Browse Topic: Marine engines

Items (868)

Exploring the Benefits of Karanja-Oil-Derived Biodiesel-Water Emulsion as a Potential Fuel for Diesel Engines Operated with High-Pressure Fuel Injection Systems

03-17-01-0003

7/21/2023

Abstract Biodiesel is a suitable alternative to diesel because of its carbon neutrality, renewability, lubricity, and lower pollutant emissions. However, extensive research indicates higher oxides of nitrogen (NOx) emissions with biodiesel. A practical method to combat this problem is utilizing water and biodiesel as emulsions. The effect of biodiesel-water emulsion in high-pressure fuel injection systems is not fully explored in the existing literature. The present study addresses this research gap by utilizing biodiesel-water emulsions in a modified light-duty diesel engine. The governor-controlled injection system was adapted to a fully flexible electronic system capable of high-pressure injection. Unlike other literature studies, the fuel injection timings were optimized with biodiesel-water emulsions to maximize brake thermal efficiency (bte) at every load condition. In a novel attempt, the biodiesel source, i.e., raw Karanja oil (RKO), a triglyceride, was utilized as the surfactant to stabilize the biodiesel-water emulsions containing 6%, 12%, and 18% water. The emulsions reduced the ignition delay and cylinder pressures, with less-intense premixed combustion and a more significant diffusion phase combustion than biodiesel. The emulsions also present a delayed combustion phasing following the injection timing trends. Among the tested emulsions, at 5.08 bar brake mean effective pressure (BMEP), 18% biodiesel-water emulsion resulted in an 18% reduced brake specific fuel consumption (bsfc), 5% increase in bte, 30% and 7% mitigation in NOx and smoke levels, with an increase of 10% and 28% for unburned hydrocarbon (HC) and carbon monoxide (CO) emissions.

Gowrishankar, Sudarshan, Krishnasamy, Anand, Aidhen, Indrapal Singh

Impact of Non-Thermal Plasma on Particulate Emissions in Application in a Diesel Engine Exhaust Duct

SAE-PP-001611/26/2021

Particulates and nitrogen oxides comprise the main emission components of the Diesel combustion and therefore are subject to exhaust emission legislation in respective applications. Yet, with ever more stringent emission standards and test-procedures, such as in passenger vehicle applications, resulting exhaust gas after-treatment systems are quite complex and costly. Hence, new technologies for emission control have to be explored. The application of non-thermal plasma (NTP) as a means to perform exhaust gas after-treatment is one such promising technology. In several publications dealing with NTP exhaust gas after-treatment the plasma state was generated via dielectric barrier discharges. Another way to generate a NTP is by a corona high-frequency discharge. Hence, in contrast to earlier publications, the experiments in this publication were conducted on an operated series-production Diesel engine with an industrial pilottype corona ignition system. Originally developed as an alternative for a spark-plug system in SI engines its attributed properties, such as large penetrated volume and high radical concentration, may also be utilized in the exhaust gas stream. To investigate the effects of a corona discharge on Diesel engine emissions, four igniters were integrated in the exhaust duct of a common-rail direct-injection 2.0 liter diesel engine equipped with a diesel particulate filter (DPF). The impact on particulate number, size distribution as well as on nitrogen oxides has been studied for various operational parameters of the corona system. The particulate number was measured downstream of the DPF to observe the level of improvement for remaining unfiltered nanoparticulates. In this first series of tests, a reduction in particulate number of up to 10 % was achieved depending on engine load. Particulate size distribution was then measured upstream of the DPF. In this case, the highest reduction of 10 % was observed in the midrange particulate size of about 60 nm. No increase in other particulate size ranges has been observed.

MobrxivNonAdmin, Lindsay

Impact of Non-Thermal Plasma on Particulate Emissions in Application in a Diesel Engine Exhaust Duct

SAE-PP-001561/25/2021

MobrxivNonAdmin, Lindsay

011 - State-of-Health Online Estimation for Li-Ion Battery

SAE-PP-001231/21/2021

To realize a fast and high-precision online state-of-health (SOH) estimation of lithium-ion (Li-Ion) battery, this article proposes a novel SOH estimation method. This method consists of a new SOH model and parameters identification method based on an improved genetic algorithm (Improved-GA). The new SOH model combines the equivalent circuit model (ECM) and the data-driven model. The advantages lie in keeping the physical meaning of the ECM while improving its dynamic characteristics and accuracy. The improved-GA can effectively avoid falling into a local optimal problem and improve the convergence speed and search accuracy. So the advantages of the SOH estimation method proposed in this article are that it only relies on battery management systems (BMS) monitoring data and removes many assumptions in some other traditional ECM-based SOH estimation methods, so it is closer to the actual needs for electric vehicle (EV). By comparing with the traditional ECM-based SOH estimation method, the algorithm proposed in this article has higher accuracy, fewer identification parameters, and lower computational complexity.

MobrxivNonAdmin, Lindsay

Marine Carburetors and Fuel Injection Throttle Bodies

J1223_202012 (Current)

12/9/2020

This SAE Recommended Practice covers all carburetors and throttle bodies used on permanently installed gasoline marine engines.

Marine Engine Fuel Systems Committee

Test Cell Instrumentation

AIR5026B (Current)10/21/2020

This document discusses, in broad general terms, typical present instrumentation practice for post-overhaul gas turbine engine testing. Production engine testing and engine development work are outside the scope of this document as they will typically use many more channels of instrumentation, and in most cases will have requirements for measurements that are never made in post-overhaul testing, such as fan airflow measurements, or strain measurements on compressor blades. The specifications for each parameter to be measured, in terms of measurement range and measurement accuracy, are established by the engine manufacturers. Each test cell instrument system should meet or exceed those requirements. Furthermore, each instrument system should be recalibrated regularly, to ensure that it is still performing correctly.

EG-1E Gas Turbine Test Facilities and Equipment

Marine Stern Drive and Inboard Spark-Ignition Engine On-Board Diagnostics Implementation Guide

J1939-5_202006 (Current)

6/30/2020

This document describes the application of the SAE J1939 recommended practices for compliance with on-board diagnostic malfunction detection system requirements for marine sterndrive and inboard spark ignition engines, as mandated by the California Air Resources Board (CARB). These Otto-cycle engines are not derived from automotive diesel-cycle engines.

Truck Bus Control and Communications Network Committee

Infrared/Visible Optical Diagnostics of RCCI Combustion with Dieseline in a Compression Ignition Engine

2020-01-05574/14/2020

Compression ignition engines are widely used for transport and energy generation due to their high efficiency and low fuel consumption. To minimize the environmental impact of this technology, the pollutant emissions levels at the exhaust are strictly regulated. To reduce the after-treatment needs, alternative strategies as the low temperature combustion (LTC) concepts are being investigated recently. The reactivity controlled compression ignition (RCCI) uses two fuels (direct- and port- injected) with different reactivity to control the in-cylinder mixture reactivity by adjusting the proportion of both fuels. In spite of the proportion of the port-injected fuel is typically higher than the direct-injected one, the characteristics of the latter play a main role on the combustion process. Use of gasoline for direct injection is attractive to retard the start of combustion and to improve the air-fuel mixing process. In this work, the influence of the direct-injected fuel properties on RCCI combustion mode is studied in an optical compression ignition engine. Gasoline fuel is injected in the intake manifold while a blend of gasoline and diesel (a.k.a. dieseline) is directly injected into the cylinder. Non-conventional optical diagnostics in the visible and infrared spectra are applied for the direct investigation of the in-cylinder phenomena during the injection and the combustion processes. A low-luminosity, mainly kinetically controlled combustion mode has been observed.

