Browse Topic: Compound engines

Items (143)
Find
Investigations on Supercharging and Turbo-Compounding of a Single Cylinder Diesel Engine2022-01-051203/29/2022
Despite the advantages of turbocharging in improved engine performance and reduced exhaust emissions, single-cylinder engines remain naturally aspirated (NA) and are not generally turbocharged. This is due to the shortcomings with pulsated and intermittent exhaust gas flow into the turbine and the phase lag between the intake and exhaust stroke. In the present study, experimental investigations are initially carried out with a suitable turbocharger closely coupled to a single-cylinder diesel engine. Results indicated that the engine power dropped significantly by 40% for the turbocharged engine compared to the NA version even though the mass flow rate of air was increased by 1.4 times with turbocharging. A novel approach of decoupling the turbine and the compressor and coupling them separately to the engine is proposed to address these limitations. Also, an impulse turbine is chosen for this application, better suited to extract energy during the pulsated exhaust flow. Commercially
Ramkumar, J, Krishnasamy, Anand, Ramesh, A
Technical Paper
Modelling Transient Control of a Turbogenerator on a Drive Cycle2022-01-049503/29/2022
GTDI engines are becoming more efficient, whether individually or part of a HEV (Hybrid Electric Vehicle) powertrain. For the latter, this efficiency manifests itself as increase in zero emissions vehicle mileage. An ideal device for energy recovery is a turbogenerator (TG), and, when placed downstream the conventional turbine it has minimal impact on catalyst light-off and can be used as a bolt-on aftermarket device. A Ricardo WAVE model of a representative GTDI engine was adapted to include a TG (Turbogenerator) and TBV (Turbine Bypass Valve) with the TG in a mechanical turbocompounding configuration, calibrated using steady state mapping data. This was integrated into a co-simulation environment with a SISO (Single-Input, Single-Output) dynamic controller developed in SIMULINK for the actuator control (with BMEP, manifold air pressure and TG pressure ratio as the controlled variables). Transient verification with WAVE-RT was conducted on WLTP and NEDC drive cycles, estimating
Petrovich, Simon, Ebrahimi, Kambiz, Mason, Byron, Watson, Andrew
Technical Paper
An Experimental Study of a Waste Heat Recovery System Connected to a Diesel-Gen-Set2017-01-012303/28/2017
In general, diesel engines have an efficiency of about 35% and hence, a considerable amount of energy is expelled to the ambient air. In water-cooled engines, about 25%, 33% and 7% of the input energy are wasted in the coolant, exhaust gas, and friction, respectively. The heat from the exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Studies related to the application of recoverable heat to produce additional power in medium capacity diesel engines (< 100 kW) using separate Rankine cycle are scarce. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. For this type of application, the heat exchangers are needed to be designed in such a way that it can handle the heat load with reasonable size, weight and pressure drop. This paper describes the study of a diesel generator-set attached with an exhaust heat recovery system. Superheated steam was produced by using two heat
Bari, Saiful
Technical Paper
Application of Rankine Cycle to Passenger Vehicle Waste Heat Recovery - A Review2016-01-017804/05/2016
Rankine cycle (RC) is a thermodynamic cycle that converts thermal energy into mechanical work, which is commonly found in thermal power generation plants. Recently, there are many studies focusing on applying Rankine cycle to recover low-grade waste heat. On-road vehicles, which convert around one third of the fuel energy into useful mechanical energy for propulsion, are moving energy conversion systems that generate considerable waste heat. It was found from many research studies that Rankine cycle has a great potential to be applied to harvest waste heat from automobiles. However, different from other low-grade waste heat sources, vehicles have limited space for the RC system integration and the waste heat is relatively unstable. In the current paper, the efforts in the past few decades related to applying RC to on-road vehicles, specifically passenger cars, are reviewed. Characteristics of the waste heat sources on vehicles and the constraints put on the automotive RC application
Zhou, Feng, Dede, Ercan, Joshi, Shailesh
Journal Article
Investigation of Engine Processes with Extreme Pressures and Turbocompounding2016-01-056704/05/2016
This work is based on calculations about extreme mean effective and maximum pressures which were published earlier by the author and colleagues. The motivation for the work presented in this paper is to reduce the maximum pressure while keeping a high mep without sacrificing efficiency. It is investigated in a theoretical study in how far this can be accomplished via turbocompounding. The basis is a 320 mm bore four stroke medium speed engine. It is equipped with a state-of-the-art two stage turbocharging system. As a first step turbocompounding is investigated for mean effective pressures from 22 to 80 bar. The bsfc of the turbocharged engine is in the range of 175 to 185 g/kWh depending on mep. With turbocompounding the exhaust pressure before turbine is optimised and figures between 160 and 165 g/kWh are reached. Thermal loading of the engine increases. In the second step strategies to reduce maximum pressure are investigated for an mep of ca. 50 bar. Reduced compression ratio and
Eilts, Peter
Technical Paper
On Handling Waste Heat from Waste Heat Recovery Systems in Heavy-Duty Vehicles2015-01-279209/29/2015
