larger particulates of size 100-1000 nm doubled whereas particulates of diameter less than 100 nm reduced by 20% at -7°C environment compared to +20°C. Coolant temperature of 20°C in the low ambient temperature conditions decreased the total particulate mass to 1/7th of that at cold ambient conditions. The coolant heating strategy improved the cold start performance of the engine at cold ambient temperature conditions and thereby would reduce the overall driving cycle emissions as well.
Ramadhas, A S, Xu, Hongming
Patented Software Solution to Prevent Rotation of the Tool Upon Machine Start at Idle2015-32-084311/17/2015
During the start-up phase of machines it can happen that tools are inadvertently rotating, which is caused by the half-throttle setting. Due to the starting throttle locking mechanism, the engine's rotational speed is above the engagement speed of the tool (for example the chain of a chain saw). This article describes the software algorithms developed by PRUFREX that are able to prevent rotation of the tool upon machine start at idle. The patented software solution is able to differentiate between start behavior with and without a starting throttle locking mechanism based on the machine's speed and time information and, as a result, can identify or estimate the position of the throttle valve. The effect of the algorithms is the switch-over between different ignition curves that are stored in the microcontroller-operated ignition modules. This includes a provision in the start ignition curve that prevents the tool from rotating. Toggling between different ignition curves is already part of today's technology. The underlying patent defines the conditions for switch-over that is solely controlled by software. The article explains the various machine states and their identification in detail. The possible program sequence is featured.
Lajda, Marek, Hook, Sebastian, Reimgen, Nikolai
Start Energy Efficiency on Flex Fuel Engines2015-36-03359/22/2015
The new Brazilian program Inovar Auto coming in 2017 has raised the level of efficiency awareness from vehicle fuel economy in km/L to energy consumption in MJ/km. In this scenario, automakers are implementing several vehicle optimization strategies and new technologies to meet vehicle energy efficiency targets and consequently reduce fuel consumption and exhaust gases emissions. One of these technologies is the START-STOP system that basically turns the engine off when the vehicle is at idle and after some safety and operating trigger conditions are met. A new concept has been developed to evaluate an internal combustion engine start efficiency considering both the electric energy provided by starter motor and the fuel chemical energy required to start and sustain combustion. This concept of start efficiency is of particular interest for Flex Fuel engine where there is a high difference in energy content level between commercial gasohol (E27) and hydrous ethanol (E100) fuels. The method showed to be adequate to parameterize engine start events in addition to conventional parameters like starting time, quality and flare. Furthermore, it has been possible to compare total energy required for starting against idle energy consumption. This paper presents the engine starting efficiency concept and the results of a 1.0L Flex Fuel engine tested with E27 and E100. The effect of start efficiency parameter in function of coolant temperature is also investigated for both fuels.
Algate, Victor Hugo S., Engler Pinto, Claudio M.
Warm Start Robustness Improvement Using the Heated Cold Start System in Flex Fuel Engines2015-36-02029/22/2015
This paper presents a new ethanol content identification concept, with focus on flex fuel vehicles start ability robustness. The solution refers to the usage of cold start system based on heated fuel rail (normally used for low temperatures) in a preventive way like an ethanol sensor, ensuring a successful start attempt in specific conditions, even at high ambient temperatures. At most of flex fuel projects, the ethanol content calculation (or the percentage of ethanol in fuel) is done through the oxygen sensor (also called lambda sensor). Therefore the engine start strategy considers the fuel mixture determined in the previous vehicle operation. In situations when the adaptation cycle is not completed during the operation cycle previous to the start attempt, and also in combination with an extreme fuel exchange situation after tanking (previous to the last vehicle operation cycle), it may happens that the first start attempt is not successful. In this case the engine management strategy acts reactively to ensure a proper engine start and drivability until the correct ethanol content is calculated. The new concept heats the fuel in these specific conditions, using this additional fuel line ethanol content information to adjust the mixture parameters, ensuring the start ability. Thus, the engine management is not anymore reactive and can preventively act before the engine start, improving the flex fuel system robustness without the need of additional components.
de Oliveira, Fernando, Lepsch, Fernando, Silva, Leandro Luiz Franco da, de Brito Oliveira, Luiz Fernando, Coletto, Tulio Italico Moreira
Measurements of Time-Resolved Mass Injection Rates for a Multi-Hole and an Outward Opening Piezo GDI Injector2015-01-09294/14/2015
Time-resolved mass injection rates of an outward opening piezo-actuated and a solenoid actuated multi-hole GDI injector were measured to investigate (1) the influence of both hardware and software settings and (2) the influence on the injection rates from a wide range of operational parameters and (3) discuss limitations and issues with this measurement technique. The varied operating parameters were fuel pressure, back-pressure, electrical pulse width, single/double injection and injection frequency. The varied hardware/software parameters were injector protrusion, upstream fuel pressure condition and the cut-off frequency of the software's low-pass filter. Signal quality was found to be dependent on both hardware and software settings, especially the cut-off frequency of the low-pass filter. Measurements with high signal quality were not possible for back-pressures lower than 0.5 MPa. For the smallest possible injections, the piezo-actuated injector was found to be superior since it can inject very small amounts of fuel very accurately with little fuel pressure dependency. For engine realistic back-pressures, the multi-hole injector was found to be back-pressure independent. The piezo injector however was found to be strongly influenced by the back-pressure. The dynamic range was found to be much higher for the piezo injector, and the non-linear flow area was much larger for the multi-hole injector. Both injectors were capable of double injections but the piezo can use shorter dwell times. Effects of upstream fuel pressure fluctuations, especially on the second injection of a double injection, must be carefully taken into account.