Sequino, Luigi, Mancaruso, Ezio, Monsalve-Serrano, Javier, Garcia, Antonio

Optical Characterization of the Combustion Process inside a Large-Bore Dual-Fuel Two-Stroke Marine Engine by Using Multiple High-Speed Cameras

2020-01-07884/14/2020

Dual-fuel engines for marine propulsion are gaining in importance due to operational and environmental benefits. Here the combustion in a dual-fuel marine engine operating on diesel and natural gas, is studied using a multiple high-speed camera arrangement. By recording the natural flame emission from three different directions the flame position inside the engine cylinder can be spatially mapped and tracked in time. Through space carving a rough estimate of the three-dimensional (3D) flame contour can be obtained. From this contour, properties like flame length and height, as well as ignition locations can be extracted. The multi-camera imaging is applied to a dual-fuel marine two-stroke engine, with a bore diameter of 0.5 m and a stroke of 2.2 m. Both liquid and gaseous fuels are directly injected at high pressure, using separate injection systems. Optical access is obtained using borescope inserts, resulting in a minimum disturbance to the cylinder geometry. In this type of engine, with fuel injection from positions at the rim of the cylinder, the flame morphology becomes asymmetric. The optical spatial mapping and tracking method is demonstrated to be well suited for the study of such an asymmetric combustion system. Spatial mapping and tracking of flame position is applied to both engine operating modes; normal diesel operation and dual-fuel operation with diesel pilot ignition of the gas. Similarities and differences between diesel and gas flame shape and development can thus be visualised directly. The effects of changing charge density, gas injection pressure and injection nozzle geometry on the flame geometry and development are also studied.

Hult, Johan, Matamis, Alexios, Baudoin, Eric, Mayer, Stefan, Richter, Mattias

Effect of Split Injection and Intake Air Humidification on Combustion and Emission Characteristics of a Marine Diesel Engine in Partially Premixed Low-Temperature Combustion Mode

2020-01-02984/14/2020

The objective of this study was to investigate combined effects of split injection strategies and intake air humidification on combustion and emissions of a partially premixed charge compression ignition (PCCI) marine diesel engine. In this research, a three-dimensional numerical model was established by a commercial code AVL-Fire to explore in-cylinder combustion process and pollutant formation factors in a four-stoke supercharged intercooled marine diesel engine under partial load at 1350 r/min. The novelty of this study is to combine different water-fuel ratios and fuel injection parameters (pilot injection timing and main injection timing) to find the optimized way to improve engine performance as well as NOx-soot emissions, thus meeting the increasingly stringent emissions restriction. The results indicate that as the main injection timing advances (-14°CA to -20°CA aTDC), the in-cylinder peak pressure increases by about 10%, the main injection ignition delay (MI ignition delay) becomes longer, the CA50 is advanced near the top dead center (TDC), which is effective to improve the indicated thermal efficiency (ITE). Meanwhile, soot emissions are reduced by about 50% compared with the original engine at the -20°CA aTDC main injection timing. The early pilot injection timing can form relatively uniform temperature field and concentration field in the cylinder before the start of main injection (SOMI) timing, which is advantageous to fuel-air mixing. The high level of water-fuel ratio is utilized to reduce overall combustion temperatures and achieve low temperature combustion of the diesel engine. NOx emissions significantly decrease by about 75% compared with the original engine when the water-fuel mass ratio is 2.0. All in all, the technical route to improve the NOx-soot trade-off relationship is found through the coupling optimization of split injection strategies and intake air humidification. Meanwhile, the indicated specific fuel consumption (ISFC) is reduced and NOx-ISFC trade-off relationship is improved.

Cai, Yujie, Wang, Ke, Kong, Shiru, Bian, Zhishang

Effect of Pre-Chamber Enrichment on Lean Burn Pre-Chamber Spark Ignition Combustion Concept with a Narrow-Throat Geometry

2020-01-08254/14/2020

Pre-chamber spark ignition (PCSI) combustion is an emerging lean-burn combustion mode capable of extending the lean operation limit of an engine. The favorable characteristic of short combustion duration at the lean condition of PCSI results in high efficiencies compared to conventional spark ignition combustion. Since the engine operation is typically lean, PCSI can significantly reduce engine-out NOx emissions while maintaining short combustion durations. In this study, experiments were conducted on a heavy-duty engine at lean conditions at mid to low load. Two major studies were performed. In the first study, the total fuel energy input to the engine was fixed while the intake pressure was varied, resulting in varying the global excess air ratio. In the second study, the intake pressure was fixed while the amount of fuel was changed to alter the global excess air ratio. At each global excess air ratio, the fuel injection to the pre-chamber was varied parametrically to assess the effect of pre-chamber enrichment on engine operating characteristics. Multi-chamber heat release analysis was performed to present the pre-chamber and main chamber heat release characteristics separately. The discharge coefficient of the pre-chamber nozzles was determined by the model calibration to match the pre-chamber and main chamber pressure traces in the GT Power software. The analyzed data reveals a two-stage combustion mechanism in the main chamber where the latter stage is thought to be contributing to the bulk ignition of the main chamber charge. The pre-chamber heat release is correlated to the mixture strength of the pre-chamber, which affects the phasing of the pre-chamber combustion and the initial heat release in the main chamber. As the global excess air ratio becomes lean, the combustion efficiency deteriorates with high HC and CO emissions, while NOx emission declines significantly. The resulting heat release data is presented alongside the engine-out specific emissions.

Hlaing, Ponnya, Echeverri Marquez, Manuel, Singh, Eshan, Almatrafi, Fahad, Cenker, Emre, Ben Houidi, Moez, Johansson, Bengt

Multiple Engine Faults Detection Based on Variational Mode Decomposition and Echo State Network

2020-01-04184/14/2020

As a major power source, diesel engines are being widely used in a variety of fields. However, because of complex structure, some faults which cannot be detected by direct signals would occur on engines and even lead to accidents. Among all kinds of indirect signals, vibration signal is the most common choice for faults detection without disassemble because of its convenience and stability. This paper proposed a novel approach for detecting multiple engine faults based on block vibration signals using variational mode decomposition (VMD) and echo state network (ESN). Since the quadratic penalty has a great influence on adaptable VMD that may make expected component signals cannot be extracted exactly, this paper proposed a dynamic quadratic penalty value, which will change with decomposing level. This paper selected a best dynamic quadratic penalty value by analyzing a large amount of data and results showed that this approach can decompose signals more exactly. Based on that, 8 characteristic parameters were extracted to describe faults features comprehensively, while high-dimensional data raised computational difficulty for classifier. To improve the recognition rate of ESN for high-dimensional data, this paper proposed an approach that using dimensionality reduction method, in which the kernel local Fisher discriminant analysis (KLFDA) based on Gauss kernel function was proved to be the best choice, to reduce the dimension of original data firstly. Then the ESN was used to recognize faults by analyzing the low-dimensional data. Results showed that this approach obtained ideal recognition rate and had ability to detect multiple engine faults exactly.

Li, Xin, Bi, Fengrong, Ma, Xiaoqiang, Shen, Pengfei, Cheng, Jiangang

Experimental and Numerical Assessment of Active Pre-chamber Ignition in Heavy Duty Natural Gas Stationary Engine

2020-01-08194/14/2020

Gas engines (fuelled with CNG, LNG or Biogas) for generation of power and heat are, to this date, taking up larger shares of the market with respect to diesel engines. In order to meet the limit imposed by the TA-Luft regulations on stationary engines, lean combustion represents a viable solution for achieving lower emissions as well as efficiency levels comparable with diesel engines. Leaner mixtures however affect the combustion stability as the flame propagation velocity and consequently heat release rate are slowed down. As a strategy to deliver higher ignition energy, an active pre-chamber may be used. This work focuses on assessing the performance of a pre-chamber combustion configuration in a stationary heavy-duty engine for power generation, operating at different loads, air-to-fuel ratios and spark timings. The engine was originally a 6-cylinder compression ignition engine which is here employed as a single cylinder engine and then suitably modified to host the pre-chamber (with its natural gas injection system and spark plug) with a new bowl piston to decrease compression ratio. A 0D model is built to make a thermodynamic analysis to characterize the local conditions in the pre-chamber before spark timing (temperature, pressure and composition), based on a compressible nozzle equation for the mass transfer between the chambers and a simplified Woschni model for the pre-chamber’s heat transfer. A mathematical expression was found to describe the relationship between the local conditions and the early stage of the combustion. Experimental results showed the beneficial effect of spark delay and mixture leaning for the reduction of NOx emissions, while CO, unburned hydrocarbons and engine performance see improvement with lower air-to-fuel ratios and spark advance.