The automotive industry have become more and more interested in recovering waste heat from internal combustion engines, especially with future, tighter fuel and CO2 emission regulations in sight. In this study, we consider an automotive Rankine Waste Heat Recovery System on a long-haulage truck. This system transforms some of the combustion engine's waste heat into useful energy, but it still needs to return remaining heat to the surrounding, either through a direct condenser or from an indirect condenser via a Low Temperature Radiator, and this in the regular cooling module of the vehicle. We focus on the integration of WHR-dedicated LTR or condenser into a generic, conventional truck-cooling module with an AC condenser, a cross-flow Charge Air Cooler, a down-flow High Temperature Radiator, and a fan. WHR cooling concepts considered are an indirect system with LTR; either in front or back of CAC, a direct system with condenser either in front or back of CAC. In addition, there is a
Erlandsson, Olof, Skare, Thomas, Contet, Arnaud
Technical Paper
Organic Rankine Cycles with Dry Fluids for Small Engine Exhaust Waste Heat Recovery2013-01-087804/08/2013
Engine manufacturers are considering the implementation of thermodynamic cycles for Waste Heat Recovery (WHR) in order to increase Internal Combustion Engine (ICE) system thermal efficiency. For these secondary cycles, the literature illustrates the preference of Organic Rankine Cycles (ORC's) due to its simplicity and efficient recovery of the medium grade waste heat found in engine exhaust. This paper simulates the heat recovery capacity of eight dry fluids (butane, pentane, hexane, cyclopentane, benzene, toluene, R245fa, and R123) for an ORC based on the exhaust from a single-cylinder diesel engine-generator operating under five different loading conditions. The model, developed using REFPROP and the Matlab Optimization Toolbox, represents the physical components using isentropic pump and expander efficiencies, along with two-zone heat exchangers. All fluids present cycle efficiencies between 10-15%, with the heaviest hydrocarbons generating the largest amount of work. Of these
Sprouse III, Charles, Depcik, Christopher
Journal Article
Review of Rankine Cycle Systems Components for Hybrid Engines Waste Heat Recovery2012-01-194209/24/2012
In any internal combustion engine, the amount of heat rejected from the engine, and associated systems, is a result of the engine inefficiency. Successfully recovering a small proportion of this energy would therefore substantially improve the fuel economy. The Rankine Cycle system has been raising interest for its aptitude to produce systems capable of capturing part of this waste heat and regenerate it as electrical or mechanical power. By integrating these systems into existing hybrid engine environments, it has been proved that Rankine Cycle system, which is more than 150 years old, can play a major role in reducing fuel consumption. The use of such a system for waste heat recovery on a hybrid engine represents a promising compromise in transforming the thermal energy into electricity and feeding this electricity back to the vehicle drivetrain by using the in situ electrical motor system or storing it into batteries. With this aim in mind, a comprehensive background study on the
Lopes, Jose, Douglas, Roy, McCullough, Geoffrey, O'Shaughnessy, Richard, Hanna, Alister, Rouaud, Cedric, Seaman, Rachel
Technical Paper
Engine Terminology and Nomenclature - GeneralJ604_201108 (Current)08/05/2011
This SAE Recommended Practice is applicable to all types of reciprocating engines including two-stroke cycle and free piston engines, and was prepared to facilitate clear understanding and promote uniformity in nomenclature. Modifying adjectives in some cases were omitted for simplicity. However, it is good practice to use adjectives when they add to clarity and understanding.
SAE IC Powertrain Steering Committee
Recommended Practice
Waste Heat Recovery Concept to Reduce Fuel Consumption and Heat Rejection from a Diesel Engine2010-01-192810/05/2010
Fuel economy is critical for heavy-duty line haul applications. As fuel prices rise and impending fuel economy regulations are implemented, new ways to improve heavy-vehicle fuel economy will be in high demand. AVL Powertrain Engineering has undertaken a research and development project to demonstrate the feasibility of a Rankine Cycle Waste Heat Recovery (WHR) system. The goals of the project were to reduce the overall engine heat rejection, specific emissions and fuel consumption (CO₂ emissions) of heavy-duty diesel engines by converting heat that is typically wasted to the exhaust stack and through the EGR cooler to useable mechanical energy. A detailed thermodynamic analysis was conducted which laid the groundwork for working fluid selection and proper sizing of the WHR components. Based on the system specifications, a prototype WHR system was designed and built. The performance of the system was evaluated on a 10.8-liter heavy-duty on-highway diesel engine.
Teng, Ho
Journal Article
Improving Fuel Economy for HD Diesel Engines with WHR Rankine Cycle Driven by EGR Cooler Heat Rejection2009-01-291310/06/2009
The fuel saving benefit is analyzed for a class-8 truck diesel engine equipped with a WHR system, which recovers the waste heat from the EGR. With this EGR-WHR system, the composite fuel savings over the ESC 13-mode test is up to 5%. The fuel economy benefit can be further improved if the charge air cooling is also integrated in the Rankine cycle loop. The influence of working fluid properties on the WHR efficiency is studied by operating the Rankine cycle with two different working fluids, R245fa and ethanol. The two working fluids are compared in the temperature-entropy and enthalpy-entropy diagrams for both subcritical and supercritical cycles. For R245fa, the subcritical cycle shows advantages over the supercritical cycle. For ethanol, the supercritical cycle has better performance than the subcritical cycle. The comparison indicates that ethanol can be an alternative for R245fa.
