Browse Topic: Boost pressure

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DoE-Based Numerical Optimization of Intake and Exhaust Port Geometry of a Small Opposed-Piston 2-Stroke (OP2S) Hydrogen Engine2024-32-005404/18/2025
The future potential of an opposed-piston two-stroke (OP2S) engine has attracted the attention of researchers worldwide as it offers a high thermal efficiency and power-to-weight ratio with a simple engine configuration. This engine can be used with low-carbon fuels and hydrogen to reduce greenhouse gas emissions. However, the two-stroke operation has always been limited by its low scavenging efficiency and short-circuit of fresh charge. The current work is focused on optimizing scavenging efficiency and short-circuit in a small 200 cc single-cylinder OP2S SI engine using 3-D computational fluid dynamic (CFD) simulations. The effect of four parameters, namely, area of intake ports, area of exhaust ports, and angular orientations of intake ports (swirl and tilt) on scavenging efficiency and short-circuit, has been assessed and optimized. A Latin-hypercube based Design of Experiments (DoE) methodology is used to sample the design space spanning over a range of four parameters. A response
Singh, Saurabh, Boggavarapu, Prasad, Himabindu, M., Ravikrishna, R.V.
Simulation Study on EGR Condensate Flow and Uniformity of Each Cylinder in the Intake Manifold2023-01-703410/30/2023
As engine technology developed continuously, engine with both turbocharging and EGR has been researched due to its benefit on improving the engine efficiency. Nevertheless, a technical issue has raised up while utilizing both turbocharging and EGR at the same time: excess condensed water existed in intake manifold which potentially trigger misfire conditions. In order to investigate the root-cause, a CFD model (conducted by CONVERGE CFD software) was presented and studied in this paper which virtually regenerated intake manifold flow-field with EGR condensed water inside. Based on the simulated results, it concluded that different initial conditions of EGR condensed water could significantly change the amount of water which deposited in each cylinder. Thus, a coefficient of variation of deposited condensed water amount among these cylinders, was marked as the evaluation reference of cylinder misfire. Theoretically, as this coefficient of variation reduced, the EGR condensed water from
Pan, Shiyi, Li, Guanting, Wang, Jinhua, Zhang, Nan, Xu, Zhiqin, Chen, Shanghua, Chen, Jun, Zhao, Shengwei
Simulation Study on High Expansion Ratio Dedicated Hybrid Engine for Hybrid Commercial Vehicle Application2023-01-700510/30/2023
The fuel economy and emission of the hybrid vehicle depend largely on the selected engine. And the dedicated hybrid engine (DHE) can be controlled to operate in the optimal operating range because DHE can be decoupled from the vehicle transmission system. The main purpose of this paper is to improve the thermal efficiency of the diesel engine under common operating conditions combined with high compression ratio (CR) and early or late intake valve closing (IVC) angle. According to the vehicle road spectrum data, the optimal operating range of the engine is determined to be 1200-1400 rpm and 70%-90% load. Then CR and IVC angle are optimized by using the calibrated one-dimensional thermodynamic model of the engine under limited peak combustion pressure (Pmax). The results show that the adjustment of IVC angle and CR can control the thermal state at the end of compression stroke. The combination of CR and IVC angle can achieve the optimal fuel consumption improvement. The minimum brake
Wang, Xiaosa, Lin, Zhiqiang, Wang, Hu, He, Hua, Liang, Depu
Saw-Tooth Ramps for the Suppression of Flow-Acoustic Coupling in a High-Frequency Silencer for Turbocharger Compressors2025-01-002305/05/2023
The ported shroud casing treatment for turbocharger compressors is desirable for mitigating broadband/whoosh noise and enhancing boost pressures at low to mid flow rates. Yet, it is accompanied by elevated narrowband noise at the blade-pass frequency (BPF). Compressor BPF noise occurs at high frequencies where wave propagation is often multi-dimensional, rendering traditional planar wave silencers invalid. An earlier work introduced a novel reflective high-frequency silencer (baseline) targeting BPF noise in the 8-12 kHz range using an “acoustic straightener” that promoted planar wave propagation along arrays of quarter-wave resonators (QWRs). The design, however, faced challenges with high-amplitude tonal noise generation at specific flow conditions due to flow-acoustic coupling at the opening of the QWRs, thereby compromising the noise attenuation. The current study explores two QWR interface geometries that weaken the coupling, including linear and saw-tooth ramps on the upstream
Sriganesh, Pranav, Selamet, Ahmet
A Model-Based Investigation of Electrically Split Turbocharger Systems Capabilities to Overcome the Drawbacks of High-Boost Downsized Engines2022-01-505207/20/2022
Engine downsizing is one the most common methods of coping with strict emission regulations. However, it must be coupled with complementary systems so that the engine performance would meet the standards. That is why new efficient solutions can pave the way toward this goal. The electric forced-induction system (EFIS) is the emerging replacement for conventional forced-induction systems (FIS), namely, turbochargers and superchargers. The reason behind this replacement is the drawbacks associated with FIS, among them are turbo lag and inefficiency in exhaust gas energy recycling. Electrically split turbocharger (EST) is a form of EFIS which offers a great potential for engine downsizing. In this paper, a new approach to EST utilization for lowering the fuel consumption (FC) without compromising performance has been introduced, through which the augmented degree of freedom enabled by an EST is used to optimize the air-charge boosting. To show the effectiveness of the proposed method, a
Kouhyar, Farzad, Nikzadfar, Kamyar
Air management system for hydrogen-fueled internal combustion engine – learning from the past2022-01-071703/29/2022
The internal combustion engine (ICE) has undergone a drastic technological change in the past 20 years. From downsizing in the 2000s to electrification in the 2010s, all changes aimed to achieve a better fuel economy with lower emissions. However, in the age where a majority of the countries are pursuing carbon neutrality, ICE is facing a whole new challenge ahead – renewable hydrogen fuel. A completely different combustion characteristic means the turbocharger on a hydrogen-fueled ICE (H2ICE) needs to operate in a distinctive condition. Nonetheless, many turbocharger designs learnt in the past two decades are still applicable to this new ICE architecture. This paper presents a preliminary study on the feasibility of using turbine technologies developed in the past for fossil-fueled ICE in a hydrogen-fueled unit. It provides a glimpse of potential air management system configuration that can potentially be used in an H2ICE. The paper begins by understanding the new operating condition