Onofrio, Gessica, Li, Changle, Garcia Valladolid, Pablo, De La Morena, Joaquin, Garcia, Antonio, Tunestal, Per, Beatrice, Carlo

Different Methods to Improve the Exhaust Gas Temperature in Modern Stage V Off-Road Diesel Engine over Transient Emission Cycles

2020-01-09034/14/2020

This paper presents several methods to improve the exhaust gas temperature of a modern diesel engine. A high exhaust gas temperature is needed to improve the after-treatment system efficiency and particulate filter regeneration in low engine loads. This study is based on experimental measurements of two Stage 5 level off-road diesel engines. The effect of the different heating methods determined over steady state runs and emission and performance are presented with standard emission transient test procedure (NRTC). In the first step of the study, an intake air restriction and an exhaust gas restriction method are compared. The intake restriction produces better fuel economy over the measuring cycle. However, with the exhaust restriction, higher exhaust gas temperature can be achieved in low engine loads. In the second phase of study, the intake air restriction method was implemented in the research engine. In addition, active waste gate controlling, and injection retardation methods were taken in use for heating purposes. The engine performance was determined with normal calibration and with high exhaust temperature calibration. The differences to the exhaust temperature, engine performance and emission were presented in transient emission cycle NRTC.

Lauren, Mika, Karhu, Toomas, Niemi, Seppo, Laivola, Miika, Ekman, Jan, Spoof-Tuomi, Kirsi

McLaren: The Engine Company

R-4853/13/2020

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, Cadillac LeMans prototypes, Porsche Trans-Am 944s and David Hobbs' F5000 single seaters. There were McLaren-built big-block turbo V8s for offshore boat racing and even a Cosworth-Vega engine for American dirt tracks! Author Roger Meiners combines his life-long passion for motor racing and technology with his historian's sensibilities to make the engines, cars, and key personalities come alive within this book's pages. Ride along with Meiners as he uncovers little-known details of the company's transition from a race shop to an engineering company, developing lust-worthy performance cars such as the sensational 1987 Buick GNX, the 1989 Pontiac Grand Prix Turbo, the FR500 Ford Mustang concept, and other projects that the public never saw. Today the company, known as McLaren Engineering, is a subsidiary of Canada-based Linamar Corporation, and is sought after by global automakers for its unrivaled testing, development and manufacturing capability.

Meiners, Roger

Devices Providing Backfire Flame Control for Gasoline Engines in Marine Applications

J1928_202002 (Historical)2/25/2020

This SAE Standard covers the minimum requirements for design, construction, and testing of devices to prevent the propagation of backfire flame from within the gasoline engine to the surrounding atmosphere.

Marine Technical Steering Committee

Development of a 3D-CFD Model for a Full Optical High-Pressure Dual-Fuel Engine

03-13-02-00171/27/2020

In times of ever stricter exhaust emission regulations, the importance of alternative combustion processes in internal combustion engines continues to grow. One approach to create a combustion progress which produces low CO2, soot, and methane emissions is the “High-Pressure Dual-Fuel” (HPDF)-combustion. Here, the direct-injected methane is ignited by a small amount of pilot-diesel and burns in a diffusive combustion mode. This study describes the development of a three-dimensional computational fluid dynamics (3D-CFD) model for the HPDF-combustion. A Reynolds-Averaged Navier-Stokes (RANS) approach with k-epsilon modelling for turbulence was chosen for the calculation of the flow field. The pilot fuel injection is implemented by using Lagrangian Particle Methods, whereas the gas injection is a mass flow boundary which is derived from measurements of the injector. The model is validated using data from a fully optically accessible single-cylinder research engine. The flow field is compared with particle image velocimetry (PIV) data taken before the start of injection (SOI). Concerning pilot injection, a grid convergence study is conducted and an optimization is developed to reduce computational costs. The penetration length of the liquid fuel spray is validated against Mie-scattering images which are taken during the “Pilot-Diesel-only” experiments in the fully optical single-cylinder research engine. The ignition and combustion is modeled via detailed chemistry, which is solved using the commercial Software CONVERGE and the SAGE chemistry solver. The flame liftoff length of the pilot-diesel and the ignition and combustion of the underexpanded gas jets are validated using high-speed imaging of flame luminosity and OH* chemiluminescence. It can be shown that the used n-heptane mechanism is capable of correctly reproducing the trends in the ignition and combustion process.

Frankl, Stephanie, Gleis, Stephan

Effects of Sub-Chamber Configuration on Heat Release Rate in a Constant Volume Chamber simulating Lean-burn Natural Gas Engines

2019-32-05511/24/2020

Sub-chamber is a useful device with regard to sustaining stable operation of compressed natural gas (CNG) engines under lean burn conditions. In our previous studies, we applied a sub-chamber injection system to CNG engines, in which a single injector and a spark plug are mounted in a small sub-chamber. The aim of this study is to investigate the effect of the sub-chamber configuration on heat release in the main combustion chamber. 11 types of sub-chamber with different nozzle number, nozzle diameter, and sub-chamber volume were examined under a condition that pressure is 2.3 MPa, and global equivalence ratio is 0.6. When the sub-chamber with smaller nozzles are used, the penetration velocity of burned gas jet increases. In addition, the velocity also increases with an increasing sub-chamber volume. The high-speed penetration of burned gas jet shortens the period of initial flame development. This is because the high-temperature burned gas quickly reaches to side wall of main chamber, and immediately ignites lean mixtures existing in the main chamber. Consequently, combustion duration time until heat release reaches 90 % is also shortened. On the other hand, the velocity difference between the jets from sub-chambers with different nozzle numbers is small. To predict the penetration velocity, we proposed an empirical formula based on the volume, nozzle diameter and nozzle number of sub-chamber. The jet intensity evaluated from the formula shows correlations with duration times of combustion periods as well as penetration velocities of burned gas jets.

Nada, Yuzuru, Kidoguchi, Yoshiyuki, Yamashita, Yuto, Furukawa, Ryo, Kaya, Ryu, Nakano, Hideaki, Kobayashi, Shinichi

The effective use of ethanol for greenhouse gas emissions reduction in a diesel engine

2019-36-01571/13/2020

Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP). Compared to a baseline diesel-only operation, the ethanol-diesel dual-fuel engine yielded up to 57% lower well-to-wheels GHG emissions. Moreover, the dual-fuel combustion strategy attained higher net indicated efficiency than the conventional diesel mode from 0.6 to 2.4 MPa IMEP, with a maximum value of 47.2% at 1.2 MPa IMEP. The analysis also revealed that the use of ethanol resulted in 26% to 90% lower nitrogen oxides (NOx) emissions than the conventional diesel operation. This was attributed to the formation of a more premixed and low temperature combustion process for a dual-fuel operation with an ethanol energy fraction that varied from 56% to 79%. Soot levels from the dual-fuel combustion were maintained comparatively low, with a filter smoke number of less than 0.235. Carbon monoxide and unburned hydrocarbon emissions, however, increased significantly in the dual-fuel combustion. This will likely require the application of a high efficiency oxidation catalyst. Overall, this experimental study demonstrated that a dual-fuel combustion with a low carbon fuel such as ethanol is an effective means of decreasing the dependence on diesel fuel and associated GHG emissions.