Teng, Ho, Regner, Gerhard
Technical Paper
EFFECT OF INJECTION PRESSURE AND INJECTION TIMING ON A SEMI-ADIABATIC CI ENGINE FUELED WITH BLENDS OF JATROPHA OIL METHYL ESTERS2008-28-007001/09/2008
A naturally aspirated four stroke single cylinder CI engine was modified to run as semi-adiabatic CI engine. The effect of different injection pressure and injection timing of a standard and semi-adiabatic engine on the combustion performance and emission characteristics of jatropha oil methyl ester (JOME) and its volume blends with diesel is presented in this paper. Performance of the CI engine was evaluated in terms of brake specific energy consumption, brake thermal efficiency, exhaust gas temperature and exhaust gas composition. Five different volume blends of JOME viz. B5, B10, B15, B20 and B25 was used for the combustion studies at various injection pressures viz. 180, 200, 220 and 240 bar and also at different injection timings i.e. 22°,27° and 32° btdc. This experimental study focused on deriving an optimal injection timing and pressure for the satisfactory operation of JOME blends in a semi-adiabatic engine. The study revealed that acceptable brake thermal efficiency, brake
Dhananjaya, D A, Mohanan, P, Sudhir, C V
Technical Paper
Waste Heat Recovery of Heavy-Duty Diesel Engines by Organic Rankine Cycle Part II: Working Fluids for WHR-ORC2007-01-054304/16/2007
In Part I of this paper, the organic Rankine cycle for waste heat recovery (ORC-WHR) from the heavy-duty diesel truck engines was discussed. This work is Part II of the paper. The efficiency of the ORC-WHR system varies considerably with thermodynamic properties of the working fluid. In this work, characteristics of candidate working fluids are discussed on the basis of the thermodynamic theory. The discussion covers inorganic and organic fluids for both pure fluids and binary-mixture fluids. On the basis of the characteristics of the working fluids, the thermal efficiency for the ORC-WHR system is analyzed. Discussions and conclusions of this paper are helpful in selecting proper working fluids for the ORC-WHR system and determining a proper temperature range for system operations.
Teng, Ho, Regner, Gerhard, Cowland, Chris
Technical Paper
Waste Heat Recovery of Heavy-Duty Diesel Engines by Organic Rankine Cycle Part I: Hybrid Energy System of Diesel and Rankine Engines2007-01-053704/16/2007
Waste heat from a heavy-duty truck diesel engine is analyzed employing the first and second law of thermodynamics. A hybrid energy system is proposed, with the diesel cycle being hybridized with an organic Rankine cycle for waste heat recovery (ORC-WHR). The charge air cooler and EGR cooler(s) are integrated in the ORC loop as pre-heaters and the ORC working fluid serves as the coolant for these coolers. A supercritical reciprocating Rankine engine is proposed, which avoids using the high-cost evaporator and is easier for the system packaging. It is demonstrated in a case study that up to 20 % of waste heat from the heavy-duty diesel engine may be recovered by the supercritical ORC-WHR system, making the efficiency for the hybrid energy system be ≥ 50%. Discussion on working fluids for the WHR-ORC system is covered in Part II of this paper.
Teng, Ho, Regner, Gerhard, Cowland, Chris
Technical Paper
Achieving High Engine Efficiency for Heavy-Duty Diesel Engines by Waste Heat Recovery Using Supercritical Organic-Fluid Rankine Cycle2006-01-352210/31/2006
A supercritical organic Rankine cycle (ORC) system for recovery of waste heat from heavy-duty diesel engines is proposed. In this system, an organic, medium-boiling-point fluid is selected as the working fluid, which also serves as the coolant for the charge air cooler and the EGR coolers. Because the exhaust temperature can be as high as 650 °C during the DPF regeneration, an exhaust cooler is included in the system to recover some of the high level exhaust energy. In the present ORC system, the expansion work is conducted by a uniflow reciprocating expander, which simplifies the waste-heat-recovery (WHR) system significantly. This reciprocating Rankine engine is more appropriate for on-road-vehicle applications where the condition for waste heat is variable. The energy level of waste heat from a heavy-duty diesel engine is evaluated by the analyses of the first and second law of thermodynamics. The second law analysis indicates that, although heat rejection from the engine coolant
Teng, Ho, Regner, Gerhard, Cowland, Chris
Technical Paper
Evaluation of a Narrow Spray Cone Angle, Advanced Injection Timing Strategy to Achieve Partially Premixed Compression Ignition Combustion in a Diesel Engine2005-01-016704/11/2005
Simultaneous reduction of nitric oxides (NOx) and particulate matter (PM) emissions is possible in a diesel engine by employing a Partially Premixed Compression Ignition (PPCI) strategy. PPCI combustion is attainable with advanced injection timings and heavy exhaust gas recirculation rates. However, over-advanced injection timing can result in the fuel spray missing the combustion bowl, thus dramatically elevating PM emissions. The present study investigates whether the use of narrow spray cone angle injector nozzles can extend the limits of early injection timings, allowing for PPCI combustion realization. It is shown that a low flow rate, 60-degree spray cone angle injector nozzle, along with optimized EGR rate and split injection strategy, can reduce engine-out NOx by 82% and PM by 39%, at the expense of a modest increase (4.5%) in fuel consumption. This PPCI strategy has the potential for meeting upcoming stringent fuel specific NOx emission levels of less than 1 g/kg-fuel and fuel
Lechner, Guntram A., Jacobs, Timothy J., Chryssakis, Christos A., Assanis, Dennis N., Siewert, Robert M.