Chiong, Meng Soon, Rajoo, Srithar, Kim, Jeyoung, Martinez-Botas, Ricardo, Fujita, Yutaka, Yokoyama, Takao, Ebisu, Motoki
3-Dimentional Numerical Simulation and Research on Flow Distribution Unevenness in Intake Manifold for a Turbocharged Diesel Engine2022-01-023403/29/2022
The design of engine intake system affects the intake uniformity of each cylinder of the engine, which in turn has an important impact on the engine performance, the uniform distribution of EGR exhaust gas and the combustion process of each cylinder. In this paper, the constant-pressure supercharged diesel engine intake pipe is used as the research model to study the intake air flow unevenness of the intake pipe of the supercharged diesel engine. The pressure boundary condition at the outlet of each intake manifold is set as the dynamic pressure change condition. The three-dimensional numerical simulation of the transient flow process in the intake manifold of diesel engine is simulated and analyzed by using numerical method, and the change of the internal flow field in the intake manifold under different working conditions during the intake overlapping period is discussed. The dynamic effects of diesel engine intake boost pressure, rotated speed, and intake pipe geometrical
Yang, Shuai, Yan, Kai, Liu, Haifeng, Liu, Hairan, Li, Tong
Turbocharger Turbine for Charging a Lean-Burn Gasoline Engine2022-01-045203/29/2022
Lean-burn combustion is a promising technology for reducing fuel consumption and CO2-emissions of gasoline engines. Due to the air dilution, the indicated engine efficiency increases, resulting in lower fuel consumption and less CO2-emissions. However, the air dilution decreases the combustion temperature, which leads to increased demands on the charging system. In order to map the same engine operating point, higher boost pressures are required at lower available exhaust enthalpy. This places high efficiency requirements on the turbocharger. Hence, state of the art single-stage turbochargers are unable to provide enough boost pressure to enable lean-burn over a sufficiently wide engine operating range. In this paper, a single-stage turbocharger turbine is developed with the objective of enabling a lean-burn engine operation with an air-fuel ratio of λ=2 in the range of the Worldwide Harmonized Light-Duty Vehicles Test Cycle (WLTC). For this purpose, extensive 1D-engine simulations are
Sagan, Lukas, Kuestner, Christoph, Eilts, Peter, Seume, Joerg
Determination of Shock Induced loads on Waste Gate Valves for Heavy Duty applications2022-01-071403/29/2022
The turbocharger used with an engine is conventionally equipped with a Waste Gate (WG) valve to control the mass flux of air supplied to the intake system. A WG valve is actuated according to a defined and constant maximum boost pressure downstream of the compressor in the whole engine operating range and directly controls the maximum power the engine can supply. In heavy industrial applications, the WG valve is often subjected to failure because of several reasons. In the present study, the formation of shocks in the region near the valve has been explored as a probable cause for the failure. Furthermore, flow-induced transience near the WG leads to valve flutter which may resonate with the natural frequency of the control mechanism resulting in an abject breakdown. The commercial code of Fluent® has been optimized to predict the intensity of shocks formed near the WG. Both RANS and LES based solver algorithms have been explored to model the valve flutter in terms of the moment
Varshney, Anchal, Bourothu, Pavan
Strategies for Reduced Engine-out HC, CO, and NOx Emissions in Diesel-Natural Gas and POMDME-Natural Gas Dual-Fuel Engine2022-01-055903/29/2022
Dual-fuel engines employ precisely metered amounts of a high reactivity fuel (HRF) such as diesel at high injection pressures to burn a low reactivity fuel (LRF) such as natural gas, which is typically fumigated into the intake manifold. Dual fuel engines have demonstrated the ability to achieve extremely low engine-out oxides of nitrogen (NOx) emissions compared to conventional diesel combustion at the expense of unburned hydrocarbon (HC) and carbon monoxide (CO) emissions. At low engine loads, due to the low in-cylinder temperatures oxidation of HC and CO is challenging. This results in both compromised combustion and fuel conversion efficiencies. The experimental campaign discussed in this paper consisted of a set of six basic engine control parameters that were strategically varied to find the best possible efficiency-emissions trade-offs for both diesel- and poly-oxy methylene dimethyl ether (POMDME)-natural gas fuel combinations on the University of Alabama single-cylinder
Hariharan, Deivanayagam, Partridge, Kendyl, Narayanan, Abhinandhan, Anandaraman, Nandagopalan, Srinivasan, Kalyan, Krishnan, Sundar Rajan
Feasibility study of boosted DI technology for sport motorcycle2022-32-007901/09/2022
The sport motorcycles continue to provide riders with the riding pleasure by the excellent potential of mobility performance brought by lightweight, compactness and high-performance powertrains. However, we are in a situation where we need to make efforts to reduce CO2 emission as much as possible on a global scale, and we also need to make serious efforts to reduce CO2 emission for sport motorcycles. The challenge for sport motorcycles from this perspective is a drastic improvement in fuel efficiency while maintaining the "vehicle dynamic performance", "drivability performance" and "to meet the latest exhaust emission regulation", and Yamaha has been proceeding the several feasibility studies aiming for realizing this challenge as advanced development. In one of the feasibility studies, "Downsizing Concept with boosted DI technology," we developed a research motorcycle equipped with a powertrain that achieved a specific output of 156kW / L (133kW / 0.85L) on a sport motorcycle. As a
Sato, Hayatoshi, Torigoshi, Masaki, Takase, Hiroki, Makita, Naoki
Fuel Stratification Effects on Gasoline Compression Ignition with a Regular-Grade Gasoline on a Single-Cylinder Medium-Duty Diesel Engine at Low Load2021-01-117309/21/2021