Pedrozo, Vinícius, Lanzanova, Thompson, May, Ian, Guan, Wei, Zhao, Hua

Turbocharger Performance Prediction: A Review of Map Modelling

2019-36-01201/13/2020

Supercharging has been increasingly more employed as an approach to improve the internal combustion engine (ICE) thermal efficiency. The turbocharger (TC) stands out as a well-established technology which recovers waste energy from exhaust gases to increase the ICE intake pressure and mass flow rate. Nevertheless, the increasingly stringent restrictions on greenhouse gases emission, concomitantly with performance improvement required from customers, impose a tighter pairing between TC and ICE and higher control of TC operational conditions. Matching a proper TC for a given ICE has a major importance for the global efficiency, having direct impact on specific consumption, emission levels and drivability. This process is typically performed using computational simulations via interpolations of TC tabular performance maps, which details the flow status for given shaft speed and mass flow rate. Although this method provides a reliable and accurate description of the TC performance within the mapped domain, the multiple interpolations and extrapolations required entails high computational costs. Furthermore, the extrapolations required to describe the flow outside the mapped domain are not able to predict well the actual operational condition. To circumvent these issues, alternative modelling approaches have been developed. The current paper provides a comprehensive literature review on current TC modelling strategies proposed by academics and the industry to predict the TC performance with reasonable precision and low computational cost. The review begins with a brief synopsis of TC matching and control presenting requirements and limitations. Subsequently, TC modelling is succinctly presented and its state of art for ICE simulation and control is discussed. Namely, modelling strategies evaluated in this review are physical approaches (meanline models, mean value models and non-dimensional analysis), semiphysical approaches, and black box neural networks models. Lastly, some trends and recommendations for future works are discussed.

Teixeira, José Arthur G. S., Sandoval, Oscar R., Caetano, Bryan Castro, Baeta, José Guilherme Coelho

Improvement of Hybrid Scheme for WAVE-MTAB Model and Analytical Study of Diesel Spray Using Theory on the Spray Similarity

2019-01-232412/19/2019

In order to further improve the thermal efficiency of diesel engines, this report focuses on the influence of injection condition on similarity of similar spray. To accurately reproduce the diesel spray in our laboratory, the WAVE-MTAB model was developed, and improvements were made to switch between two breakup models. As a result, switching of the breakup model can be done according to the physical phenomenon, and it is considered that similar spray can be reproduced generally well when using theory on the spray similarity.

Hosogi, Motoki, Matsumura, Eriko, Senda, Jiro, Hori, Tsukasa

A Study on PCCI Combustion Control in Medium Speed Dual-Fuel Engine

2019-01-217612/19/2019

To achieve simultaneous reduction of CO2 and NOx emission from the Dual-Fuel (DF) engine using natural gas and diesel fuel, Premixed Charge Compression Ignition (PCCI) type combustion is a promising technology. However, to apply this technology to the practical operation of the DF engine, combustion control is key challenge because the ignition of PCCI type combustion is governed by chemical reaction of natural gas/air and diesel fuel premixture and not controlled by direct control parameter such as spark timing of spark-ignition natural gas engine or diesel fuel injection timing of micro-pilot type DF engine. The focus of this study is to understand the effect of engine control parameters on DF-PCCI combustion characteristics to establish the combustion control strategy in medium speed DF engine. Engine experiments using a 4-stroke medium speed single cylinder engine were carried out. Firstly, early two stage diesel pilot injection was applied to realize DF-PCCI combustion. As a result, brake thermal efficiency was successfully improved by 2%pt compared with conventional micro-pilot combustion while achieving low NOx emission to meet the stringent emission standard. THC emission was successfully reduced at the same time. Secondly, the effects of engine control parameters on DF-PCCI combustion characteristics were investigated. Finally, DF-PCCI combustion control strategy in the medium speed engine is discussed and proposed based on the engine test results.

Toshinaga, Kazuteru, Kuribayashi, Masaki

Effect of Alternative Fuels on Marine Engine Performance

2019-01-2230

12/19/2019

Marine transportation sector is highly dependent on fossil-based energy carriers. Decarbonization of shipping can be accomplished by implementing biobunkers into an existing maritime fuel supply chain. However, there are many compatibility issues when blending new biocomponents with their fossil-based counterparts. Thus, it is of high importance to predict the effect of fuel properties on marine engine performance, especially for new fuel blends. In the given work, possible future solutions concentrated on liquid fuels are taken into account. Under consideration are such fuels as biodiesel (FAME), hydrotreated vegetable oil (HVO), straight vegetable oil (SVO), pyrolysis oil, biocrude, and methanol. Knowledge about the behavior of new fuel in an existing engine is notably important for decision makers and fuel producers. Hence, the main goal of the present work is to create a model, which can predict the engine performance from the end-user perspective. For the purpose of modeling, only the latest research on marine fuels is taken into account. In the current approach, results from a representative measurement set-up are compared in order to create a uniform model. As a result, all the provided data are expressed in relative changes in reference to standard marine fuel – heavy fuel oil (HFO). The modeling Is performed by means of multilinear regression and accuracy of the model is relatively high, with a coefficient of determination over 0.9. The outcomes provide a prediction of final engine performance for the specified fuel blend. Knowing the final properties of fuel (such as calorific value, density, viscosity), it is attainable to estimate fuel consumption, carbon dioxide emissions and determine possible fuel compatibility issues. Moreover, the model enables estimation of carbon dioxide (CO2) tailpipe emissions, which should be included in the whole Life Cycle Analysis (LCA) while assessing the renewability index of the fuel.

Wojcieszyk, Michal, Kroyan, Yuri, Larmi, Martti, Kaario, Ossi, Zenger, Kai

Enhancing Peak Firing Pressure Limit for Achieving Better Brake Thermal Efficiency of a Diesel Engine

2019-01-218012/19/2019

An increased cycle expansion ratio is beneficial from a thermodynamic viewpoint to increase the engine efficiency. In this study, the target compression ratio and corresponding thermodynamic cycle layout were investigated by means of a new ideal combustion cycle. To model the experimental pressure traces, the combustion was divided into three parts; constant volume combustion, early expansion combustion and late combustion. This study discussed optimal parameter values for compression ignition combustion under PFP constraints. These parameters included compression ratio, pressure ratios as well as cut-off ratios. Furthermore, this study experimentally investigated the limitation of thermal efficiency and the variation of energy losses under different geometric compression ratios, boosting pressure and degree of constant volume combustion. These experiments utilized a supercharged single-cylinder heavy duty diesel engine with PFP-capability of up to 30 MPa. In conclusion, it is confirmed that improvement in the indicated thermal efficiency and BTE was achieved by increasing the compression ratio. The trade-off between increased compression ratio and higher losses was also established and an optimum compression ratio found.

Enya, Kenji, Uchida, Noboru

Investigation of the High-Pressure-Dual-Fuel (HPDF) combustion process of natural gas on a fully optically accessible research engine

2019-01-217212/19/2019

In the “high-pressure-dual-fuel” (HPDF) combustion process, natural gas is directly injected into the combustion chamber with high pressure at the end of the compression stroke, and burned in a diffusion flame similar to conventional diesel combustion. As natural gas does not self-ignite when injected into hot air, a small amount of diesel fuel is injected directly before the gas injection to provide an ignition source for the gas jets. The HPDF combustion process has the potential to substantially reduce methane slip compared to today’s state of the art premixed lean burn gas engines, and furthermore, phenomena like knocking or misfire can be avoided completely. In this paper, the influences of in-cylinder air density and swirl motion on HPDF combustion is studied via high-speed recordings in a fully optically accessible 4.8 Liter single-cylinder research engine.

Gleis, Stephan, Frankl, Stephanie, Waligorski, Dominik, Prager, Dr.-Ing. Maximilian, Wachtmeister, Prof. Dr.-Ing. Georg

Research of Fuel Characteristic of Dimethyl ether / High Viscosity & Incombustible matter Blend for Marine Diesel Engine

2019-01-222912/19/2019

Diesel engine has fuel combustion capability in various high density oil such as residual fuels or biofuels derived from fossil or living matter. But for commercial use, these fuels except bio diesel fuel (BDF) should be heated, separated and filtered by equipment and dosed or mixed with additive or distillate oil etc. before being supplied to the engine in order to improve combustibility. This study aims to illuminate fuel characteristic of blend contained woody pyrolysis oil (WPO) which is high viscosity and incombustible, and dimethyl ether (DME) whose emission of combustion has no soot particle. This paper describes thermo-physical property of neat WPO and the blend on the basis of the evaluation of fuel fluidity by measurement and calculation of viscosity. According to the result, it was confirmed that the fluidity of WPO was improved by mixing DME and the approximate viscosity expressions at any temperature of WPO and the blend were good accuracy.