Technical Paper
SAE Off-Highway Engineering 2003-02-01OFHFEB0302/01/2003
The evolution of diesel emissions control The development of clean diesel has been a saga of evolution punctuated by occasional milestones. Heavy-duty engine emissions tests Ricardo recently commissioned from Emprise a new full-dilution emissions measurement system at its Chicago Technical Center. Air entrainment in hydraulic systems Researchers from Opus Systems and Hosei University designed a device to remove bubbles or foam in working oils for improved performance. Turbocompounding revisited Scania has introduced a new in-line six-cylinder engine that uses technology developed 20 years ago to meet tomorrow's emissions requirements.
Magazine Issue
Evaluation of an Unconventional Diesel Engine as a General Aviation Powerplant2000-01-168505/09/2000
A novel two stroke cycle diesel engine is evaluated as a general aviation aircraft powerplant. Two certificated spark-ignited gasoline reciprocating engines are also evaluated in the same aircraft. The evaluation of aircraft propulsion performance considered only the effects of altered powerplant parameters on the range of an aircraft having a fixed gross weight and payload cruising at a given lift/drag ratio. Thermodynamic analysis finds the diesel engine can have a sea level power rating exceeding the 10,000 foot cruise power requirement by 55% with nearly equal specific fuel consumption, a low engine speed and a modest cylinder pressure. It uses a single-stage, radial turbocharger without intercooling or auxiliary mechanical scavenging. The diesel engine can significantly increase the range of a particular airplane now powered by a certificated turboprop engine. The candidate gasoline engines could not equal the turboprop-powered aircraft performance.
Addoms, Robert
Technical Paper
The Development of the Ceramic Gas Engine Co-Generation System1999-01-366710/25/1999
The Japan Gas Association has been engaged in the development of a 200-kW-class ceramic natural gas engine system to be used as a co-generation power source, subsidized by Ministry of International Trade and Industry. The engine has several new concepts to achieve high efficiency and low emissions simultaneously and to enable to use natural gas as fuel supplied with low pressure in spite of diesel engine. The co-generation system needs de-NOx system. So, we developed a urea de-NOx catalyst system for high-temperature exhaust gas. This paper will describe the result in the fiscal year 1998.
Ikeda, Katsumi, Higashino, Akira, Ishizaki, Junichi, Sugishima, Noboru
Technical Paper
Combustion and Combustion Chamber For a Low Heat Rejection Engine96050602/01/1996
For the purpose of eliminating a cooling device from conventional diesel engines, a heat insulation structure referred to as thermos structure was adapted in a low heat rejection (LHR) diesel engine. The thermosstructure is constructed by a combustion chamber wall made of Si3N4 monolithic ceramics having higher strength and fracture toughness at much higher temperature and the heat insulation layers combined with air gap and gaskets with low thermal conductivity that are located behind the combustion chamber wall. Although the insulated engine achieved reduced heat rejection from the combustion chamber with the thermos structure, improvement in fuel economy and exhaust emissions could not be realized in the case of a diesel engine with Direct Injection (DI) system. Observation of combustion process in the LHR engine suggested that insufficient fuel-air mixing may be attributed to an increase in gas viscosity and deterioration of air entrainment of fuel spray as a result of high
Kawamura, Hideo, Higashino, Akira, Sekiyama, Shigeo
Technical Paper
High Output Compound Diesel Engine Schemes - How do they Compare with State-of-the-Art Turbocharged Engines?95209909/01/1995
The paper is divided into two main parts. In the first part, section 2 and 3, the performance of turbocharged and compounded systems based on a hypothetical 6 cylinder, 8 litre, 4 cycle DI Diesel engine is discussed under two subheadings: a) the comparative performance, at rated conditions of 2200 rev/min of the two types of system operating at boost levels of 3 bar and 5 bar. b) a much more detailed comparison of the two systems over the full speed range, at the same rated levels of boost, with the 3 bar system operating with a single stage turbocharger, and the 5 bar system with a 2 stage turbocharger. In the second part, sections 4 and 5, the principle of the differential compound engine (DCE) as an integrated engine-transmission system is briefly described, followed by a comparative performance assessment of two alternative builds, both again using a 6 cylinder, 8 litre DI Diesel engine, in either 4 cycle or 2 cycle form, together with the results of a design study for a 1000 hp
Wallace, Frank
Technical Paper
Low Heat Rejection Engine with Thermos Structure95097802/01/1995
In order to eliminate a cooling system from an internal combustion engine, we studied structures to reduce heat rejection from a combustion chamber. It was known to be very difficult to increase the heat-insulation rate of a low heat-rejection engine with a coated combustion chamber wall with a zirconia layer to more than 50%. Therefore a heat flux and temperatures were calculated by using the finite-element method in order to develop a new structure for a low heat rejection engine. The calculation results were compared with the temperatures measured in the engine which was fabricated with a silicon nitride combustion chamber wall incorporated in a heat-insulation structure composed of an air gap and a gasket of very low thermal conductivity. The result was that the compound heat-insulation structure was very effective in reducing heat rejection from the combustion chamber wall to the outer cylinder made of cast iron. It was also confirmed that the temperature distributions calculated
Kawamura, Hideo, Matsuoka, Hiroshi
Technical Paper
Development of Model 6105 Adiabatic Engine93098403/01/1993
A commercially available water-cooled engine Model 6105 was modified into an adiabatic engine without independent cooling water system. The modified engine was built to have monolithic ceramic composite pistons and zerconia coatings on the firedeck of cylinder heads, the disk surface of inlet and exhaust valves, and the upper part of cylinder liners. Its supercharging system and fuel injection system were adjusted. The test results showed that such modifiation could lead to an improvement up to 5.5% of fuel consumption over the baseline engine. Having undergone a 400-hour endurance stand test, the engine was installed in a bus, and has been completed a on-board trial covering more than 10000km.