Prior research studies have investigated a wide variety of gasoline compression ignition (GCI) injection strategies and the resulting fuel stratification levels to maintain control over the combustion phasing, duration, and heat release rate. Previous GCI research at the US Department of Energy’s Oak Ridge National Laboratory has shown that for a combustion mode with a low degree of fuel stratification, called “partial fuel stratification” (PFS), gasoline range fuels with anti-knock index values in the range of regular-grade gasoline (~87 anti-knock index or higher) provides very little controllability over the timing of combustion without significant boost pressures. On the contrary, heavy fuel stratification (HFS) provides control over combustion phasing but has challenges achieving low temperature combustion operation, which has the benefits of low NOX and soot emissions, because of the air handling burdens associated with the required high exhaust gas recirculation rates. This work
Curran, Scott, Szybist, James, Kaul, Brian, Easter, Jordan, Sluder, Scott
Time to boost analysis of an advanced boosting system for automotive applications2021-24-009309/05/2021
Fun to drive and drivability are important issues in modern vehicles, and propulsion system plays a key role in achieving these goals. Nowadays, most engines are characterized by the presence of a turbocharging system in order to obtain a high level of specific power and efficiency. Unfortunately, turbocharged engines are characterized by a delay in toque delivery, especially at low load, a phenomenon commonly called turbo-lag. In this paper an innovative turbocharging system is studied with the aim of providing a solution to this annoying behavior; a hybrid bosting system consisting of a traditional turbocharger and an electrically assisted compressor is analyzed. This architecture, especially thanks to the good dynamic behavior of the e-compressor, achieves the goal of an important reduction in terms of time-to-boost, providing an important improvement in engine readiness. The experimental campaign is carried out entirely on the test bench for components of the propulsion system of
Usai, Vittorio, Marelli, Silvia
Regulated Intake Air Boosting and Engine Downspeeding as a Viable Solution for Performance Improvement and Emission Reduction of a Single-Cylinder Diesel Engine03-15-02-000908/16/2021
The present work proposes a viable approach to develop single-cylinder diesel engines for the future by implementing regulated intake air boosting (RIAB) and engine downspeeding (ED) along with the well-established low compression ratio (LCR) approach. The investigations were conducted in a mass-production light-duty single-cylinder diesel engine initially equipped with a naturally aspirated (NA) intake system. By lowering the compression ratio (CR) and implementing the intake air boosting (IAB) using a belt-driven supercharger, the maximum brake mean effective pressure (BMEP) of the engine could be increased by 50%. More importantly, the improved performance could be achieved without violating the peak firing pressure (PFP) limits. However, a significant penalty was observed in the brake-specific fuel consumption (BSFC) at low-load operating points due to the additional power consumption of the IAB system. Hence, RIAB was implemented to optimize the boost pressure with respect to
Vikraman, V., Krishnasamy, Anand, Ramesh, A.
Power and Torque Determination for UAS Engines Having Maximum Power Ratings at or Below 22.4 kWARP6971 (Current)04/07/2021
This recommended practice is applicable to reciprocating engines powering unmanned aerial vehicles (UAV) having rated power values less than 22.4 kW, and which are not to be used for human transport.
E-39 Unmanned Aircraft Propulsion Committee
Power and Torque Determination for UAS Engines Having Maximum Power Ratings at or Below 22.4 kWARP6971-TEST-REC (Historical)04/07/2021
This recommended practice is applicable to reciprocating engines powering unmanned aerial vehicles (UAV) having rated power values less than 22.4 kW, and which are not to be used for human transport.
E-39 Unmanned Aircraft Propulsion Committee
7.0.101 - A New Image De-hazing Method for Safety Critical ADAS ApplicationsSAE-PP-0027702/04/2021
Driver safety and Advanced Driver Assistance Systems (ADAS) is gaining lot of importance these days. In some countries, there are strict regulations in place which mandate the use of certain ADAS features in automobiles. However, as the need for these safety critical systems increases, the challenges associated also increase. These challenges can arise due to technology, human factors or due to nature. In countries like India, where one can expect different weather conditions with changing geography, the associated challenges are mainly due to the natural factors like haze, fog, rain and smoke. This poses a challenging problem in terms of visibility for the drivers as well as in vision based ADAS; thereby, leading to many fatal road accidents. In this paper, a novel pre-processing technique, which addresses the interesting problem of enhancing the perceptual visibility of an image that is degraded by atmospheric haze, is proposed. The solution to this problem is presented by combining
Lname, Fname
6.0.116 - Development of 6 Years Old Child Virtual Model by Automatic ScalingSAE-PP-0027102/04/2021
Traffic accidents cause one of the highest numbers of severe injuries in the whole population. The numbers of deaths or seriously injured citizens prove that traffic accidents and their consequences are still a serious problem to be solved. A lot of effort is devoted to both passive and active safety systems development. The transportation standards usually define safety requirements by regulations (e.g. ECE-R94, 96/79/EC and ECE-R95, 96/27/EC in Europe) with specific dummies for children to be used. The dummies include hardware sensors for monitoring accelerations, loads and other signals and each dummy is developed for a specific scenario, but there are limitations of these dummies, such as only a specific age or calibration just for a specific test. Taking into account that the consequence of a traffic accident is highly influenced by the stature of the body, virtual human body models, including those for children, start to play a significant role because they can be scaled or even
Mutagaana, Festo
6.0.101 - Piston Sealing System Structure Design for Automobile's Lightweight Auto-TransmissionSAE-PP-0025702/04/2021
Current automobile's auto-transmission has problems of defects and cost reduction because of welding process and very complicated assembly process due to individualized transmission piston and sealing components. Also, size and heavy weight of transmission piston components are the source of low mileage because they are made of aluminum, steel material. In this study, therefore, we perform structure design for piston sealing system which integrates piston and sealing material for automobile's lightweight auto-transmission. Also performed stress analysis through finite element analysis to secure required suitable strength when internal pressure is applied after assemble.