Dahlander, Petter, Iemmolo, Daniele, Tong, Yifei
Investigation on the Performance of Diesel Oxidation Catalyst during Cold Start at L ow Temperature Conditions2014-01-271210/13/2014
Cold start is a critical operating condition for diesel engines because of the pollutant emissions produced by the unstable combustion and non-performance of after-treatment at lower temperatures. In this research investigation, a light-duty turbocharged diesel engine equipped with a common rail injection system was tested on a transient engine testing bed to study the starting process in terms of engine performance and emissions. The engine (including engine coolant, engine oil and fuel) was soaked in a cold cell at −7°C for at least 8 hours before starting the test. The engine operating parameters such as engine speed, air/fuel ratio, and EGR rate were recorded during the tests. Pollutant emissions (Hydrocarbon (HC), NOx, and particles both in mode of nucleation and accumulation) were measured before and after the Diesel Oxidation Catalyst (DOC). The results show that conversion efficiency of NOx was higher during acceleration period at −7°C start than the case of 20°C start. The reduction of NOx and Total Hydrocarbons (THC) by the DOC was less during the idle period at −7°C cold start. Most of the nucleation particles were removed in both 20°C and −7°C conditions. Meanwhile, the accumulation particles were only reduced during the acceleration period at −7°C start due to the deposits caused by thermophoresis.
Liu, Dai, Xu, Hongming, Arumugam Sakunthalai, Ramadhas, Tian, Jianyi
Fuel Consumption and GHG Reductions by using Used Cooking Oil as a Fuel in a HGV under Real World Driving Conditions2014-01-272710/13/2014
Direct use of straight vegetable oil based biofuels in diesel engines without trans-esterification can deliver more carbon reductions compared to its counterpart biodiesel. However, the use of high blends of straight vegetable oils especially used cooking oil based fuels in diesel engines needs to ensure compatible fuel economy with PD (Petroleum Diesel) and satisfactory operational performance. There are two ways to use high blends of SVO (Straight Vegetable Oil) in diesel engines: fixed blending ratio feeding to the engine and variable blending ratio feeding to the engine. This paper employed the latter using an on-board blending system-Bioltec system, which is capable of heating the vegetable oils and feeding the engine with neat PD or different blends of vegetable oils depending on engine load and temperature. A used cooking oil derived SVO type of biofuel, the C2G Ultra Biofuel (C2G: Convert to Green), which is a fully renewable fuel made as a diesel replacement from processed used cooking oil, used directly in diesel engines specifically modified for this purpose, has been investigated in this research. A series of real world driving tests were conducted on a 44 ton articulated truck. A dual fuel tank containing both PD and the C2G Ultra Biofuel was installed. The engine was started with PD and then switched to C2G Ultra Biofuel gradually. The vehicle was tested on either neat PD or blended fuel mode with different load (empty or fully loaded trailer). The fuel consumption and tailpipe emissions were measured. This paper focused on the fuel consumption and GHG reductions. The fuel consumption was determined by volumetric, mass and energy per km travelled and per ton of GVW. The results show that the fuel consumption for neat PD and blends was at the similar level and has a good inverse linear correlation with GVW. The substitution ratio of PD by the C2G Ultra Biofuel is 86∼91% and 74∼81% for hot start and cold start trips respectively. The GHG reductions by the C2G Ultra Biofuel are 85∼89% and 73∼78% for hot start and cold start trips respectively.
Li, Hu, Campbell, Laura, Hadavi, Seyed, Gava, Job
Impacts of Cold-Start and Gasoline RON on Particulate Emission from Vehicles Powered by GDI and PFI Engines2014-01-283610/13/2014
An experimental study of particulate matter (PM) emission was conducted on four cars from Chinese market. Three cars were powered by gasoline direct injection (GDI) engines and one car was powered by a port fuel injection (PFI) engine. Particulate mass, number and size distribution were measured based on a chassis dynamometer over new European driving cycle (NEDC). The particulate emission behaviors during cold start and hot start NEDCs were compared to understand how the running conditions influence particulate emission. Three kinds of gasoline with RON 91.9, 94.0 and 97.4 were tested to find the impact of RON on particulate emission. Because of time and facilities constraints, only one cold/hot start NEDC was conducted for every vehicle fueled with every fuel. The test results showed that more particles were emitted during cold start condition (first 200s in NEDC). Compared with cold start NEDC, the particulate mass and number of hot start NEDC decreased by a wide margin. The particulate mass and number reductions of hot start NEDC mainly resulted from ECE cycle sections. The particulate mass and number of cold start ECE were much higher than that of the hot start ECE due to the inhomogeneous mixture combustion process during cold start condition. Gasoline RON had little impact on particulate emission emitted from the four test cars when their engines ran without knocking. However, when the GDI cars calibrated with a high RON gasoline ran with a low RON gasoline, the fierce knocking would occur under high load condition such as acceleration from 100km/h to 120km/h and increase the number of both nucleation and accumulation particles significantly.