Nanlin, Zhang, Shengyuan, Zhong, Jingtu, Feng, Jinwen, Cai, Qinan, Pu, Yuan, Fan
Technical Paper
Waste Heat Recovery of Passenger Car Using a Combination of Rankine Bottoming Cycle and Evaporative Engine Cooling System93088003/01/1993
Rankine bottoming system, which operates on waste heat of engine cooling, has been developped to improve the fuel economy of a passenger car. Evaporative engine cooling system is utilized to obtain high thermal efficiency and simplicity of the Rankine bottoming system. The bottoming system uses HCFC123 as a working fluid, and scroll expander as a power conversion unit. The results indicate that energy recovery, which depends on the ambient temperature, is almost 3 percent of engine output power at ambient temperature of 25°C.
Oomori, Hideyo, Ogino, Shigeru
Technical Paper
Design Optimization of the Piston Compounded Adiabatic Diesel Engine Through Computer Simulation93098603/01/1993
This paper describes the concept and a practical implementation of piston-compounding. First, a detailed computer simulation of the piston-compounded engine is used to shed light into the thermodynamic events associated with the operation of this engine, and to predict the performance and fuel economy of the entire system. Starting from a baseline design, the simulation is used to investigate changes in system performance as critical parameters are varied. The latter include auxiliary cylinder and interconnecting manifold volumes for a given main cylinder volume, auxiliary cylinder valve timings in relation to main cylinder timings, and degree of heat loss to the coolant. Optimum designs for either highest power density or highest thermal efficiency (54%) are thus recommended. It is concluded that a piston-compounded adiabatic engine concept is a promising future powerplant.
Assanis, Dennis N.
Technical Paper
The Gas Generator Engine - A New Family of Internal Combustion Engines92006002/01/1992
This paper makes the case for the gas generator engine - a type of compounded engines - as a potential future automotive engine. The existing gas generator engines are characterized by their mediocre performance and fuel economy. The case for the new gas generator engine is based on a proposed cycle principle, which achieves simultaneous improvements in thermal efficiency and power output/weight ratio. This very attractive engineering solution may transform the mediocre existing engines into new engines of exceptional promise, which merit serious consideration.
Wang, Lin-Shu, Jeng, Yuan-Liang
Technical Paper
The Intercooled-Turbocharged Gas Generator/Expander Engine - A Feasibility Study by Computer Simulation - Part I: The Dual-Cylinder Piston-Gasifier92006102/01/1992
A new internal combustion engine is proposed. This engine is one example of gas generator engines, configured according to a newly proposed cycle principle. Turbocharging with intercooling is employed to reduce the energy loss of engine exhaust. A reciprocating piston-gasifier is used to further boost the pressure and to raise the turbine inlet temperature near its material limit. To study the feasibility of the proposed engine, a piston-gasifier is designed to consist of manifolds and pairs of cylinders with different bores. To simulate the operations of the piston-gasifier, a numerical model is developed. The manifolds and cylinders are treated as open systems and combustion is described as a one-zone heat release process. Subprocesses are described in sufficient detail. The operating characteristics of the piston-gasifier are predicted and analyzes over a broad range of operating parameters. In the second part of this article these results are used to predict the operating
Jeng, Yuan-Liang, Wang, Lin-Shu
Technical Paper
Heat Transfer Studies in an Adiabatic Diesel Engine91250211/01/1991
Numerical calculation based on finite element method are carried out to calculate the temperature field in an adiabatic diesel engine piston having diameter. 127 mm and made of aluminum alloy. The engine cylinder wall have the coated externally by a thin layer of very high grade ceramic insulating material. The isothermic distribution in the piston body and the heat flow rates to the cooling media at different loads have been depicted for both cases with and without insulation coating. The paper first reviews the current state of development of ‘adiabatic’ diesel engine in Europe, U.S.A and the Japan. This review section is followed by a brief description of the common element of hostile features, then comes the experimental program on thermally insulated components for single cylinder engine in the research center of Tabriz and finally by a theoretical section dealing with the performance potential of composed engine schemes based on ‘adiabatic’ engine operation.