Mutagaana, Festo
2.0.101 - Experimental Study of cooling of Continuously Variable Transmission (CVT) in ScooterSAE-PP-0021002/01/2021
The continuously variable transmission (CVT), which was conceptualized more than 500 years ago, is just now beginning to replace traditional transmissions in some automobiles. It is mostly used in scooter transmission. Engine power is transmitted to wheel through belt drive between two pulleys. The diameter of belt contact with pulley can change continuously and hence provide infinite gear ratios between driver and driven shafts. This technology leads to a smoother ride of vehicle. Heat is generated inside CVT due to friction between drive belt and clutch pulley. Amount of heat generated is even more due to clutch slippage during acceleration and deceleration. This will affect the service life of CVT components such as front movable drive (FMD), clutch pulley, clutch outer, and belt. In scooters generally, air cooling is preferred over liquid cooling. Cooling is achieved by incorporating centrifugal fan inside CVT housing. For better durability/service life, the degree of heat
Mutagaana, Festo
Preignition Rating of Spark PlugsJ549_202006 (Current)06/15/2020
This SAE Recommended Practice describes the equipment and procedures used in obtaining preignition ratings of spark plugs.
Ignition Standards Committee
Influence of Port Water Injection on the Combustion Characteristics and Exhaust Emissions in a Spark-Ignition Direct-Injection Engine2020-01-029404/14/2020
It is well known that engine downsizing is still the main energy-saving technology for spark-ignition direct-injection (SIDI) engine. However, with the continuous increase of the boosting ratio, the gasoline engine is often accompanied by the occurrence of knocking, which has the drawback to run the engine at retarded combustion phasing. Besides, in order to protect the turbine blades from being sintered by high exhaust temperature, the strategies of fuel enrichment are often taken to reduce the combustion temperature, which ultimately leads to a high level of particulate number emission. Therefore, to address the issues discussed above, the port water injection (PWI) techniques on a 1.2-L turbocharged, three-cylinder, SIDI engine were investigated. Measurements indicate that the optimization of spark timing has a significant impact on its performance. The two factors of the water substance itself and spark advance caused by the knock mitigation are trade-offs, which eventually affect
Fan, Yadong, Wu, Tianbao, Li, Xuesong, Xu, Min, Hung, David
A Real-Time Capable and Modular Modeling Concept for Virtual SI Engine Development2020-01-057704/14/2020
Spark Ignited (SI) combustions engines in combination with different degrees of hybridization are expected to play a major role in future vehicle propulsion. Due to the combustion principle and the related thermodynamic efficiency, it is especially challenging to meet future CO2 targets. The layout and optimization of the overall system requires novel methods in the development process which feature a seamless transition between real and virtual prototypes. Herein, engine models need to predict the entire engine operating range in steady-state and transient conditions and must respond to all relevant control inputs. In addition, the model must feature true real-time capability. This work presents a holistic and modular modeling framework, which considers all relevant processes in the complex chain of physical effects in SI combustion. The basis is a crank-resolved cylinder model which describes gas exchange and compression to determine the thermodynamic state and turbulence conditions
Poetsch, Christoph, Wurzenberger, Johann, Katrasnik, Tomaz
Real Time Energy Management Control Strategies for an Electrically Supercharged Gasoline Hybrid Vehicle2020-01-100904/14/2020
The high level of electric power available on a Hybrid Electric Vehicle (HEV) enables the introduction of electrical auxiliaries in addition or in substitution to the ones currently available on a conventional powertrain. Among these auxiliaries, electric Superchargers (eSC) for the improvement of the vehicle performance or electrically heated catalysts for the reduction of the light-off time of the after-treatment may dramatically affect the Energy Management System (EMS) of an HEV. Moreover, since these devices are only fluid-dynamically, but not mechanically, linked to the powertrain, they are traditionally neglected in the optimization of the powersplit between internal combustion engine and electric machines by the EMS. The aim of the current work is the development of an EMS that is able to consider in real time the overall electric energy consumption of the entire powertrain. More in detail, this activity focuses on the refinement of the Equivalent Consumption Minimization
Accurso, Francesco, Zanelli, Alessandro, Rolando, Luciano, Millo, Federico
A Holistic Approach to Develop a Common Rail Single Cylinder Diesel Engine for Bharat Stage VI Emission Legislation2020-01-135704/14/2020
The upcoming Bharat Stage VI (BS VI) emission legislation has put enormous pressure on the future of small diesel engines which are widely used in the Indian market. The present work investigates the emission reduction potential of a common rail direct injection single cylinder diesel engine by adopting a holistic approach of lowering the compression ratio, boosting the intake air and down-speeding the engine. Experimental investigations were conducted across the entire operating map of a mass-production, light-duty diesel engine to examine the benefits of the proposed approach and the results are quantified for the modified Indian drive cycle (MIDC). By reducing the compression ratio from 18:1 to 14:1, the oxides of nitrogen (NOx) and soot emissions are reduced by 40% and 75% respectively. However, a significant penalty in fuel economy, unburned hydrocarbon (HC) and carbon monoxide (CO) emissions are observed with the reduced compression ratio. Intake air boosting using a mechanically
Vellandi, Vikraman, Ramesh, A., Krishnasamy, Anand
Experimental and 1D Numerical Investigations on the Exhaust Emissions of a Small Spark Ignition Engine Considering the Cylinder-by-Cylinder Variability2020-01-057804/14/2020
This paper reports a numerical and experimental analysis on a twin-cylinder turbocharged Spark Ignition engine carried out to investigate the cylinder-to-cylinder variability in terms of performance, combustion evolution and exhaust emissions. The engine was tested at 3000 rpm in 20 different steady-state operating conditions, selected with the purpose of observing the influence of cylinder-by-cylinder A/F ratio variations and the EGR effects on the combustion process and exhaust emissions for low to medium/high loads. The experimental outcomes showed relevant differences in the combustion evolution (characteristic combustion angles) between cylinders and not negligible variations in the emissions of the single cylinder exhaust and the overall engine one. This misalignment resulted to be due to differences in the injected fuel amount by the port injectors in the two cylinders, mainly deriving from the specific fuel rail geometry. The experimental data were then used to validate a 1D