Fu, Haichao, Wang, Yinhui, Li, Xinyan, Shuai, Shi-Jin
Impact of Cold Ambient Conditions on Cold Start and Idle Emissions from Diesel Engines2014-01-271510/13/2014
The cold start performance of a diesel engine has been receiving more attention as the European Commission emission regulations directed to include cold start emissions in the legislative emission driving cycles. The cold start performance of diesel engines is influenced by the ambient temperature conditions, engine design, fuel, lubricant and engine operating conditions. The present research work investigates the effect of cold ambient conditions on the diesel engine's performance and the exhaust emission (gaseous and particulate emissions) characteristics during the cold start and followed by idle. The engine startability and idling tests were carried out on the latest generation of diesel engine in a cold cell at various ambient temperatures ranging between +20°C and −20°C. Higher fuel consumption and peak speed were observed at very cold ambient compared to those at normal ambient during the cold start. The engine exhaust emissions were reached a peak value during the acceleration period of the cold start, and it decreased to maintain the idle speed. The exhaust emissions during the cold start and idle conditions were higher at very cold ambient conditions compared to normal ambient temperatures. The exhaust particle size distribution analysis indicated that the particle number concentration has been shifted towards larger diameter particles with a drop in ambient temperatures. The particulate mass at idle conditions was about 1/10th of that cold start for the all the temperature conditions. The relationship between the particle number and particulate mass during cold start and idle is also established. The cold start performance of the engine at very cold ambient conditions significantly affects the engine transient performance as well.
Arumugam Sakunthalai, Ramadhas, Xu, Hongming, Liu, Dai, Tian, Jianyi, Wyszynski, Miroslaw, Piaszyk, Jakub
Exhaust Emission Characteristics of Diesel Engine Using Jatropha Crude Oil Blends2014-01-277010/13/2014
Jatropha biofuel is promising renewal oil to produce biodiesel fuel through transesterification method which is shown in many papers. The ideal diesel alternative fuel obtained considering Jatropha as materials is Fatty Acid Methyl Ester (FAME). It is more desirable than the viewpoint of economical efficiency and CO2 control to operate a diesel engine with Jatropha crude (JC) oil. It is the purpose of this research to examine a possibility of using advantageous JC oil direct use as diesel engine fuel, in consideration of the sustainable production of the Jatropha biofuel in Mozambique. The adaptability to the diesel engine of diesel oil and the mixed fuel of JC was examined. Jatropha crude oil contains phorbol ester (PEs) which is a promoter of cancer. Measurement of the concentration of PEs in an exhaust gas was performed using High Performance Liquid Chromatography (HPLC). Skip cycle operation was performed for diesel engine with an electronically-controlled fuel injection system, and it was checked that the PEs concentration in the exhaust gas in low load operation which imitated cold starting condition. As a result of conducting the experiment by the JC mixed fuel up to JC60 had little influence on indicated thermal efficiency and the exhaust gas components except PM, and it has checked the possibility of utilization. However, PM in an exhaust gas increased in proportion to the mixed ratio of JC. Also in the skip cycle which imitated cold starting, it checked that the PEs concentration in an exhaust gas was below a detection limit.
Kato, Satoshi, Kobashi, Yoshimitsu, Suzuki, Yasumitsu, Tosa, Koji, Asaka, Katsuyoshi, Macamo, Alberto
Self-Controlled Electronic Cold Start System for Flexible Fuel Vehicles2014-36-02089/30/2014
Flexible fuel vehicles have been a challenge for the automotive industry due to the chemical properties of ethanol combustion. Especially on days in which the ambient temperature is below 18 degree Celsius, flexible fuel starting is critical due to high ethanol flash point. To solve this problem, cold start systems have been implemented in flexible fuel vehicles. Cold start systems that inject gasoline to assist in starting have been widely used. However, they dramatically increase the level of pollutant emissions during the cold start phase and they depend on the driver interactivity to refill the system with gasoline. Cold start systems using electric pre-heating have been recently launched into the automotive industry. However, these systems rely on a dedicated electronic monitoring unit for temperature corrections in real time and protection against overheating, increasing the hardware and vehicle calibration complexity and thus demanding high costs for implementing this technology. This paper presents the concept of the new electronic cold start technology self-controlled by semiconductor, what allows the elimination of additional electronic controls. The technology operation principle and high performance in cold starting achieved are studied and presented through laboratory tests.
Amaral, Tadeu Miguel Malagó, Moreira, Fábio, Yoshino, Fernando Jun, Cavalhieri, Heitor Moreira, da Cruz, Roberta Jussara Silva Diniz, Schadler, Werner
A Comparison of Cold-Start Behavior and its Impact on Fuel Economy for Advanced Technology Vehicles2014-01-13754/1/2014
Vehicle operation during cold-start powertrain conditions can have a significant impact on drivability, fuel economy and tailpipe emissions in modern passenger vehicles. As efforts continue to maximize fuel economy in passenger vehicles, considerable engineering resources are being spent in order to reduce the consumption penalties incurred shortly after engine start and during powertrain warmup while maintaining suitably low levels of tailpipe emissions. Engine downsizing, advanced transmissions and hybrid-electric architecture can each have an appreciable effect on cold-start strategy and its impact on fuel economy. This work seeks to explore the cold-start strategy of several passenger vehicles with different powertrain architectures and to understand the resulting fuel economy impact relative to warm powertrain operation. To this end, four vehicles were chosen with different powertrain architectures. These include a modern conventional vehicle with a 6-speed automatic transmission equipped with a torque converter, a downsized and turbocharged GDI vehicle with a 7-speed dual-clutch transmission, a modern turbo-diesel with a 6-speed dual-clutch transmission, and a gasoline-electric hybrid with a power split transmission. The vehicles were operated on a chassis dynamometer with instrumentation in place to determine real-time fuel consumption and tailpipe emissions while observing powertrain behavior. The test vehicles were subjected to hot and cold start iterations of the EPA Urban Dynamometer Driving Schedule (UDDS) and US06 drive cycles at 72°F ambient test cell temperature. The vehicles were found to exhibit increased fueling rates, mild changes in shifting behavior, larger levels of tailpipe emissions, and changes to secondary operating strategies such as deceleration fuel cutoff. The duration of cold start behavior varied between the vehicles, and was directly affected by the aggressiveness of the drive cycle. The severity of the cold start penalty was found to vary with vehicle architecture and drive cycle, but was generally smaller for more aggressive vehicle operation. Cold start penalties ranged from a low of 10.5% on the US06 drive cycle to a maximum of 21.8% on the UDDS cycle.
