论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。Development process of high power diesel EFI controller developed by DALIAN LOCOMOTIVE AND ROLLING STOCK Co., Ltd. CNR GROUP was introduced in this paper including analysis about EFI technical requirements of type 240, 265, 270 and 280 series diesel. The principle and method used to form EFI System adopting master-slaver controller,and the hardware of EFI controller was introduced.Control principles, construction of software and control flow were also included.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。Exhaust Gas Recirculation (EGR) is used widely due to its efficiently impacts on the NO x reduction with the increasingly stringent emission regulations. However, the introduction of EGR can lower in-cylinder oxygen concentration and increase combustion losses, which will increase soot and brake specific fuel consumption (BSFC) simultaneously. In this paper, the integrate optimization for the combustion system and fuel injection parameters, the introducing way of EGR, turbocharger matching, fuel injection strategy was conducted in a heavy-duty diesel engine with common-rail fuel system. The results showed that, soot, BSFC and the maximum in-cylinder pressure can been lowered by properly reducing compression ratio, optimizing the structure parameters of combustion chamber (shrink diameter and bowl depth,etc.) as well as the usage of Bosch injector with eight taper holes. Relative to high pressure EGR (HP-EGR), low pressure EGR (LP-EGR) can significantly enhance EGR recyclability and air/fuel ratio (AFR) at low speed conditions, thus improving soot and BSFC performances. Conversely, HP-EGR can reduce pump losses and BSFC at the medium and high speed conditions. Compared to constant pressure system, the EGR recyclability and the NOx-BSFC trade-off can be improved by pulse boost systems for HP-EGR. The trade-off between NOx , soot and BSFC will worsen with the increased intake charge temperature at high load cases under the low speed. However, the effects of intake charge temperature on the engine performance and emissions can been weaken via optimizing turbocharger systems, EGR system, fuel injection strategy, etc. With increasing engine power, two-stage turbocharger (2TC) can obviously improve EGR recyclability and the trade-off between NOx , soot and BSFC compared to single-stage turbocharger at full load conditions under medium and low speed, which showed obvious advantages and potential in the case of meeting Euro IV and Euro V regulations without any after-treatment. At low load conditions, the NOx ,soot emissions and the maximum pressure rise rate (MARR) can been efficiently reduced by lowering in-jection pressure and postponing injection timing under single injection strategy. At high load conditions under low speed, soot and BSFC can been improved by the same control strategy used at low load. At high speed conditions, it is necessary to employ post injection and higher injection pressure to reduce engine emissions and BSFC. Keywords: Diesel engine; Turbocharger;Exhaust gas recirculation (EGR); Combustion; Emissions