MIHARA, Yu, KURO-OKA, Daiki, SHIRAHAMA, Tomoki, KUWAOKA, Kenta, SUZUKI, Takashi, ASANO, Ichiro, DAN, Tomohisa

Experimental study of cylinder oil stripping behavior at the scavenge port of a low-speed two-stroke engine

2019-01-233512/19/2019

The stripping of cylinder oil at the scavenging ports of low-speed two-stroke marine engines is one of the main sources of floating oil droplets existing in cylinders. The combustion of these oil droplets is one of the major reasons of PM emissions and pre-ignition for dual-fuel engines. In order to investigate the stripping behavior, a prototype model and a test bench were set up to carry out the experiment of cylinder oil stripping behavior and single droplet deformation under different conditions. Meanwhile, a CFD model was established to analyze the actual scavenging flow field, and the verification results were obtained: in the case of excessive lubrication, a considerable amount of cylinder oil remains on the upper surface of the scavenge ports. Such cylinder oil can be blown into the cylinder when the ports are opened. Then the oil droplets floating in the cylinder or attaching to the exhaust valve form potential spontaneous combustion points, which leads to the worsening of PM emissions and the threat of pre-ignition, the most harmful abnormal combustion for Otto-cycle dual-fuel engines.

Pan, Min, Feng, Liyan, Gong, Zhen, Yu, Zhengran, Sun, Hongjie, Wang, Zixin, Yan, Peng

A Study of Injection Directions on Improvement of Engine Performance and NOx Emission in A Low-speed Marine Engine

2019-01-232212/19/2019

A computational fluid dynamics (CFD) simulation model for a two-stroke low-speed marine engine has been established in CONVERGE software, to study the impact of different injection directions on fuel consumption and emissions of the engine. The goal of this research was to investigate injection angles in horizontal and vertical directions respectively. According to the simulation results, “trade-off” relationship was found in both directions between fuel consumption and NOx emission. Based on these results, 8° and -16° were considered as optimal injection angles in horizontal and vertical directions. With the optimized injection angles, lower NOx emission can be achieved with a little penalty on fuel consumption.

Sun, Qian, Ji, Wenxia, Huang, Zhen, Zhu*, Lei

Analysis on flow motion and combustion process in pre-chamber and main chamber for low-speed two-stroke dual-fuel engine

2019-01-217512/19/2019

ABSTRACT Low-speed two-stroke dual-fuel engines has been paid more attention due to the energy efficiency design index and Tier III emissions limitations issued by International Marine Organization. Although the dual-fuel engines have strong merits on emissions reduction, which can reach the IMO Tier III without aftertreatment, the power output is much lower than that of diesel engines. Therefore, the dual-fuel engine is also needed to improve continuously. However, the mixing and combustion processes in the engine have not been fully understood. In this study, a 3D-CFD model of the dual-fuel engine was established using CONVERGE to explore the mixing and combustion processes. Locally embedding fine grids are considered at scavenging ports, natural gas injection ports, pre-chamber. The model was validated by experimental in-cylinder pressure. Then, the flow motion, mixing of natural gas and air, flow in pre-chamber, torch and combustion in main-chamber were analyzed based on swirl variation, flow velocity distribution, equivalence ratio distribution and torch propagation.

Liu, Long, Wu, Yue, Xiong, Qian, Liu, Teng

The Investigation of the Structure and Origins of Gasoline Direct Injection (GDI) Deposits.

2019-01-235612/19/2019

The legislative pressures on environmental targets combined with fuel economy requirements have led to the GDI engine enjoying a renaissance. This is because the technology is considered to be the leader in meeting those requirements. However it is also recognized that the engine suffers from injector deposits (ID) and that understanding the formation of and characterization of such deposits is required. This study will deal with the characterization and morphology of injector deposits as well as the fuel constituents leading to such deposits. A number of analytical techniques were used to undertake this such as Scanning Electron microscopy and X-ray Fluorescence (SEM/EDS) mapping with Fourier Transform Infra-red mapping, in conjunction with mass spectrometry studies. Further, work will be described regarding new deposit control additives (DCAs) for GDI which are more effective than traditional DCAs.

Reid, J Barker J, Mulqueen, S, Langley, G J, Wilmot, E M J, Vadodaria, S, Castle, J, Whitaker, J

Effects of Engine Operating Condition and Fuel Property on Pre-Ignition Phenomenon in a Highly Boosted Premixed Natural Gas Engine

2019-01-215412/19/2019

The stochastic pre-ignition phenomenon plays a vital role to limit the further increasing BMEP for natural gas engines. In this study, the pre-ignition propensities were examined in a highly boosted premixed natural gas engine by various engine loads and air/fuel ratios, as well as different methane number (MN) altered by hydrogen addition. A proper pre-ignition evaluation method was proposed referring to intake temperature. Moreover, the limits of in-cylinder temperature and pressure for the onset of pre-ignition were estimated. The results show that both higher IMEP and richer mixture conditions readily lead to pre-ignition. The significant increases of pre-ignition frequency and heavy-knocking pre-ignition cycle present with lowering MN.

Chen, Run, Kuboyama, Tatsuya, Moriyoshi, Yasuo, Yasueda, Shinji, Doyen, Valerie, Martin, Jean-Baptiste

Study of Advanced Control Based on the RBF Neural Network Theory in Diesel Engine Speed Control

03-13-01-000510/14/2019

Abstract Based on radial basis function (RBF) neural network (NN) theory, RBF-Proportional Integral Derivative (PID) diesel engine speed control is proposed. The algorithm has strong self-learning ability and strong adaptive ability, and is able to optimize the control parameters of the speed loop controller in real time. A series of simulations are carried out with different initial weights. Simulation results reveal that initial weights have little effect on RBF-PID control performance. A STM32 MCU-based controller is developed according to the calculation requirement. Experiments are carried out on a D6114 diesel engine generator to verify the proposed speed control algorithm. The simulation results are in agreement with the experimental results. The results show that the influence of initial weights on RBF-PID control algorithm is smaller than that on BP-PID control algorithm. When RBF-PID control algorithm is adopted, the steady speed fluctuation rate is 0.4%. When sudden load is carried out, the speed recovery time is 2.1 s and the instantaneous adjustment rate is 4.93%. When sudden unload simulation is carried out, the speed recovery time is 2.2 s and the instantaneous adjustment rate is 5.27%. Speed control performance of diesel engine has been greatly improved.

Zhao, Guo-Feng, Long, Yun, Ding, Shun-Liang, Yang, Li-Ping, Song, En-Zhe, Ma, Xiu-Zhen

Features of Mathematical Modeling in the Problems of Determining the Power of a Turbocharged Engine According to the Characteristics of the Turbocharger

03-13-01-000110/8/2019

The features of modeling the working process of a turbocharged two stroke marine diesel engine (MDE) in order to reveal the relationship between the engine power and the operation modes of a turbocharger (TC) are discussed in the article. Based on the results of modeling, a model was obtained for the dependence of the power of the MDE on the parameters of the TC operation. As a basic parameter of the TC operation, the TC speed was chosen. The scavenging air temperature is selected as an additional parameter. The article describes the structure of a diagnostic system that allows recording the operating modes of a TC in a noncontact method. The research for vibroacoustic fields of the G70-883kW marine engine was carried out by the author on ship “SEMINOLE,” in the process of research a noncontact vibroacoustic method was used to determine the TC speed. An analysis of the obtained experimental results demonstrates that the use of the averaged model of the dependence of the engine power on the TC speed for one engine family could lead to an error of 5-10%. The article shows that the results of experimental studies to determine the performance of a TC at various modes of operation of a MDE. The use of experimental data in the verification of simulation results has made it possible to reduce the error in determining the power of a MDE by 5-10%. The described method for estimating the power of a MDE based on the TC rotor speed and scavenging air temperature without using expensive piezoelectric type pressure sensors is an alternative method for estimating engine power.