Anderson, Jay, Rask, Eric, Lohse-Busch, Henning, Miers, Scott
Experimental Investigation of Six Cylinder Turbocharged Di-Diesel Engine Cold Startability2014-01-13724/1/2014
Modern day ECU controlled Compression Ignition Engine, with its lean burn combustion process and with advanced exhaust aftertreatment devices, is the most sought after IC engine today; Due to its low fuel consumption with lowest possible CO2 emissions. In order to meet these low emission targets, the compression ratio of many of these new generation Diesel engines are kept as low as low as 16:1. Lowering compression ratio has a negative effect on Engine cold start quality and warm-up. This paper summarizes experimental investigation conducted on an Inline 6 cylinder 5.7 liter Turbocharged Intercooled Direct Injection Diesel Engine with BOSCH Electronic Rotary Fuel Injection Pump (VP37) in a cold chamber to study the effect of injection parameters on combustion instability (and thereby on Cold Cranking), at different (sub-zero) ambient temperatures. Acceptance criterion for cold cranking of Engine was it should start and stabilize within 30sec of the cranking time without visible white smoke emission. Focus of this exercise was to simulate worst case condition and optimize the calibration of FIE (Fuel Injection Equipment) system to facilitate engine cold cranking without cold start aid (Glow Plugs, Intake Air Heaters, Coolant Heaters, and Fuel Heater).
B, Dinesh Kumar, Murugesan, Leelakumar, Nagarajan, M, Kakde, Nitin, Mahesh, P
Ethanol Flex Fuel system with Delphi Heated injector application2014-01-13694/1/2014
After the second worldwide oil crisis, Brazil put in place by 1975 a strategic plan to stimulate the usage of ethanol (from sugar cane), to be mixed to the gasoline or to be sold as 100% ethanol fuel (known as E100). To enable an engine to operate with both gasoline and ethanol (and their mixtures), by 2003 the “Flex Fuel” technology was implemented. By 2012 calendar year, from a total of about 3.8 million vehicles sold in the Brazilian market, 91% offered the “Flex Fuel” technology, and great majority used a gasoline sub-tank to assist on cold starts (typically below 15°C, where more than 85% of ethanol is present in fuel tank). The gasoline sub-tank system suffers from issues such as gasoline deterioration, crash-worthiness and user inconvenience such as bad drivability during engine warm up phase. This paper presents fuel injector technologies capable of rapidly electrically heating the ethanol fuel for the Brazilian transportation market. These heated fuel injectors can be used for cold starting ethanol fueled engines as presented in SAE paper 2009-01-0615 [1] and to enable emissions reduction with a variety of automotive fuels as presented in SAE paper 2010-01-1265 [2]. This paper will demonstrate the benefits and advantages obtained by introducing the individually-controlled heated injectors on Hyundai HB20 1.6L Flex Fuel vehicles, which besides assisting on cold starts, also helps to meet upcoming emissions legal requirements (Proconve L6). Additionally, it will enable meeting future stringent regulations that will require unburned ethanol (ETOH) emission to be considered by Brazilian legislation. Through significant fuel injection optimization on both cold start and emissions, these advantages will also allow lowering fuel consumption with E100 and potential catalyst converter savings.
Krenus, Roberto, Passos, Marcos R. V., Ortega, Thiago, Mowery, Kenneth, Kim, Young Jin, Lavan, Lucille G., Lee, Kuho, Park, C.J., Han, Kwang
Evaluation of Value Proposition and Interactive Features for Motorcycles with Electronic Fuel Injection for Indian Market2013-32-912210/15/2013
Growth and mobility expectation in India has increased competition in the Indian two wheeler industry. Value proposition targeting improved performance, fuel economy, user-friendly features are being seen as key differentiators. The expected introduction of EFI (Electronic Fuel Injection) leads to additional system cost which needs to be justified from tangible end-customer benefits. The previous SAE papers [1] [2] attempted to provide an insight into the carbureted engine vs. fuel injection systems from fuel efficiency, combustion quality perspective and also enumerated the benefit of fuel economy to end user. To increase the benefit to the end customers, the authors propose to provide insight into innovative system concepts with interactive features. The evaluation targets the commuter segment where the implementation and acceptance potential is high. The results thus derived on the motorcycle under consideration are promising and has high potential to meet the needs of the end user. Throttle enabled start, start-stop, bypass less throttle body, operating mode selection, “battery dead” ignition are a few of the features which can be implemented for a EFI bike increasing the value proposition and reducing the overall system cost for the OEM.