Marchitto, Luca, Teodosio, Luigi, Tornatore, Cinzia, Valentino, Gerardo, Bozza, Fabio
Assessment of the Ignition System Requirement on Diluted Mixture Spark Engines2020-01-111604/14/2020
In order to face the new challenges, spark ignition engines are evolving by following some strategies and technologies. Among them, alternative combustion processes based on the dilution of the homogeneous mixture, either with fresh air or with Exhaust Gas Recirculation (EGR), are being explored. In a higher or lower extent, these changes modify in-cylinder thermodynamic conditions during the engine operation (pressure, temperature and gas composition) thus conditioning the spark ignition system requirements that will have to evolve to become more reliable and powerful. In this framework, an experimental study on the effect of the key in-cylinder conditions on the ignition system performance has been carried out in a single-cylinder spark-ignition (SI) research engine. The study includes EGR, lambda and energizing time sweeps to assess the behavior of the engine in different operating conditions. Furthermore, various Insulated-Gate Bipolar Transistors (IGBT) and spark plugs have been
Molina, Santiago, Martin, Jaime, Novella, Ricardo, Gomez-Soriano, Josep, Padilla, Jose
Optical Diagnostics of Isooctane and n-Heptane Isobaric Combustion2020-01-112604/14/2020
Isobaric combustion has demonstrated a great potential to reach high thermodynamic efficiency in the advanced Double Compression Expansion Engine (DCEE) concept. It appears as one of few viable choices for applications with high-pressure combustion. At these conditions, releasing heat at a constant pressure minimizes the peak in-cylinder pressure and, hence, mitigates excessive mechanical stress on the engine. This study focuses on the effect of fuels on the multiple-injection isobaric combustion. A single-cylinder heavy-duty engine was utilized to test and compare the isobaric combustion with pure isooctane and n-heptane fuels. The engine was equipped with an optical piston to allow a bottom-view of the combustion chamber. The interactions of multiple injections and the combustion behavior were studied using high-speed acquisition of chemiluminescence. The examined isobaric cases have a peak pressure of 70 bar. For cases with high soot luminosity, a short band-pass filter was used to
Al Ramadan, Abdullah S., Nyrenstedt, Gustav, Ben Houidi, Moez, Johansson, Bengt
The Effect of Heavy-Duty Diesel Cylinder Deactivation on Exhaust Temperature, Fuel Consumption, and Turbocharger Performance up to 3 bar BMEP2020-01-140704/14/2020
Diesel Cylinder Deactivation (CDA) has been shown in previous work to increase exhaust temperatures, improve fuel efficiency, and reduce engine-out NOx for engine loads up to 3 bar BMEP. The purpose of this study is to determine whether or not the turbocharger needs to be altered when implementing CDA on a diesel engine. This study investigates the effect of CDA on exhaust temperature, fuel efficiency, and turbocharger performance in a 15L heavy-duty diesel engine under low-load (0-3 bar BMEP) steady-state operating conditions. Two calibration strategies were evaluated. First, a “stay-hot” thermal management strategy in which CDA was used to increase exhaust temperature and reduce fuel consumption. Next, a “get-hot” strategy where CDA and elevated idle speed was used to increase exhaust temperature and exhaust enthalpy for rapid aftertreatment warm-up. The “stay-hot” CDA strategy demonstrated increased exhaust temperatures up to 200°C while simultaneously reducing fuel consumption by 5
Morris, Andrew, McCarthy, James
Simulation Analysis of Early and Late Miller Cycle Strategies Influence on Diesel Engine Combustion and Emissions2020-01-066204/14/2020
Based on the working model of a diesel engine, the influence of 2 Miller cycle strategies-Early Intake Valve Closure (EIVC) and Late Intake Valve Closure (LIVC) on the combustion and emissions of diesel engine was analyzed. Then the working condition of each Miller cycle strategies on the engine under the rated speed was optimized through the adjust of the valve timing, boost pressure and the injection timing. The research found that both delaying and advancing the closure timing of the intake valve can decrease the pressure and temperature during compression stroke, prolonging the ignition delay. However, due to the decrease of the working media inside the cylinder, the average in-cylinder temperature and soot emissions will increase, which can be alleviated by raising the boost pressure and the resulting compensation of the intake loss. The study found that together with increasing boost pressure and delaying injection timing, both EIVC and LIVC can reduce the NOx and soot emissions
Yang, Shuai, Yang, Xiaolin, Liu, Haifeng, Feng, Zhiwei, Li, Xiuyuan
The Application of E-Fuel Oxymethylene Ether OME1 in a Virtual Heavy-Duty Diesel Engine for Ultra-Low Emissions2020-01-034904/14/2020
For long haul transport, diesel engine due to its low fuel consumption and low operating costs will remain dominant over a long term. In order to achieve CO2 neutrality, the use of electricity-based, synthetic fuels (e-fuels) provides a solution. Especially the group of oxymethylene ethers (OME) is given much attention because of its soot-free combustion. However, the new fuel properties and the changed combustion characteristics place new demands on engine design. Meanwhile, the use of new fuels also creates new degrees of freedom to operate diesel engines. In this work, the application of dimethoxymethane (OME1) is investigated by means of 1D simulation at three operating points in a truck diesel engine. The subsystems of fuel injection, air path and exhaust gas are sequentially adjusted for the purpose of low emissions, especially for low nitrogen oxides (NOx). Thanks to the inexistent soot-NOx trade-off, NOx can be considerably reduced by high exhaust gas recirculation (EGR) at a
Yang, Qirui, Grill, Michael, Bargende, Michael
MIMO Control of a Turbogenerator for Energy Recovery2020-01-026104/14/2020
Market trends for increased engine power and more electrical energy on the powergrid (3kW+), along with customer demands for fuel consumption improvements and emissions reduction, are driving requirements for component electrification, including turbochargers. GTDI engines waste significant exhaust enthalpy; even at moderate loads the WG (Wastegate) starts to open to regulate the turbine power. This action is required to reduce EBP (Exhaust Back Pressure). Another factor is catalyst protection, where the emissions device is placed downstream turbine. Lambda enrichment or over-fueling is used to perform this. However, the turbine has a temperature drop across it when used for energy recovery. Since catalyst performance is critical for emissions, the only reasonable location for an additional device is downstream of it. This is a challenge for any additional energy recovery, but a smaller turbine is a design requirement, optimized to operate at lower pressure ratios. A WAVE model of the