Golovan, Andrii, Gritsuk, Igor, Popeliuk, Vadym, Sherstyuk, Olga, Honcharuk, Iryna, Symonenko, Roman, Saravas, Viktoriya, Volodarets, Mykyta, Ahieiev, Maksym, Pohorletskyi, Dmytro, Khudiakov, Igor

Evaluation of Hybrid Electric Turbocharging for Medium Speed Engines

2019-24-01889/9/2019

This paper investigates the effects of hybrid electric turbocharging on the total system efficiency, the transient loading capability and the operational range of maritime engines, including the effects of the air control valves (cylinder bypass & charge air blow-off valve). An existing and validated mean-value first principle engine model has been adapted to simulate the operating principle of a combustion engine with a hybrid electric turbocharger system. The simulation of power-take-off/in together with an excess air ratio control strategy is included by means of torque addition to/removal from the turbocharger shaft and limiting it with seven boundary controllers. The analysis of the simulation results illustrates a trade-off between the increase of the system efficiency on one side and the transient loading capability of the engine on the other side. With turbocompounding, the system efficiency can be increased at the expense of a deteriorated gas exchange process and increased thermal loading of the engine. And assisting the turbocharger for steady state operation leads to a smaller operating envelope due to the limitation of compressor surge. Combining turbocharger assistance, with either the cylinder bypass or the charge air blow-off valve to avoid compressor surge, results in a rise of the engine torque at a lower speed almost up to a constant engine torque. The system efficiency can be further improved for the low-speed region in case the turbocharger is assisted electrically in combination with the air control valves. The load step capability, parametrized by limiting the minimum excess air ratio during the load step event, proved to be dependent on the timing of the electrical support. It was found, that in order to improve the load step capability, it is necessary to start accelerating the turbocharger a few seconds before the load step occurs. The paper shows the effect of hybrid electric turbochargers on the engine characteristics to facilitate enhanced engine dynamics and improved engine torque at reduced engine speed.

Mestemaker, Benny, Westhoeve, Jan, Visser, Klaas

A Coupled Tabulated Kinetics and Flame Propagation Model for the Simulation of Fumigated Medium Speed Dual-Fuel Engines

2019-24-00989/9/2019

The present work describes the numerical modeling of medium-speed marine engines, operating in a fumigated dual-fuel mode, i.e. with the second fuel injected in the ports. This engine technology allows reducing engine-out emissions while maintaining the engine efficiency and can be fairly easily retrofitted from current diesel engines. The main premixed fuel that is added can be a low-carbon one and can additionally be of a renewable nature, thereby reducing or even completely removing the global warming impact. To fully optimize the operational parameters of such a large marine engine, computational fluid dynamics can be very helpful. Accurately describing the combustion process in such an engine is key, as the prediction of the heat release and the pollutant formation is crucial. Auto-ignition of the diesel fuel needs to be captured, followed by the combustion and flame propagation of the premixed fuel. In this work, an approach based on tabulated kinetics has been used, to include detailed chemistry while still maintaining acceptable computation times. To allow for the modeling of a fumigated dual-fuel engine, this approach has been extended with a Coherent Flame Model (CFM), capable of tracking the premixed flame surface. This methodology has been validated for standard diesel operation, dual-fuel diesel/natural gas and diesel/methanol operation. The model has been applied under a variety of different loads, speeds, diesel substitution ratios and equivalence ratios to capture and study a large operating range. While still observing some discrepancies between certain simulations and the corresponding experiments, already a large improvement in the prediction of fumigated dual-fuel engine operation was observed with the proposed method.

Decan, Gilles, Lucchini, Tommaso, D'Errico, Gianluca, Verhelst, Sebastian

Assessment of Hydrotreated Vegetable Oil (HVO) Applicability as an Alternative Marine Fuel Based on Its Performance and Emissions Characteristics

04-12-02-00075/16/2019

In current study, the combustion and emission characteristics of hydrotreated vegetable oil (HVO) were studied and compared to those of conventional marine gas oil (MGO). The main goal was to verify its applicability as an alternative marine fuel. All experiments were performed using generator set and propeller-law test cycles, i.e., standardized E2 and E3 cycles respectively. Additional emphasis was paid to the particulate matter (PM) emissions combining gravimetric and particle number measurements. The obtained results indicate average 10-15 % reduction in nitrogen oxides (NOx) emissions, while total unburned hydrocarbons (THC) emissions were reduced by 50-55 %. It is believed that a much higher cetane number of HVO together with its superior chemical composition (overall higher H/C ratio, absence of aromatics and heavy-boiling compounds) plays a vital role here. This may also explain the observed around 30 % PM mass reduction, which however showed a strong dependence on load (fuel-air ratio) and speed (time available for combustion) settings. Measured particle size distributions showed a clearly unimodal nature for both the tested fuels with pronounced accumulation (soot) mode found at around 60-80 nm. The total particle concentration in the measured size range of 14-750 nm was almost 30 % higher for HVO than for MGO. This increase is mainly associated with an increase in the number of produced nanoparticles. The main reason for that is most likely the less-optimal injection (shorter penetration length with larger cone angle due to lower density and longer injection duration related to lower volumetric energy content of HVO). The latter negative factors were however counterweighted by the advantages in terms of better chemical composition/structure resulting in an overall better combustion of HVO.

Ushakov, Sergey, Lefebvre, Nicolas

Conceptual Investigations on Full Optical Accessibility to Large-Bore Medium-Speed Engines

03-12-03-00205/15/2019

Optically accessible engines are an essential tool to investigate the combustion process in internal combustion engines via optical and laser optical methods. These methods can be applied to analyze the mixing formation, injection, combustion, and emission formation in situ for a better understanding of the combustion process. The derived findings result in new potentials for increased efficiency and reduced emissions. While the application for passenger car- and truck-size engines is quite common, the application of such an optically accessible engine is rather rare for large-bore engines driving ships or power plants due to their huge scale. The following sections show a conceptual design study to make a large-bore dual-fuel (DF) engine with a bore of 350 mm and stroke of 440 mm fully optically accessible according to the Bowditch principle. As the layout was based on an already existing and working engine of the same principle but half the bore, numerical investigations of the critical parts of the presented large-scale fully optical engine were carried out to consolidate the feasibility of the design study. On the other hand, the study emphasizes the extremely high efforts necessary to build a fully optical engine of this size. Two alternatives to the engine design study of the Bowditch fully optically accessible engine are presented with the advantage of reduced design effort. The first alternative uses a special modified con rod limiting the construction effort of the engine, but the possible observable field of view is quite limited. A second alternative mounts a wide-angle optic in the center of the cylinder head to realize the Bowditch typical horizontal view from the top instead of from the bottom. Comparing these conceptual designs, the wide-angle optic mounted in the cylinder head of alternative 2 presents the most promising approach to build a large-scale fully optically accessible engine with relatively low effort, offering maximum field of view and characteristics comparable to a fully optical engine concerning bearable engine load.