Khoshravan, E.
Technical Paper
A Simulation Model for a Methanol Fueled Turbocharged Multi-Cylinder Automotive Spark Ignition Engine91241710/01/1991
The development of a computer simulation model for an automotive turbocharged multi cylinder spark ignition engine for gasoline and methanol operations is described in this paper. The model illustrates the simulation of the thermodynamic cycle comprising of compression, combustion, expansion, exhaust and intake processes. The scheme employed for matching the turbocharger and engine is also highlighted. The computed data of the above model is validated with the available experimental data. The model predicts the brake power developed by the engine, brake specific energy consumption, the nitrogen oxide and carbon monoxide emissions for both the gasoline and methanol operations, corresponding to the original and improved manifold design configurations. The overall analysis of the results show an increase in power output, lower nitrogen oxide and carbon monoxide emissions and improved brake specific energy consumption for the methanol fueled engine as compared to the gasoline version for
Mohanan, P., Gajendra Babu, M.K.
Technical Paper
High Temperature Diesel Combustion in a Rapid Compression-Expansion Machine91184509/01/1991
According to previous papers on the combustion process in LHR diesel engines the combustion seems to deteriorate in LHR diesel engines. However it has been unclear whether this was caused by the high temperature gas or high temperature combustion chamber walls. This study was intended to investigate the effect of gas temperature on the rate of heat release through the heat release analysis and other measurements using a rapid compression-expansion machine. Experiments conducted at high gas temperatures which was achieved by the employment of oxygen-argon-helium mixture made it clear that the combustion at a high gas temperature condition deteriorated actually and this was probably due to the poorer mixing rate because of the increase in gas viscosity at a high gas temperature condition. THE LHR (Low Heat Rejection) DIESEL ENGINE promises improved engine fuel consumption by eliminating the traditional cooling system and converting part of increased exhaust gas energy into useful shaft
No, Suk Hong, Kobiri, Shigeharu, Kamimoto, Takeyuki, Enomoto, Yoshiteru
Technical Paper
The New 6-Litre 12-Cylinder Engine for the New Mercedes-Benz S-Class91190509/01/1991
Mercedes-Benz presented the new S-class in spring 1991. A new 6-litre, 12-cylinder engine with 4-valve technology has been developed for the top model, the 600 SE/SEL, which is described in this paper. The engine has a maximum power output of 300 kW and a maximum b.m.e.p. of 12.2 bar (= 580 Nm). Maximum permissible constant engine speed is 6000 rpm. The new engine features a light-alloy crankcase and shares the 4-valve cylinder heads as fitted to the 6-cylinder engine, in this case each with two camshafts. Further components are the LH electronic fuel injection system, two motor-driven throttle valves, anti-knock control, two variable valve timing systems. All electronic engine functions are interlinked by a CAN interface.
Abthoff, Jörg, Bachischmid, Reiner, Brüggemann, Hans, Willand, Jürgen
Technical Paper
Second Law Analysis of Turbocharged Engine Operation91041802/01/1991
In this paper the turbocharged diesel engine operation is analyzed by means of a second law based method. The instantaneous release and storage of availability inside the several components (cylinders, manifolds, compressor and turbine) are evaluated by following a theoretical-experimental methodology that has been recently proposed by the authors. Examples of availability balances are compared for different values of some parameters which influence the combustion and the exhaust process, or for several arrangements of the engine and turbomachine system. The availability analysis of the engine transient development will show the amounts of mechanical energy employed for both in-cylinder storage and turbocharger acceleration and of those available for conversion into external output. These amounts will be compared with the fuel availability and with those destroyed during the several processes (i.e. combustion, gas exchange, turbocharger operation).
Bozza, Fabio, Nocera, Roberto, Senatore, Adolfo, Tuccillo, Raffaele
Technical Paper
Observation of the Combustion Process in a Heat Insulated Engine91046202/01/1991
The technologies which comprise heat insulated turbo compound engine are summarized as (1) establishment of heat insulation structure. (2) improvement of combustion under high temperature ambient condition. (3) establishment of energy recovering from exhaust gas.
Kawamura, Hideo, Sekiyama, Shigeo, Hirai, Katsunori
Technical Paper
Concepts, Materials, and Efficiencies of Piston Compounded Adiabatic Engines91089502/01/1991
A new practical concept for piston compounding engines is described. The calculated thermal efficiency of a fully insulated, piston compounded, overcharged diesel engine can exceed 60%. The design considerations for construction of such an engine from controlled expansion superalloys is also described.
Bell, James A.E.
Technical Paper
A Mathematical Simulation and Test to Transient Performance of Turbo-Charged Diesel Engine90167109/01/1990
A large program simulating transient process has settled a few particular questions concerned. The good agreement of calculated and experimental transient performance was obtained. It provides a convenient tool for the study and improvement in the transient performance. The influence in the transient process which was caused by the change of some parameters has been calculated by means of program. The simulating program has been used in the study and analysis for improving transient performance.