R, Pradeep, Shetty, Ajay, M, Prabhu Panduranga
A New Measurement Technique for Online Oil Dilution Measurement2013-01-252110/14/2013
New trends in the development of combustion engines lead to changed engine operating conditions which also result in changed loads of the engine parts and functional components. The application of regenerative fuels and new exhaust after- treatment systems can for example lead to an increased input of fuel into the engine oil. Oil dilution is an issue that impacts the engine operation and life cycle and therefore gains importance during the development process of combustion engines. In order to improve oil dilution to preclude destructive amounts of fuel in the oil it is necessary to investigate and optimize the fuel in oil sorption and desorption processes. At the University of Applied Sciences Regensburg a new measurement technique has been developed that realizes the online analysis of the fuel quantity in the engine oil. The measurement technique enables a total as well as a selective detection of fuel hydrocarbons so that besides the detection of the total fuel amount in the oil it is also possible to study the sorption and desorption behavior of single fuel components into and out of the oil. Investigations were carried out with the measurement technique on gasoline and diesel engines at engine operating conditions with high oil dilution risk. The main focuses were for gasoline engines on the study of cold start and warm up behavior of the engine under cold ambient conditions with fuels containing varying amounts of ethanol and for diesel engines on the study of late injection strategies for particulate filter regeneration.
Artmann, Christina, Kaspar, Marcel, Rabl, Hans-Peter, Mayer, Wolfgang
The Study on Catalyst Light-Off Time and Emission Reduction of Turbo Gasoline Direct Injection EU5 Exhaust System2013-01-260810/14/2013
The future powertrain development is characterized by better fuel economy. To meet this, using turbo system in the engine is becoming more frequent in the vehicle development. But using turbo in the engine is only good for power and fuel economy, and not good for emission. That is because the turbo equipped engine loses lots of heat energy at the cold start due to the turbo mass. And thus for turbo engine, it is required to apply the technologies to shorten the catalyst light-off time to reduce the exhaust emissions. Especially when the turbo equipped vehicle is tested on NEDC cycle which is tested on urban low speed cycle at the start of the cycle, its emission is too much to meet the Euro5 regulation. This paper investigates the successful ways to reduce the catalyst light-off time and exhaust emissions to meet the EU5 emission regulation in turbo gasoline direct injection(Turbo GDI) engine. So we do the comprehensive emission tests like increasing the precious metal and cell density, shortening the distance to the catalyst and applying additional device like secondary air. With these diverse tests, we come closer to meeting the EU5 emission.
Jang, ChunSoon, Kim, Sangbeom, Park, Cheolho
Optimization of Cold Start Operating Conditions in a Stoichiometric GDI Engine with Wall-guided Piston using CFD Analysis2013-01-265010/14/2013
The purpose of this paper is to investigate the mixture formation and optimize the operating conditions under cold start in a stoichiometric (λ=1) GDI engine with wall-guided piston using a 3D commercial code, STAR-CD [8]. For GDI engine under cold start, it can be difficult to carry out the optimization of operating conditions by engine test alone without the understanding of mixture formation inside the combustion chamber. In this study, three cold start conditions of the catalyst heating mode with split injection, the cranking under freezing temperature and acceleration before engine warm-up which causes oil dilution were calculated. In particular, injection strategy for each cold start condition were optimized and compared to the engine test data. The previously validated spray models [6] were applied to the analysis of the spray formation and mixing process inside the combustion chamber. Also, Bai's droplet-wall interaction model and liquid film model considering the film stripping on the surface were used for better prediction of wall film behavior. This approach reasonably predicts the interaction of the injected spray and the in-cylinder flow, the mixture distribution around the spark plug, and liquid film on the wall inside the combustion chamber. The analysis results show that under cold start with relatively low engine speed, injection parameters such as pressure, split injection ratio and timing strongly affect tumble flow, mixture formation and wall wetting. The results for the optimized injection conditions are qualitatively in good agreements with experimental data in terms of combustion stability (RPM variation), HC emission, and oil dilution.
Kim, Sung-Jun, Hyun, Soungjae, Park, JaeIn
150 Watt Constant Voltage LED DriverTBMG-169477/1/2013
Green Watt Power, a division of Calex Mfg. Co. (Concord, CA), recently introduced the GLV-24-150, a constant voltage LED power supply with a universal AC input range, 100 - 277 VAC. The GLV-24-150 has an output voltage of 24 VDC at 6.25 Amps. The unit is housed in an IP67 rated fully encapsulated enclosure measuring 8.98" × 2.83" × 1.73" (228mm × 80mm × 45mm). The GLV case has flanges for convenient mounting and flying leads are available making the unit suitable for a variety of interconnect requirements.
Cold and Warm Start Characteristics using HVO and RME Blends in a V6 Diesel Engine2013-01-13064/8/2013
The first several cycles determine the quality of an engine start. Low temperatures and air/fuel ratio cause incomplete combustion of the fuel. This can lead to dramatic increases in HC and PM emissions. In order to meet Euro V legislation requirements which have stricter cold start emission levels, it is critical to study the characteristics of cold and warm starting of engines in order to develop an optimized operation. The NO and THC emissions were measured by fast CLD and Fast FID gas analyzers respectively and PM in both nucleation and accumulation modes were measured by DMS500. The coolant temperature was controlled in order to guarantee the experiment repeatability. The results show that at cold start using RME60 produced higher NO and lower THC than the other tested fuels while combustion of HVO60 produced a similar level of NO but lower THC compared with mineral diesel. Meanwhile, the nucleation mode of mineral diesel was similar to RME60 but higher than HVO60. The accumulation particle of using mineral diesel was higher than RME60 but lower than that of HVO60. As the engine coolant temperature increased to 90°C, the NO emission of each fuel was increased by varying amounts. THC and PM of all fuels were decreased except for HVO60 which increased THC and nucleation mode PM dramatically.