Karmann, Stephan Bernhard, Prager, Maximilian, Wachtmeister, Georg

Emissions from Advanced Ultra-Low-NO _x Heavy-Duty Natural Gas Vehicles

2019-01-07514/2/2019

The emissions of two ultralow NOx heavy-duty (HD) vehicles equipped with 0.02 g/bhp-hr low NOx natural gas (NG) engines were evaluated on a chassis dynamometer. This included a waste hauler and a city transit bus, each with a 0.02 g/bhp-hr NOx L9N near zero (NZ) natural gas engine. The vehicles were tested over a variety of different cycles, including the Urban Dynamometer Driving Schedule (UDDS), port drayage cycles, transit bus cycles, and a refuse truck cycle. For both vehicles, the NOx emissions results were below the 0.02 g/bhp-hr level for most cycles, with the exception of some cold start tests. For the waste hauler, NOx emissions averaged between 0.014 and 0.002 g/bhp-hr for the hot start tests, and from 0.043 to 0.014 g/bhp-hr for the cold start tests. This represented NOx emissions reductions from 97%-100% of compared with previous ISL G 8.9 engines. For the transit bus, the NOx emissions ranged from 0.0007 g/bhp-hr to 0.0042 g/bhp-hr for the warm tests and up to 0.04 g/bhp-hr for the cold start tests. The NOx results for the warm tests are 99% lower than the existing 2010 NOx diesel standard (0.2 g/bhp-hr) and 90% lower than the optional low NOx standard (0.02 g/bhp-h). In contrast, some elevation of ammonia emissions was observed for both vehicles, due to reactions that occur over the three way catalyst. Overall, the results suggest that ultralow NOx NG engines could play an important role in reducing NOx emissions from heavy-duty vehicles towards near zero levels in urban areas. The particle mass emissions were low and typically were more than 90% lower than the 2010 certification standard (10 mg/bhp-hr) for the L9N engine for both applications. Particle number (PN) emissions for the L9N (0.02 g/bhp-h) and other previous tests of ISL G 8.9 (0.2 g/bhp-h) engines both show higher PN emissions compared to diesel vehicles equipped with diesel particle filters (DPFs). Fuel economy, greenhouse gas and nitrous oxide (N2O) emissions are also reported in this paper.

Li, Chengguo, Han, Yuwei, Jiang, Yu, Yang, Jiacheng, Karavalakis, George, Durbin, Thomas D., Johnson, Kent

Computational Optimization of Pressure Wave Reflection on the Piston Surface for Single Point Autoignition Gasoline Engine with Colliding Pulsed Supermulti-Jets Leading to Noiseless-High Compression and Nearly-Complete Air-Insulation

2019-01-02354/2/2019

A new engine concept based on pulsed supermulti-jets colliding at a small area around the chamber center was proposed in our previous research. It was expected to provide noiseless high compression ratio and nearly-complete air-insulation on chamber walls, leading to high thermal efficiency. In the previous reports, three-dimensional computations for the unsteady compressible Navier-Stokes equation were conducted, which were qualitative because of using regular grid method. This time, we develop a new numerical code in order to quantitatively simulate the compression level caused by the jets colliding with pulse. It is achieved by applying a staggered grid method to improve conservatibity of physical quantities at very high compression in combustion phenomena. Computations at a simple condition were fairly agreed with a theoretical value. Computational results obtained for a complex geometry of an engine by the new code had less error than one with previous codes. In addition, the results led us to an idea of new disposition of nozzles to achieve higher compression ratio. Furthermore, we tried to optimize the effect of pressure wave reflection on the piston surface by changing the movement of piston in order to achieve higher compression ratio leading to lower exhaust energy.

Hosoi, Aya, Konagaya, Remi, Kawaguchi, Sota, Sogabe, Yasuhiro, Yamashita, Yuya, Naitoh, Ken

An Exploratory Look at an Aggressive Miller Cycle for High BMEP Heavy-Duty Diesel Engines

2019-01-02314/2/2019

Through aggressive application of the Miller Cycle, using two-stage turbocharging, medium speed diesel marine and stationary power engines are demonstrating over 30 bar rated power BMEP, and over 50 percent brake thermal efficiency. The objective of this work was to use engine cycle simulation to assess the degree to which the aggressive application of the Miller Cycle could be scaled to displacements and speeds more typical of medium and heavy truck engines. A 9.2 liter six-cylinder diesel engine was modeled. Without increasing the peak cylinder pressure, improved efficiency and increased BMEP was demonstrated. The level of improvement was highly dependent on turbocharger efficiency - perhaps the most difficult parameter to scale from the larger engines. At 1600 rpm, and a combined turbocharger efficiency of 61 percent, the baseline BMEP of 24 bar was increased to over 26 bar, with a two percent fuel consumption improvement. As turbocharger combined efficiency increased, to over 75 percent as seen in large, medium speed engines, over 29 bar BMEP was achieved, with over six percent fuel consumption improvement. Similar results were seen at 1200 rpm, with a maximum BMEP of over 34 bar, and greater than two percent fuel consumption improvement, at a turbocharger combined efficiency of 61 percent. Application considerations including speed and load range, and emission constraints are discussed.

Hoag, Kevin L.

Investigating Effects of Different Influence Factors on the Dynamic Response of a Common-Rail Injector

2019-01-02724/2/2019

The electrical control common-rail injector (CRI) is a key component in marine diesel engines. Herein, a detailed fluid-mechanical-electric-magnetic coupling mathematic model regarding the CRI was established, considering the transient of fuel properties, different structure parameters of the CRI, and the nonlinear magnetization and magnetic saturation of magnetic materials of the high-speed solenoid valve (HSV) for the CRI. This model was verified by comparing the calculated injection rate with the experimental data at different injection pressures, and the good consistencies obtained proved the validity of this model. Based on this model, the effect of different factors on the dynamic response of the injector was investigated to prepare for the optimization. The results demonstrated the different structure parameters of the injector, such as the diameters of the inflowing control orifice (OZ) and outflowing control orifice (OA), maximum needle displacement, diameter of the control plunger, and driving strategy, influenced the dynamic response of the CRI with varying degrees. For the open response, the influence degree from high to low is the diameter of the control plunger, OA, OZ, maximum needle displacement, and boost voltage; for the close response, it is the control plunger, OZ, maximum needle displacement, and hold current. The influence degree of the structure parameters is always stronger than the driving strategy. Establishing a detailed mathematic model is helpful to study the influence of different factors, and an effective optimum design for an injector and its HSV is proposed in detail.

Zhao, Jianhui, Yue, Pengfei, Wei, Kebiao, Grekhov, Leonid

Advances in Partial Oxidation of Palm Oil Based Biodiesel Reforming to Hydrogen Production for Diesel Engine Applications

2019-01-14123/25/2019

The aims of this research is investigate the hydrogen production via biodiesel fuel partial oxidation reforming. Hydrogen production can enhance combustion in cylinder and improved aftertreatment activities. A reforming reaction is when a chemical reacts with oxygen available in exhaust gas and diesel fuel injection. The 2%Pt-1%Rh-CeO2-ZrO2/γ-Al2O3 was selected as the active catalyst in this research. This study investigates the effect of gas space velocity (SV) (e.g., 10k h-1 and 16k h-1) and fuel addition flow rate (10-30 ml/h) on hydrogen production efficiency. As can be seen that the hydrogen from reforming reaction was promoted under the real engine operating conditions. Hydrogen is produced via partial oxidation of hydrocarbons reforming. The effects of space velocity SV (h−1) and hydrocarbon addition, which enhanced energy input for the reforming process, are the main effect on hydrogen production over the reforming catalyst. The maximum hydrogen yield are achieved 11%. In the future, hydrogen production via partial oxidation fuel reforming could be developed for production of hydrogen on-board the vehicle.

Theinnoi, Kampanart, Sawatmongkhon, Boonlue, Temwutthikun, Warirat, Wongchang, Thawatchai

Hose and Hose Assemblies for Marine Applications

J1942_201903 (Current)3/22/2019

SAE J1942, developed through the cooperative efforts of the U.S. Coast Guard and SAE, became effective August 28, 19911, as the official document for nonmetallic flexible hose assemblies for commercial marine use. This SAE Standard covers specific requirements for several styles of hose and/or hose assemblies in systems aboard commercial vessels inspected and certificated by the U.S. Coast Guard. It is intended that this document establish hose constructions and performance levels that are essential to safe operations in the marine environment. Refer to SAE J1273 for selection, installation, and maintenance of hose and hose assemblies. Refer to SAE J1527 for hose to convey gasoline or diesel fuel aboard small craft, including pleasure craft and related small commercial craft regulated directly or by reference under 33 CFR 183 Subpart J, and boats and yachts meeting American Boat and Yacht Council standards. SAE J1942-1 is a listing of the products which have been certified for use in the applications described in SAE J1942, Table 1, for fluid power, fuel oil, lube oil, water, and pneumatic systems. SAE J1942-1 is updated yearly and is available from SAE as a single copy document.