Jie, Ma, Hongzhong, Gu
Technical Paper
Energy Analysis of High Speed Vehicles in Low Mach Flight Regime90099504/01/1990
In the parametric optimization of an accelerator or a cruise vehicle for hypervelocity missions, five elements of the analysis relate to (i) vehicle configuration, (ii) weights, (iii) trajectory, (iv) propulsion and (v) control. A scheme for the overall system optimization is described. Considering weights, the concept of fixed weight growth factor in relation to gross weight is developed to illustrate the implications of technology development and staging. The analysis of the propulsion system must be based on both energy and energy availability considerations in order to assure not only the highest thrust and propulsive efficiency but also the least dependence on obtaining each component to operate at the highest achievable mechanical efficiency. A few propulsion schemes have been analyzed to illustrate methodology and benefits.
Murthy, S. N. B., Czysz, P.
Technical Paper
Structural Ceramics in Automotive Engines-Integration of Design, Development and Manufacturing Procedures90040002/01/1990
This is a descriptive review of the ceramics structural applications developed by Isuzu, Mazda, Nissan, Toyota and General Motors in spark ignition, Diesel and gas turbine automotive engines; new analytical procedures needed for the design of structural ceramics; new silicon nitride ceramics with strength of material properties approaching steel; new ceramics processing techniques which have been reduced to commercial practice in Japan on a mass production scale; and tests of vital structural components fabricated of these ceramics.
Kawamura, Hideo, Suh, Chung M.
Technical Paper
Control Design for a Differential Compound Engine89039202/01/1989
A microcomputer-based controller has been designed for a differential compound engine (DCE). Following assessment of the DCE state interactions, single input-output loop strategies were developed using a dynamic simulation. The simulation, control strategies and final implementation are described, and simulated transient responses are presented.
Hall, J., Wallace, F.J.
Technical Paper
Transient Response and Route Simulations for Heavy Vehicles with Alternative Engine-Transmission System89039302/01/1989
The paper describes the results of a study of the dynamic response of a 30 tonne truck equipped with two alternative engine-transmission systems, viz. a) the stepless differential compound engine (DCE) b) a highly turbocharged engine of the same rating with a 7 ratio stepped transmission. The comparisons cover: a) 0 - 80 krn/hr acceleration using a true dynamic and a quasi dynamic technique b) a cross country 9 km route. The DCE is shown to have superior acceleration characteristics but route behaviour of the two systems is similar.
Dequan, Zou, Rezaian, M., Wallace, F.J.
Technical Paper
Some Developments of the Effect of Fuel and Other Parameters on Diesel Engine Noise Control89013102/01/1989
The purpose of this paper is to review some Research & Developments in diesel engineering that provide pointers to resolving the potential conflict of noise reduction with fuel economy and it's attendant demand for weight reduction. Economy is not the only fuel-related problem that conflicts with noise; future diesel fuels will differ from those to which we have become accustomed, a trend which is already taking place in many parts of the world.
Waters, P. E., Haddad, S. D.
Technical Paper
Toyota Newly Developed 2VZ-FE Type Engine88177511/01/1988
Newly developed 2VZ-FE engine for CAMRY is a 2.5-liter water cooled and V-type 6-cylinder engine exported from TOYOTA for the first time. This engine has the TOYOTA original 4-valve DOHC system. That is, exhaust camshafts driven by intake camshafts using scissors gears. By its compact configuration with the gear driven camshafts, this V-type 6-cylinder engine is mounted on a front-wheel-drive vehicle which originally had an in-line 4-cylinder engine. By increasing IVZ-FE engine displacement (for domestic), compact pentroof-type combustion chambers, optimum air-fuel ratio and ignition timing by TCCS (TOYOTA Computer Controlled System) and other technologies, a high performance 153HP/5600rpm and a large torque 155ft·lbs/4400rpm have been achieved with a low fuel consumption. Quietness suitable for high-grade vehicles has been created by the cylinder. block and the crankshaft with high rigidities, a crankshaft pulley with a dual mode damper, a hydraulic-mounting and other advanced
Mayumi, Kazuhisa, Mizuno, Nobutaka, Matsuo, Masashi, Horio, Kimihide
Technical Paper
Development Status of Isuzu Ceramic Engine88001102/01/1988
Ceramics show high degree of heat resistance. But an attempt to build an adiabatic engine using ceramic materials should be carried out by full evaluation of characteristics of each ceramic material. The strength of ceramic parts are dependent on both their manufacturing processes and the mechanical and thermal stresses to which the parts are subjected. Full consideration should be given to these factors in evaluating ceramic parts. Even if a ceramic engine were manufactured after full consideration (1) to these factors, adiabatic engines proposed by R. Kamo and other researchers have had difficulty in realizing performance level and fuel economy as first suggested. Today, the adiabatic turbo compound engine still has many problems and themes to be addressed, some of which are adiabatic efficiency, combustion rate, intake air rate and method of recovering exhaust gas energy. (2),(3) On the other hand, however, an adiabatic engines with ceramic parts have already reached the stage where
Kawamura, Hideo
Technical Paper
Ceramic Components for Engines in Japan87001902/01/1987
Various ceramic components are used in many industrial fields in Japan now. Some typical examples include a high precision lathe, a large fan used in steel making and electric power plants, and ball and roller bearings. In the high precision lathe area, components are made of sintered silicon nitride and alumina. The ceramic lathe gives high precision machining capability of about 0.3µm in surface roughness, 0.1µm in surface winding, and 0.03µm in round error, primarily because of the high rigidity and low thermal expansion of the ceramics. In the large fan (∼3 m in diameter), its blade is composed of alumina. The ceramic blade results in longer maintenance-free use for the fan, primarily through the high wear resistance of the ceramic surface. The bearings are made of silicon nitride or alumina. they make it possible to use the bearings at high temperature, in vacuum as well as in dry systems.