Liu, Dai, Xu, Hongming, Tian, Jianyi, Tan, Cheng, Li, Yanfei
Fault Tolerance Characteristics of FlexRay Central Devices2013-01-11854/8/2013
FlexRay is a communication system targeted at, among other things, fault tolerant applications. In contrast to some other communication systems, FlexRay systems often contain a central device such as an active star. Due to their ability to isolate portions of the communication system central devices offer opportunities to mitigate certain faults. This paper presents several alternatives for the central device of a FlexRay system, specifically active stars, FlexRay switches, and Central Bus Guardians. The paper analyzes the fault detection, isolation and mitigation mechanisms of each central device based on available documentation and specifications.
Gupta, Amit, Jochim, Markus, Orlando, Kenneth
Cold Start Concept (CSC™): A Novel Catalyst for Cold Start Emission Control2013-01-05354/8/2013
Catalytic emission control systems are installed on nearly all automobiles and heavy-duty trucks produced today to reduce exhaust emissions for the vehicles to meet government regulations. Current systems can achieve very high efficiencies in reducing tailpipe emissions once the catalytic components reach their operating temperatures. They are, however, relatively ineffective at temperatures below their operating temperature windows, especially during the cold start period of the vehicles. With the increasingly stringent government regulations, reducing the emissions during the cold start period before the catalytic components reach their operating temperatures is becoming a major challenge. For cold start HC control, HC traps based on zeolites have been investigated and commercialized for certain applications. For cold start NOx control, especially in lean burn engine exhaust, NOx storage and release catalysts have been evaluated. In this paper we will introduce a novel catalyst which we refer to as Cold Start Concept (CSC™) catalyst technology. This cold start catalyst not only stores HC and NOx at low temperatures with very high storage efficiencies, but also converts a significant portion of the stored HC/NOx during the warm-up period before the rest of the HC/NOx is thermally released from the catalyst. The HC/NOx release temperature in a cold start catalyst is high enough that the released HC/NOx can be further converted by the downstream catalytic components. In addition, the cold start catalyst also exhibits excellent CO, HC, and NO oxidation activity under normal lean conditions. Both laboratory and engine evaluation results of this new concept will be presented.
Chen, Hai-Ying, Mulla, Shadab, Weigert, Erich, Camm, Kenneth, Ballinger, Todd, Cox, Julian, Blakeman, Phil
Plastic Welding Process Signature2012-36-016210/2/2012
The following article describes a method developed to control the ultrasonic fuel rail welding. It is done monitoring some physical phenomena during the process, like vibration amplitude, welding energy and its duration. Based on statistical analysis, durability and aging tests on a great population of manufactured parts, it was possible to classify those parameters and build a real time filter capable to segregate bad parts in less than one second, just after process is done. This way, it is possible to purge the bad parts before spending more time and resources in a nonconforming segment.
Cavaglieri, Marcelo R., Figueiredo, Filipe A., Cardia, Fabiano, dos Reis, Geraldo
Cold Start Calibration of Current PZEV Vehicles and the Impact of LEV-III Emission Regulations2012-01-12454/16/2012
The cold start calibration of five different four cylinder Partial Zero Emission Vehicle (PZEV) vehicles are examined. This subset of PZEV vehicles with engine displacements between 2.0 and 2.4L, include direct injection and port fuel injection applications with and without secondary air injection. Calibration parameters such as ignition timing, engine speed, and air-to-fuel ratio of each vehicle are compared. Converter light-off strategies differ drastically during Federal Test Procedure (FTP) cold start with various combinations of high engine idle speeds, aggressive ignition retard, secondary exhaust air injection, and in the case of direct injected (DI) engines, split fuel injections. Emission studies were performed on two of the PZEV vehicles to determine the required platinum group metals (PGM) needed to achieve Super Ultra Low Emission Vehicle (SULEV) SULEV20 and SULEV30 Low Emission Vehicle (LEV) LEV-III emissions requirements. It was determined that the placement of PGM and advanced catalyst technologies are critical for low cost emission solutions. In summary, combining the non-methane organic gases (NMOG) and nitrous oxides (NOx) standards for the LEV-III proposed standards do not require new emission solutions for current PZEV calibrated vehicles. In some cases the combined standard may be easier to achieve than the current 10 wt. mg/mile NMOG PZEV standard.
Ball, Douglas, Moser, David
Delphi's Heated Injector Technology: The Efficient Solution for Fast Ethanol Cold Starts and Reduced Emissions2012-01-04184/16/2012
Most current flex-fuel vehicles are capable of operating on gasoline/ethanol blends from E0 to E85. The presence of gasoline in the fuel enables cold startability because some of its more volatile components can still vaporize at cold temperatures and produce an ignitable mixture. However when E100 is used, other means are required for cold starting because of ethanol's relatively low vapor pressure at low temperatures. A common technique is to employ an auxiliary gasoline fuel system for use only when temperatures are too low for the vehicle to start on E100 alone. But the added cost, complexity and maintenance of such systems have driven the search for a simpler approach. One such technique is to heat the fuel prior to injection. Fuel systems currently exist where heating occurs within the main conduit of the fuel rail. Another method is to heat the fuel within each fuel injector. A common misconception is that heating the fuel locally at the injector does not create a sufficient quantity of heated fuel capable starting and maintaining engine operation until the engine can run on unheated fuel. This paper offers a summary of Delphi's development of a viable heated injector system. Along with injector design optimization techniques, vehicle test results showing improved cold start times and reduced emissions are presented. These efforts have helped produce an injector design and control strategies yielding improved ethanol cold start times compared with existing heated rail systems. Consequently, heated injector production is scheduled to begin during the second quarter of 2012.