Petrovich, Simon, Ebrahimi, Kambiz, Kalantzis, Nikolaos, Pezouvanis, Antonios
CO2 Neutral Heavy-Duty Engine Concept with RCCI Combustion Using Seaweed-based Fuels2020-01-0808-TEST-REC04/14/2020
This paper focusses on the application of bioalcohols (ethanol and butanol) derived from seaweed in Heavy-Duty (HD) Compression Ignition (CI) combustion engines. Seaweed-based fuels do not claim land and are not in competition with the food chain. Currently, the application of high octane bioalcohols is limited to Spark Ignition (SI) engines. The Reactivity Controlled Compression Ignition (RCCI) combustion concept allows the use of these low carbon fuels in CI engines which have higher efficiencies associated with them than SI engines. This contributes to the reduction of tailpipe CO2 emissions as required by (future) legislation and reducing fuel consumption, i.e. Total-Cost-of-Ownership (TCO). Furthermore, it opens the HD transport market for these low carbon bioalcohol fuels from a novel sustainable biomass source. In this paper, both the production of seaweed-based fuels and the application of these fuels in CI engines is discussed. Ethanol and butanol are considered as the most
Seykens, Xander, Bekdemir, Cemil, Han, Jinlin, Willems, Robbert, Van Hal, Jaap
Is the “K Value” of an Engine Truly Fuel Independent?2020-01-0615-TEST-REC04/14/2020
The octane appetite of an engine is frequently characterised by the so-called K value. It is usually assumed that K is dependent only on the thermodynamic conditions in the engine when knock occurs. In this work we test this hypothesis: further analysis was conducted on experimental results from SAE 2019-01-0035 in which a matrix of fuels was tested in a single cylinder engine. The fuels consisted of a relatively small number of components, thereby simplifying the analysis of the chemical kinetic proprieties. Through dividing the original fuel matrix into subsets, it was possible to explore the variation of K value with fuel properties. It was found that K value tends to increase slightly with RON. The explanation for this finding is that higher RON leads to advanced ignition timing (i.e. closer to MBT conditions) and advanced ignition timing results in faster combustion because of the higher pressures and temperatures reached in the thermodynamic trajectory. The Livengood-Wu integral
Cracknell, Roger, Kassai, Masaharu, Shiraishi, Taisuke, Festa, Andrea, Gail, Sandro, Aradi, Allen, Shibuya, Masahiko
Numerical Investigation of the Combustion Kinetics of Partially Premixed Combustion (PPC) Fueled with Primary Reference Fuel2020-01-0554-TEST-REC04/14/2020
This work numerically investigates the detailed combustion kinetics of partially premixed combustion (PPC) in a diesel engine under three different premixed ratio fuel conditions. A reduced Primary Reference Fuel (PRF) chemical kinetics mechanism was coupled with CONVERGE-SAGE CFD model to predict PPC combustion under various operating conditions. The experimental results showed that the increase of premixed ratio (PR) fuel resulted in advanced combustion phasing. To provide insight into the effects of PR on ignition delay time and key reaction pathways, a post-process tool was used. The ignition delay time is related to the formation of hydroxyl (OH). Thus, the validated Converge CFD code with the PRF chemistry and the post-process tool was applied to investigate how PR change the formation of OH during the low-to high-temperature reaction transition. The reaction pathway analyses of the formations of OH before ignition time were investigated. It was found that in the case of PR0
Zhao, Yuanyuan, Wang, Hu, Liu, Xinlei, Liu, Daojian, Chenchen, Wang, Zhu, Hongyan, Zheng, Zunqing, Yao, Mingfa
Controlling Strategy for the Performance and NOx Emissions of the Hydrogen Internal Combustion Engines with a Turbocharger2020-01-025604/14/2020
Hydrogen fuel is a future energy to solve the problems of energy crisis and environmental pollution. Hydrogen internal combustion engines can combine the advantage of hydrogen without carbon pollution and the main basic structure of the traditional engines. However, the power of the port fuel injection hydrogen engines is smaller than the same volume gasoline engine because the hydrogen occupies the volume of the cylinder and reduces the air mass flow. The turbocharger can increase the power of hydrogen engines but also increase the NOx emission. Hence, a comprehensive controlling strategy to solve the contradiction of the power, BTE and NOx emission is important to improve the performance of hydrogen engines. This paper shows the controlling strategy for a four-stroke, 2.3L hydrogen engine with a turbocharger. The controlling strategy divides the operating conditions of the hydrogen engine into six parts according to the engine speeds and loads. Solving the main contradiction of the
Luo, Qinghe, Lee, Chia-Fon
Is the “K Value” of an Engine Truly Fuel Independent?2020-01-061504/14/2020
The octane appetite of an engine is frequently characterised by the so-called K value. It is usually assumed that K is dependent only on the thermodynamic conditions in the engine when knock occurs. In this work we test this hypothesis: further analysis was conducted on experimental results from SAE 2019-01-0035 in which a matrix of fuels was tested in a single cylinder engine. The fuels consisted of a relatively small number of components, thereby simplifying the analysis of the chemical kinetic proprieties. Through dividing the original fuel matrix into subsets, it was possible to explore the variation of K value with fuel properties. It was found that K value tends to increase slightly with RON. The explanation for this finding is that higher RON leads to advanced ignition timing (i.e. closer to MBT conditions) and advanced ignition timing results in faster combustion because of the higher pressures and temperatures reached in the thermodynamic trajectory. The Livengood-Wu integral
Cracknell, Roger, Kassai, Masaharu, Shiraishi, Taisuke, Festa, Andrea, Gail, Sandro, Aradi, Allen, Shibuya, Masahiko
Analysis of a Prechamber Ignited HPDI Gas Combustion Concept2020-01-082404/14/2020