Kamigaito, Osami
Technical Paper
Future Scope of Diesel Propulsion for Merchant Marine86120709/01/1986
Since the 1973 petroleum crisis, marine diesel engine designers had to cope with the new world market requirements that is to say lower overall transportation cost and consequently: reduced fuel consumption, low maintenance cost, capability to burn the cheapest available fuel and improved reliability. These criteria and specially the two last, are more or less in contradiction. The paper enlights how, thanks to strong research and development strengths, this goal has been achieved taking as examples the SEMT PIELSTICK four stroke medium speed engines: Their specific fuel consumption is below 120 g/HP.hour, They use a Recovery Power Turbine (compound engine) enlarging their range at high torque and reduced speed, They keep their high heat recovery capability, They allow to make freely the best choice of the propeller speed. As soon as the installation (heating, purifying, filtration and water emulsification processes) are all right, they can burn the cheapest heavy fuel available on the
Gallois, Jacques
Technical Paper
A Review of Ideas for Improving Transient Response in Vehicle Diesel Engines86045402/01/1986
Turbochargers are rightly blamed for disimproving the transient response of vehicle Diesel engines, but the serious effect of engine rotating inertia is often forgotten. Ultimately, a “no coolant” engine with lightweight ceramic parts may give substantial improvements by increasing exhaust gas temperature and at the same time reducing the inertia of engine and turbocharger components. The response of a turbocharger system can also be improved by adding energy to it, but so far such additions have required complex and costly sub-systems. A novel, cheap system is suggested.
Timoney, Seamus G.
Technical Paper
Harnessing the Neglected Potential of Rankine Compounding86053602/01/1986
This paper describes an automobile spark ignition engine which harnesses the neglected potential of Rankine Compounding. (1, 2)* The building blocks of information which support the postulation of such an engine are contained in the technical literature published by SAE, NASA, DOE, and industry. That data is relied upon as authoritative material for the description of an engine which utilizes waste heat more effectively than others of record.
Bradley, Curtis E.
Technical Paper
Recent Advances in Diesel Engine Research85097105/15/1985
This paper reviews some recent, research in diesel engineering that points the way to possible solutions to the problems facing engine designers in the next 10 to 20 years. These problems are the need for improved thermal efficiency and multifuel capability to deal with future supplies of fuel for transport and the need to make the engine more socially acceptable by reducing its noise and air pollutant emissions. It is shown that engine noise reduction need not be incompatible with the aims of reduced fuel consumption and emissions, provided that trends in these other areas are taken into account in diesel engine noise research and development programmes. It is concluded that the diesel engine of the future will have a light weight, low noise structure and will be adiabatic or limited cooled with some degree of compounding.
Waters, P. E.
Technical Paper
Ceramic Valve and Seat Insert Performance in a Diesel Engine85035802/25/1985
STRUCTURAL CERAMICS OFFER exceptional properties in terms of low density and endurance at very high temperatures, those exceeding 1000°C. These and other unique properties such as low thermal conductivity can be harnessed to serve the material needs of the future engines. In the interest of fuel efficiency and multi-fuel capability, future engines will operate at higher temperatures and be lighter in weight. Towards this end, partially stabilized zirconia (PSZ) and SiAlON components were engine tested. In a diesel engine, PSZ exhaust valves seating on PSZ seat inserts failed prematurely due to thermal shock. PSZ seat inserts showed no damage. SiAlON exhaust valves seating on metal seat inserts endured 1000 hours of cyclic operation with the exception of one lock groove failure.
Asnani, Manohar, Kuonen, Frederick L
Technical Paper
Reciprocating Engine Combustion Research Needs85039802/01/1985
A discussion of reciprocating engine combustion research needs is presented. Results of a survey ranking 31 specific research topics are also given. The twenty-three respondents gave the five highest grades to; particulate formation and oxidation mechanisms, high temperature ring friction, end gas heat transfer and high pressure transient fuel spray studies.
Borman, Gary
Technical Paper
Assessment of Positive Displacement Supercharging and Compounding of Adiabatic Diesel84043002/01/1984
A new alternative to turbocompounding for converting exhaust heat from adiabatic diesels to mechanical energy is evaluated. The concept is based on a positive displacement screw compressor and expander pair applied to an adiabatic diesel for supercharging and mechanical power compounding to form a compact and efficient power system. Predictions of theoretical performance for the system and its components are given, and the technical feasibility and potential advantages of this system are discussed.
Wurm, Jaroslav, Kinast, John A., Bulicz, Tytus
Technical Paper
Items per page:
1 – 50 of 143