Spegar, Timothy D., Burke, David, Lavan, Lucille
Cold Start Simulation and Test on DISI Engines Utilizing a Multi-Zone Vaporization Approach2012-01-04024/16/2012
Recent years have witnessed a dramatic increase in global ethanol production, while cellulosic feedstock or the algae-based production approach make more sustainable ethanol production foreseeable in many countries. The ethanol produced will increasingly penetrate the markets not only as blending component, but also as main fuel component, boosting demand for flex-fuel vehicles. One of the main challenges for flex-fuel vehicles is the cold start due to the poor vapor pressure of ethanol. This is detrimental to starting capability in DISI engines in particular, with increased cylinder wall wetting causing higher oil dilution. The most efficient solution for DISI engines is a smart injection strategy, enabling fuel vaporization during injection in the compression stroke. But this requires optimum injection parameters such as injection timing, split ratio and rail pressure. A quasi-dimensional engine start simulation model was developed to drastically reduce the experimental workload involved in cold start realization and optimization. It permitted efficient investigation of the impact of parameters such as fuel vaporization properties, injection parameters, cam profiles and boundary conditions such as temperature and pressure. The model was based on a one-zone approach and ignored the temperature differences in the combustion chamber during mixture formation, resulting in poor quantitative accuracy of the required fuel mass. A new approach described in this paper has introduced a multi-zone model, considering different conditions for vaporization in the spray zone compared to pure air zone. Vaporization in the spray zone significantly reduces the temperature there, especially for fuels with high vaporization heat, e.g. alcohols, following the withdrawn heat of vaporization. The result is a notable delay in vaporization, an effect which must be considered by simulation tools. The multi-zone approach was introduced to the existing one-zone simulation model. The model then formed the basis for estimating optimum injection parameters (timings, split ratios, pressures) for certain cold start temperatures. Subsequent engine tests showed a good correlation between simulation and experimental results particularly for low temperatures. A multi-zone vaporization model that incorporates spray volume data is thus recommended for efficient cold start optimization.
Liebsch, Stephan, Zboralski, André, Maass, Jochen, Guenther, Michael, Kratzsch, Matthias, Zwahr, Steffen
Measurement of Automobile Exhaust N 2 O in Continuous Dilute and in Sample Storage Bag by a Mid-IR Laser Spectroscopic Motor Exhaust Gas Analyzer2012-01-08754/16/2012
Nitrous oxide (N₂O) emission reduction has gained large prominence recently due to its contribution to the climate change as a greenhouse gas. The United States Environment Protection Agency (US-EPA) together with the United States Department of Transport (DOT) has already regulated the N₂O emissions from light-duty vehicles (LDV) to 0.010 g/mile. For LDV, N₂O measurement should be done from sample storage bags over the light-duty FTP drive cycles. N₂O emission standard of 0.10 g/bhp-hr for heavy-duty engines (HDE) is also finalized. The final N₂O standard becomes effective in 2014 model year for diesel engines. Usually raw or diluted exhaust is measured for HDE emission testing. Therefore, an analyzer capable of measuring N₂O from bag and from diluted sample continuously is required to support both LDV and HDE regulations. Nondispersive infrared (NDIR) analyzer, Fourier transform infrared (FTIR) analyzer, Laser infrared analyzer, Photoacoustic analyzer (PAS), and Gas chromatograph (GC) analyzer have been recommended for N₂O measurement. In the previous study, the authors had developed an instrument based on mid-infrared laser spectroscopy for measuring ultra-low level N₂O in automobile exhaust gas sampled in a sample storage bag. In this study, comparative measurement of automobile exhaust N₂O in continuous dilute and in sample storage bag has been attempted. A modern vehicle meeting 2008 Japanese emission standards has been evaluated. Tests are conducted on a chassis dynamometer cell under different test cycles. In addition, verification of the interference of co-existing gases commonly observed in automobile exhaust gas has also been performed. In this study, it is found that the laser-based exhaust gas analyzer has sufficient detection capability for bag measurement and fast response for continuous dilute measurement. There is no interference caused by CO, CO₂, and H₂O usually observed in the automobile exhaust gas in significantly amount and have absorption in the same wavelength region as of N₂O used in this analyzer. The test vehicle emits very low N₂O and most of them are emitted within first 100 seconds of the FTP driving cycle when tested under cold start condition.
Rahman, Montajir, Hara, Kenji, Nakatani, Shigeru
Real World Cold Start Emissions from a Diesel Vehicle2012-01-10754/16/2012
This study uses on-board measurement systems to analyze emissions from a diesel engine vehicle during the cold start period. An in-vehicle FTIR (Fourier Transform Inferred) spectrometer and a Horiba on-board measurement system (OBS-1300) were installed on a EURO3 emission-compliant 1.8 TDCi diesel van, in order to measure the emissions. Both regulated and non-regulated emissions were measured, along with an analysis of the NO/NO₂ split. A VBOX GPS system was used to log coordinates and road speed for driving parameters and emission analysis. Thermal couples were installed along the exhaust system to measure the temperatures of exhaust gases during cold start. The real-time fuel consumption was measured. The study also looks at the influence of velocity on emissions of hydrocarbons (HCs) and NOx. The cold start period of an SI-engine-powered vehicle, was typically around 200 seconds in urban driving conditions. The results of this research show that the cold start period for the diesel engine is shorter than that for the SI engine. Emissions of CO, NO, NO₂, formaldehyde and total hydrocarbons (THCs) were higher during the cold start period than the warmed up period. The magnitude of increase during the cold start was smaller than SI engines. NOx emissions under real-world driving conditions were well above the legislated values. The study of velocity and emissions also found a correlation between emissions of HCs and NO with vehicle velocity, showing a trend of higher speed alongside higher emissions.