High-pressure direct injection (HPDI) of natural gas into the combustion chamber enables a non-premixed combustion regime known from diesel engines. Since knocking combustion cannot occur with this combustion process, an increase in the compression ratio and thus efficiency is possible. Due to the high injection pressures required, this concept is ideally suited to applications where liquefied natural gas (LNG) is available. In marine applications, the bunkering of and operation with LNG is state-of-the-art. Existing HPDI gas combustion concepts typically use a small amount of diesel fuel for ignition, which is injected late in the compression stroke. The diesel fuel ignites due to the high temperature of the cylinder charge. The subsequently injected gas ignites at the diesel flame. The HPDI gas combustion concept presented in this paper is of a monovalent type, meaning that no fuel other than natural gas is used. The high-pressure gas jet is ignited with the aid of flame torches from
Zelenka, Jan, Kammel, Gernot, Wimmer, Andreas, Bärow, Enrico, Huschenbett, Matthias
CO2 Neutral Heavy-Duty Engine Concept with RCCI Combustion Using Seaweed-based Fuels2020-01-080804/14/2020
This paper focusses on the application of bioalcohols (ethanol and butanol) derived from seaweed in Heavy-Duty (HD) Compression Ignition (CI) combustion engines. Seaweed-based fuels do not claim land and are not in competition with the food chain. Currently, the application of high octane bioalcohols is limited to Spark Ignition (SI) engines. The Reactivity Controlled Compression Ignition (RCCI) combustion concept allows the use of these low carbon fuels in CI engines which have higher efficiencies associated with them than SI engines. This contributes to the reduction of tailpipe CO2 emissions as required by (future) legislation and reducing fuel consumption, i.e. Total-Cost-of-Ownership (TCO). Furthermore, it opens the HD transport market for these low carbon bioalcohol fuels from a novel sustainable biomass source. In this paper, both the production of seaweed-based fuels and the application of these fuels in CI engines is discussed. Ethanol and butanol are considered as the most
Seykens, Xander, Bekdemir, Cemil, Han, Jinlin, Willems, Robbert, Van Hal, Jaap
On-Engine Performance Evaluation of a New-Concept Turbocharger Compressor Housing Design2020-01-101204/14/2020
Following market demands for a niche balance between engine performance and legislation requirement, a new-concept compressor scroll has been designed for small to medium size passenger cars. The design adopts a slight deviation from the conventional method, thus resulting in broader surge margin and better efficiency at off-design region. This paper presents the performance evaluation of the new compressor scroll on the cold-flow gas-stand followed by the on-engine testing. The testing program focused on back-to-back comparison with the standard compressor scroll, as well as identifying on-engine operational regime with better brake specific fuel consumption (BSFC) and transient performance. A specially instrumented 1.6L gasoline engine was used for this study. The engine control unit configuration is kept constant in both the compressor testing. The intake and exhaust manifold has been customized to fit the turbochargers and kept identical between the standard and new compressor
Chiong, Meng Soon, Tan, Feng Xian, Rajoo, Srithar, Martinez-Botas, Ricardo F., Yokoyama, Takao, Fujita, Yutaka, Ebisu, Motoki
Analysis of Unburned Hydrocarbon Generated from Wall Under Lean Combustion2020-01-029504/14/2020
The location and cause of unburned HC is analyzed by CFD and LIEF. Under lean combustion, the surface flame quenching occurs over a wide range of walls and large amount of HC is generated. The quenching distance and HC can be organized by laminar combustion speed and boost pressure, those are related to thermal boundary layer thickness.
Sakai, Hiroyuki, Sato, Sei, Mori, Sachio, Nogawa, Shinichiro, Nakatani, Koichiro
Investigation of Diesel-CNG RCCI Combustion at Multiple Engine Operating Conditions2020-01-080104/14/2020
Past experimental studies conducted by the current authors on a 13 liter 16.7:1 compression ratio heavy-duty diesel engine have shown that diesel-Compressed Natural Gas (CNG) Reactivity Controlled Compression Ignition (RCCI) combustion targeting low NOx emissions becomes progressively difficult to control as the engine load is increased. This is mainly due to difficulty in controlling reactivity levels at higher loads. For the current study, CFD investigations were conducted in CONVERGE using the SAGE combustion solver with the application of the Rahimi mechanism. Studies were conducted at a load of 5 bar BMEP to validate the simulation results against RCCI experimental data. In the low load study, it was found that the Rahimi mechanism was not able to predict the RCCI combustion behavior for diesel injection timings advanced beyond 30 degCA bTDC. This poor prediction was found at multiple engine speed and load points. To resolve this, multiple reaction mechanisms were evaluated and a
Dahodwala, Mufaddel, Joshi, Satyum, Koehler, Erik, Franke, Michael, Tomazic, Dean, Naber, Jeffrey
Numerical Investigation of the Combustion Kinetics of Partially Premixed Combustion (PPC) Fueled with Primary Reference Fuel2020-01-055404/14/2020
This work numerically investigates the detailed combustion kinetics of partially premixed combustion (PPC) in a diesel engine under three different premixed ratio fuel conditions. A reduced Primary Reference Fuel (PRF) chemical kinetics mechanism was coupled with CONVERGE-SAGE CFD model to predict PPC combustion under various operating conditions. The experimental results showed that the increase of premixed ratio (PR) fuel resulted in advanced combustion phasing. To provide insight into the effects of PR on ignition delay time and key reaction pathways, a post-process tool was used. The ignition delay time is related to the formation of hydroxyl (OH). Thus, the validated Converge CFD code with the PRF chemistry and the post-process tool was applied to investigate how PR change the formation of OH during the low-to high-temperature reaction transition. The reaction pathway analyses of the formations of OH before ignition time were investigated. It was found that in the case of PR0
Zhao, Yuanyuan, Wang, Hu, Liu, Xinlei, Liu, Daojian, Chenchen, Wang, Zhu, Hongyan, Zheng, Zunqing, Yao, Mingfa
Investigation of Homogeneous Lean SI Combustion in High Load Operating Conditions2020-01-095904/14/2020
Homogeneous lean combustion (HLC) can be utilized to substantially improve spark ignited (SI) internal combustion engine efficiency. Higher efficiency is vital to enable clean, efficient and affordable propulsion for the next generation light duty vehicles. More research is needed to ensure robustness, fuel efficiency/NOx trade-off and utilization of HLC. Utilization can be improved by expanding the HLC operating window to higher engine torque domains which increases impact on real driving. The authors have earlier assessed boosted HLC operation in a downsized two-litre engine, but it was found that HLC operation could not be achieved above 15 bar NMEP due to instability and knocking combustion. The observation led to the conclusion that there exists a lean load limit. Therefore, further experiments have been conducted in a single cylinder research DISI engine to increase understanding of high load lean operation. HLC is known to suppress end-gas autoignition (knock) by decreasing