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。 In these recent years, according to the environmental crisis and the influence of gasoline and diesel fuels in it, and at the other hand, the high cost of fuel is caused an interested in the manufacturers to use natural gas fuel. Due to gas density is much lower than liquid fuel, the natural gas will occupy more space than them and volumetric efficiency will be reduced. In this regard, Miller cycle as the fifth thermodynamic cycle in internal combustion engines is discussed. Increasing the expansion ratio against the compression by Changing in the intake valve timing is the main characteristic of this cycle. In this study, AVL FIRE software is used to simulate D87 gas engine. As, the close cycle cannot investigate valve lifting and also turbo charging effective, then a 1-D simulation by GT Power is used. After their coupling and validating with each other, 4 cam shaft timing has been used as well as Otto cycle. The result has been shown decreasing in maximum pressure and temperature with slight increase in the power. Also due to decrease in peak temperature, NO x and CO are decreased obviously.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。 Choosing one marine controllable intake swirl diesel as the research object,this paper does some calculation and analysis on the intake flow field by using a three-dimensional flow field analysis software,then,obtains the swirl ratio and the flow coefficient of the target diesel in different valve lifts and intake baffle angles , and finds that the intake swirl of the diesel has a two-stage characteristics,namely the value of the swirl changes from high to low.On basis of the calculation and analysis of the diesel air intake system flow field,this article completes the structure optimization design of the diesel intake,and gets the laws of the swirl ratio and the flow coefficient influenced by the structure of the diesel intake.At the same time,this paper verifies the calculating results through using the steady flow test of the diesel air intake system,and ensures the accuracy and reliability of the diesel air intake system calculating analysis and design optimization.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。 It is very important to identify the T.D.C.phase in the combusting analysis of I.C. engine. Erroneous determination of T.D.C. has been recognized as the major error source for thermodynamic cycle calculations, such as mean indicated pressure, heat release curves and so on. The methods of T.D.C. determination in the indicator diagram of the medium speed marine diesel engine is studied in this paper. Analyzing results indicate that T.D.C. can be determined by detecting the piston displacement directly with an electric-capacity or microwave transducer. This method is more accurate but more additional cost and mounting problem. To use non-fired cylinder pressure maximum point adds T.L.A thermodynamic loss angle is more applicable for the medium speed marine diesel engine. And the key problem of the later method is T.L.A. determination. In this paper, the effect factors of T.L.A. are analyzed. An ideal polytropic exponent curve are introduced and compared with the real polytropic exponent curve to estimate T.L.A and the program is compiled. T.L.A. of a certain diesel engine is calculated and its T.D.C. phase is identified.Comparing the calculated T.L.A. with the tested T.L.A. in experiments, which proves that this method is feasible and the result is correct. It supplies a gap about the study of the T.D.C determination for the medium speed marine diesel engine.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。 In order to study the effect of supporting structure on power performance of ball bearing turbocharger, the FEM model of ball bearing rotor system with damper is established. Considering the effect of damper on bearing stiffness of rotor system, the analyses of critical speed, imbalance response and axes track for rotor system with and without damper are carried out. The results show that damper can adjust the critical speed of rotor system after changing the total bearing stiffness of rotor system .According to the analyses of imbalance response and axes track, the effect of damper to restrain vibration of rotor system is obvious. Based on the verification test, the analysis results are found to be in reasonable agreement with the test results.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。 Establish the working process model of the gas engine by applying AVL-BOOST software, simulate the engine work requirements, calculate the different excess-air coefficient pressure ratio compression ratio parameters and the whole engine performance, Then obtain the calculation data of AVL-BOOST software during the gas engine development.By simulation calculation, reduce the actual engine verification times, shorten the development period, improve the work efficiency, provide the direction for the latter optimization matching, which is available for gas engine develop design and optimization.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。This paper is aimed at the friction condition transition (FCT) and scuffing problems of piston ring and cylinder liner (PRCL) in high power density diesel engine. ¬ Friction pairs are selected for testing: chrome-plated (CP) cylinder liner sliding against plasma-sprayed molybdenum (PSM) and the chromium nitride coating with physical vapor deposition (PVD) piston rings, Based on the chaos theory, friction force obtained from the designed starvation experiment was used to characterize the FCT, and then explore the evolution process and its related action mechanism for the two sets of friction pairs. Results showed that attractors constructed from the signal of friction force in the phase space can describe the regularity which seems irregular. When the load and temperature were in the lower range, both pairs presented excellent anti-scuffing behavior, while the load and temperature increased to the higher range,both anti-scuffing behavior became weaker, However,PVD/CP was better than PSM/CP. The scuffing mechanism of PSM/CP was mainly partial adhesion and material transfer, and PVD/CP presented high temperature locally plastic deformation.

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。This text introduces three kinds of hard rolling technologies applied and tested in the production of internal combustion engine parts. The valves produced by this technology are one time approved by MAN Diesel & Turbo for quality certification. Using hard rolling technology in the production of cylinder liner, piston crown, crankshaft and connecting rod achieves very good results. It can effectively reduce the carbon deposition of combustion chamber, improve the reliability and lifetime of the parts, which lays the foundations for further improving the performance of internal combustion engine. Keywords: rolling,hardening, reliability

论文已在中国上海举行的2013年CIMAC大会上发表。论文的版权归CIMAC所有。Though diesel engine Particulate Matter (PM) emission was widely investigated, the contribution of diesel fuel and lubricant were less studied because of the engine can not run without lubrication. Dimethyl Ether (DME) is an alternative fuel for diesel. Its molecular formula is CH3-O-CH3. When it is burned, there is no carbon or PAHs generated like conventional natural gas, gasoline, diesel, biodiesel,et al. To take the advantage of DME combustion, a CIengine was applied to run on diesel and DME, respectively, to study its PM emission characteristics. In the study, HORIBA MDLT-1302 system was used to sample the engine exhaust PM mass emission. The filter paper was weighted by a Sartorius ME5 electronic balance. PM number vs diameter distribution was detected by an Electrical Low Pressure Impactor (ELPI).The experimental results show that DME engine PM number is some 2 order lower than that of diesel engine. Lubricant contributes more under high engine load and speed conditions. Compared with DME operating conditions, lubricant contributes about 20% of PM mass.