Hydraulic Hose and Hose Fittings Committee

Influence of the Backpressure on Urea Sprays Generated by an Air-Blast Atomizer for Large-Scale SCR-Applications

2019-01-00461/15/2019

In 2016, the latest step of emission standards for marine ships came into operation. As the emission limit for nitric oxides has decreased to approximately 25% of the former values, selective catalytic reduction (SCR) will play an important role to fulfil those limits. SCR is an established method in the field of trucks and heavy diesel cars, but applying it to ships requires further research and development. The demands on ship engines are different, not only due to the large scales but also because the engineering process is strongly based on numerical simulations. To allow the validation of simulations at well-defined conditions and to investigate the fundamental processes, e.g. of the injection of urea solution for marine applications, a high pressure hot gas test rig was built up at the ITV. The current work focuses on the injection of urea solution by an air-blast atomizer. The spray breakup is the initial part of the urea decomposition, which is why reliable validation data is needed for modelling and simulating the respective spray and chemical processes. Therefore, the role of the atomization air flow rate in combination with different hot gas pressures was studied. The pressure influence is of particular interest, due to the possibility to install an SCR-system upstream the turbocharger of a marine engine. High speed shadowgraphy was applied to investigate the primary breakup of the urea spray. The breakup phenomena are discussed and combined with droplet spectra, which were measured by phase-Doppler anemometry (PDA). Apart from obtaining validation data, the study gives answers to the guiding question how to obtain acceptably fine sprays by using minimal atomization air under various circumstances.

Höltermann, Markus, Wichmar, Jan, Dinkelacker, Friedrich

NOx Model Calibration for BS VI Applications

2019-26-00501/9/2019

Challenging limits for NOx in BS VI emission legislation demand high performance conversion techniques. Exhaust after treatment systems such as Lean NOx Trap and selective catalytic reduction can provide effective reduction of Engine out NOx emissions. From the moment of engine start, these systems require reliable signal input of the NOx sensor. The efficient use of such DeNOx systems demands earliest possible activation of the upstream NOx sensor. However, attainment of the sensor dew point delays reliable measurements. Data collected from the emission test cycles, WLTC and NEDC indicates the unavailability of NOx sensor from the beginning of the test cycle. Hence, requirement of a NOx model is inevitable to estimate NOx emissions till sensor reaches its dew point. The scope of this paper is to elucidate the calibration process through which a robust estimation of the NOx emissions can be made in different engine modes along with varying ambient conditions. The NOx model is capable of estimating the real time NOx emission using a map based approach taking in to account multiple factors such as coolant temperature, ambient air temperature and pressure. Initially, a set of reference maps is generated for the required engine modes by performing mappings at the dynamometer. With state of the art climatic dynamometers, calibration tools and techniques, it is possible to introduce a robust calibration of the model which the De NOx system can rely upon. This paper contains data collected from measurements at emission, non-emission dynamometers, cold and hot temperature test trips, altitude test trips. The validated NOx model presented in this paper is able to predict real time NOx emission with a deviation of less than 5%.

Kulkarni, Chinmay Vivek, Rathod, Devising, Sharma, Vijay

Dynamic Response Evaluation of a Chassis of a Generator Set Using FEA techniques

2019-26-01981/9/2019

A Generator set is comprised of mainly an Engine, Alternator and Chassis. High Horse-Power Generator development is challenging, with lots of complexities in physical and virtual validations. Creating high fidelity analytical model is always beneficial and economical at the design stages as it avoids repetitive tests on various design concepts. This paper reports analytical methods of developing an FEA model of a Generator for locomotive application and its correlation with Test. Highlighted as well are some of the challenges faced in FE modeling of a large Generator model (60 liters engine capacity) with node count of around 4 million. In this technique, Modal Analysis is first performed to capture the dynamic behavior. More than 95 % correlation is achieved between the FEA and test natural frequencies (Bending modes). Harmonic Analysis with Modal Superposition is then applied to understand the dynamic response of a Chassis under the action of engine vibratory loads. In this paper commercial FEA software Ansys was used for evaluating chassis dynamic response using Modal and Harmonic analysis techniques. Engine Cylinder forces like Piston axial, Side forces and the Main bearing vertical and lateral forces are used as excitation forces in FEA model. Experimental Modal Analysis (Cold Engine) and Steady State Operating test (Hot/Running Condition) were used as physical validations using LMS Test.Lab. Despite limited availability of some input information, this method has shown encouraging correlation up to 90% when correlated with operating deflection shapes on a running Generator set data for lower order harmonics. Chassis design life is also validated for infinite vibratory load cycles using FE-Safe.

Gadwal, Muzammil Mohammed Gaffar, Cheah, Sze Kwan, Fapal, Anand, Patwardhan, Mahesh Anand

Low-Temperature Coolant Circuit Nomenclature and Applications

J3136_201811 (Current)

11/8/2018

The document provides clarity related to multiple temperature coolant circuits used in on- and off-highway, gasoline, and light- to heavy-duty diesel engine cooling systems. Out of scope are the terms and definitions of thermal flow control valves used in either low- or high-temperature coolant circuits. This subject is covered in SAE J3142.

Cooling Systems Standards Committee

Cognitive Model of the Internal Combustion Engine

2018-01-17389/10/2018

This paper describes research focused upon improved the quality of automobile engine quality. Methods and models were developed for estimating and predicting the technical condition of internal combustion engine (ICE), which provides usage of the decision support making in the search for minimum fuel consumption regimes. We developed models of multi-criterion, multiparametric optimization of energy and material-material characteristics of ICE according to the system approach. The developed methods and models for estimating and predicting the technical state of the functionally interconnected and interacting ICE components are performed taking into account their hierarchy and topologies, energy resource used and the fuel. The cognitive methodology has been used to make engine models researches and analysis. The paper focuses on the fuzzy logic approach applying, considering the indeterminacy, incompleteness and unclear information in the engines operation processes. Cognitive, imitation and fuzzy models for estimating and predicting the technical state of ICE have been developed by the authors of this paper, which allowed to identify ICE’s most vulnerable components, set weight values, influence on fuel consumption according to the quantitative and qualitative energy interchange between ICE components. The received results provide quality enlargement of the ICE operation and their functional components, based on the developed estimation and prediction methods of their technical condition. The paper describes results the cross-platform software application which was implemented using the high-level Java programming language and XML markup language. Developed software allows us to provide user’s flexible interaction process with the module of the decision support system, which is based on implementation of the developed methods and models for the ICE technical condition estimating and predicting. Usage of the developed software helped to obtain optimization results of the energy and material characteristics of the explored ICE, which allows us to find several Pareto-optimal solutions for quality criteria that affect fuel consumption for each single model. This has led to a reduction of components wear, which leads to reducing fuel consumption during ICE operation.

Vychuzhanin, Vladimir, Rudnichenko, Nickolay, Shybaiev, Denys, Gritsuk, Igor, Boyko, Victor, Shybaieva, Natalia, Golovan, Andrii, Zaharchuk, Victor, Rabinovich, Ernest, Savchuk, Volodymyr, Zenkin E.Y., Evgeny

Design Parameters for Small Engines Based on Market Research

2018-01-17179/10/2018

Small internal combustion engines outperform batteries and fuel cells in regards to weight for a range of applications, including consumer products, marine vehicles, small manned ground vehicles, unmanned vehicles, and generators. The power ranges for these applications are typically between 1 kW and 10 kW. There are numerous technical challenges associated with engines producing power in this range resulting in low power density and high specific fuel consumption. As such, there is a large range of engine design solutions that are commercially available in this power range to overcome these technical challenges. A market survey was conducted of commercially available engines with power outputs less than 10 kW. The subsequent analysis highlights the trade-offs between power output, engine weight, and specific fuel consumption. These engines are analyzed to show the benefits and disadvantages of different engine design parameters including fuel type, number of strokes per cycle, number of cylinders, intake pressure, and cooling strategy. A Pareto frontier analysis is conducted to identify the top performing engines based on the output power and the total power system weight. Recommended designs are presented for different ranges of output powers.

Mittal, Vikram

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