Windeatt, Jayne, Brady, Gemma, Usher, Philippa, Li, Hu, Hadavi, Ali
Excess Emissions and Fuel Consumption of Modern Spark Ignition Passenger Cars at Low Ambient Temperatures2012-01-10704/16/2012
Cold starts are demanding events for spark-ignition (SI) internal combustion engines. When the temperatures of the engine oil, coolant and the engine block are close to the ambient temperature, start-up can be difficult to achieve without fuel enrichment, which results in significant excesses in exhaust emissions and fuel consumption. In general, the lower the ambient temperature, the more substantial these problems are. Many nations frequently experience sub-zero ambient temperatures, and the European Union (among others) has specified an emissions test at low ambient temperature (-7°C). Passenger cars typically experience one to two cold start events per day, and so both cold starts and the warm-up period that follows are significant in terms of exhaust emissions. This paper examines emissions at low ambient temperatures with a special focus on cold start; emissions are also compared to start-up at a higher ambient temperature (24°C). The causes of excess emissions and fuel consumption are briefly discussed. A series of tests were performed on European passenger cars on a chassis dynamometer within an advanced climate-controlled test laboratory at BOSMAL Automotive Research and Development Institute, Poland. Emissions data obtained over the Urban Driving Cycle by testing at 24°C and at -7°C, are presented for a selection of modern Euro 5 gasoline vehicles representative of the European passenger car fleet. A full modal emissions analysis was also conducted at 24°C and at -7°C over the New European Driving Cycle. Emissions and fuel consumption were substantially higher at -7°C than at 24°C.
Bielaczyc, Piotr, Szczotka, Andrzej, Woodburn, Joseph
Low Temperature Starting Techniques for Ethanol Engine without Secondary Fuel Tank2011-32-055211/8/2011
The present study aims to investigate the parameters affecting cold start characteristics of ethanol at low temperature, and suggest a solution to avoid cold starting problem without the installation of second fuel tank. The testing engine is a 125cc volume displacement, single-cylinder four strokes SI engine with fuel injection and ignition timing system controlled by ECU (electronic control unit). The cold starting performance tests were extensively conducted with different percentages of ethanol blends, surrounding temperatures, heating inside combustion chamber, heater injector, pre-cranking without fuel injection, and amount of fuel injection. From the experimental results, when using ethanol fuel in conventional engine, the problem of cold starting was observed at surrounding temperature lower than 20°C for ethanol. Increasing of injection duration can lower the possible cold start temperature of neat ethanol. Glow plug and pre-cranking heating methods can help the engine start at much lower temperature. The combination of many techniques can make the ethanol engine start at the temperature as low as 3.5°C. These findings offer solutions to the cold start problem in engine fueled with neat ethanol fuel in Thailand.
Charoenphonphanich, Chinda, Imerb, Wittawat, Karin, Preechar, Chollacoop, Nuwong, Hanamura, Katsunori
Transistor Coil Ignition System for Kick Start Based Small Engines2011-32-061311/8/2011
Two wheeler 4-stroke small Engine with Kick Start requires longer spark duration along with better spark energy in order to burn the lean mixture and to have better Start ability, lower trigger start RPM is also important to enable ease of start. An effective Ignition System needs to be designed for the above purpose. Hence Transistor Controlled Ignition/Inductive Discharge System (TCI/IDI) unit is preferred which gives all the above mentioned requirements. Normally any conventional TCI/IDI operated 4-stroke two wheelers will have D.C power line align with a Power Source for its operation. The 2 Wheeler Kick start version cannot afford the DC Power Source due to Cost, Hence the Electrical System will not have the DC Power Line. So it is not possible to operate a Conventional TCI/IDI system as it is DC Power based System. The challenge is to operate the TCI/IDI ignition unit without DC Power Source i.e. using AC Source. In order to prove the above concept extensive data were collected on the charging pattern and power consumption during operation of various loads with existing charging system. Based on the collected data and customer usage pattern, appropriate power requirement characteristic graphs are obtained. Hence New TCI/IDI has been designed with longer Spark duration and Less Trigger Start RPM. Finally proto parts are developed as per the required power characteristic and then the system was tested on proto engines. This new system* delivers the attributes of a TCI/IDI ignition unit required for a 4-stroke two wheeler engine without using a DC Power Source i.e. only Kick Start. This is having a huge impact on the reduction of Vehicle electrical system cost as DC Power Source is one of the major cost driver for any electrical system with IDI/TCI ignition unit for better performance. Hence it increases the effective efficiency than Conventional Ignition System designed for Kick Start based small Engines.
Sivakumar, A., Mazumdar, Dipanjan, Jabez Dhinagar, S.
Testing Performance of Fuel Cell Systems for Automotive ApplicationsJ2615_201110 (Current)10/20/2011
This recommended practice is intended to provide a framework for performance testing of fuel cell systems (FCS’s) designed for automotive applications with direct current (DC) output. The procedures described allow for measurement of performance relative to claims by manufacturers of such systems with regard to the following performance criteria. — Power — Efficiency — Transient Response — Start and Stop Performance — Physical Description — Environmental Limits — Operational Requirements — Integration Since this recommended practice is based on the principal of performance measurement relative to a claim, the testing parties should take care to include any qualifying or unique circumstances leading to the test results reported in order to achieve full disclosure. For example, efficiency as defined in section 3.1.9 allows for the inclusion of thermal output benefit. If a test result is reported which takes advantage of this allowance this stipulation should be noted with the efficiency figure and the useful purpose of the thermal output (e.g. cabin heating) should be made clear.
Fuel Cell Standards Committee
Items per page:
1 – 50 of 333