Clasen, Kristoffer H., Koopmans, Lucien
McLaren: The Engine CompanyR-48503/13/2020
McLaren: The Engine Company is the previously untold story of McLaren Engines, an American company founded in 1969 by Bruce McLaren and his partners to build engines for McLaren's legendary Can-Am and Indy Cars. From this base in suburban Detroit were born the mighty big-block Chevrolet V8s that powered the iconic orange cars to two of their five consecutive Cam-Am championships. McLaren's busy dyno rooms also spawned the howling turbo Offenhausers that put Mark Donohue and Johnny Rutherford in Victory Lane at Indianapolis three times between 1972 and 1976. For decades this non-descript shop was the hotbed of horsepower for factories and top independents alike. McLaren Engines developed the turbocharged Cosworth DFV Formula 1 engine that powered Indy cars for both Team McLaren and Penske Racing. It rendered BMW's turbo engine for U.S. IMSA racing that later became BMW's Formula 1 weapon. The long list of race engines developed here powered Buick Indy and IMSA cars, BMW GTP cars
Meiners, Roger
Study on Multivariable Control for Air and Charging System of Gasoline Engine07-12-02-000602/07/2020
This study explores the multivariable multi-input–multi-output technique based on nonlinear models to decouple actuator interaction and to reduce the calibration workload, as well as to increase control performances, under transient conditions, and also explores the robustness on model uncertainties and system parameter variations. The development of a nonlinear dynamic physical model of air in gasoline engine and its charging system provides the for the control technology. The model uses feedback linearization control to decouple the interaction between actuators and compensate the nonlinearity. A new set of inputs was defined through inversing the differential equation of the system. The relationship between the new inputs and the output is linear and decoupled. In addition, a linear control module is used to ensure transient and steady-state performance as well as closed-loop robustness. The control method has been confirmed on the bench test with a three-cylinder gasoline engine
Wang, Wei, Cai Zhen, Jiang, Liu Shao, Fei
Engineering the world's fastest tractor20TOFHP02_0502/01/2020
JCB worked with design and engineering specialists to build a spectacular speed record-breaker that topped 150 mph. For farmers in a hurry, JCB's Fastrac series agricultural tractors are capable of speeds up to 43 mph (69 km/h) in stock form. But the British company believes in challenging its engineers to improve the breed, and in doing so they've taken the concept of a high-speed ag tractor to new heights. In June 2019, a JCB-modified machine, called Fastrac One, set a new world (modified) tractor speed record, averaging more than 100 mph. Then in November, the JCB engineers, working with counterparts at Ricardo, GKN Wheels & Structures, and Williams Advanced Engineering, raised the record by 32 mph to establish another Guinness World Record: 135.19 mph (217.57 km/h), averaged over two runs at Elvington Airfield in Britain. In one of its passes through the speed trap, the Fastrac Two tractor reached 153.77 mph (247.47 km/h).
Birch, Stuart
High Efficiency by Miller Valve Timing and Stoichiometric Combustion for a Naturally Aspirated Single Cylinder Gas Engine2019-32-058801/24/2020
Small-scale cogeneration units (Pel < 50 kW) frequently use lean mixture and late ignition timing to comply with current NOx emission limits. Future tightened NOx limits might still be met by means of increased dilution, though both indicated and brake efficiency drop due to further retarded combustion phasing and reduced brake power. As an alternative, when changing the combustion process from lean burn to stoichiometric, a three-way-catalyst allows for a significant reduction of NOx emissions. Combustion timing can be advanced, resulting in enhanced heat release and thus increased engine efficiency. Based on this approach, this work presents the development of a stoichiometric combustion process for a small naturally aspirated single cylinder gas engine (Pel = 5.5 kW) originally operated with lean mixture. To ensure low NOx emissions, a three-way-catalyst is used. In order to achieve high engine efficiency, measures implemented include Miller valve timing, optimized intake system
Judith, Jörn, Neher, Denis, Kettner, Maurice, Schwarz, Danny, Klaissle, Markus
Influence of Zn, Mo, P, S-contained Engine Oil Additives on Abnormal Combustion in a Spark Ignition Engine2019-32-058601/24/2020
A Spark Ignition Engine has some kinds of problem to be solved over many years, one of them is abnormal combustion; Low-speed pre-ignition (LSPI) under low-speed, high-load driving conditions for vehicle, and pre-ignition under longterm operation without cleaning a combustion chamber for gas cogeneration. As a cause for abnormal combustion, engine oil droplets diluted by liquid fuel and peeled combustion deposits delivered from engine oil are proposed. In this study, experiments were conducted focusing on engine oil additives having different chemical structure and abnormal combustion behavior. A four-stroke side-valve single cylinder engine that allowed in-cylinder visualization of the combustion flame was used in the experiments. The experimental results showed that the influence of DTC additive on abnormal combustion is small and the zinc component contained in the DTP additives had the effect of advancing the autoignition timing.
Izako, Takuya, Iijima, Akira, Kusumoto, Tatsuya, Utaka, Toshimasa
Rework of an in-line two-cylinder engine for the application in Formula Student2019-32-053201/24/2020
Formula Student is an international design competition, where students all over the world develop, design and build their own race car and afterwards compete with each other at different disciplines at events worldwide. The development process includes every module of the race car and the team of joanneum racing graz has focused on the powertrain since the beginning. The following paper contains an overview of the reworking process of an in-line two-cylinder engine for the application in Formula Student. The intention was to increase the BMEP and at the same time reach a desired power/weight ratio of the engine. The process of selecting the most appropriate turbocharger by means of experimental testing on an engine dynamometer, as well as its optimization by means of numerical simulation, is outlined. Subsequently, the paper discusses the challenges regarding valve timing and finding the best trade-off between power and residual gas with the help of 1D-simulations. The necessary
Feigl B.Sc, Michael, Rößmann B.Sc, Dominik, Michael Trzesniowski, FH-Prof. DI
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