• Journal of Advanced Marine Engineering and Technology
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• 제25권6호
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• pp.1260-1271
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• 2001

The simulation program which predicts the gas behavior in a spark ignition engine has been developed and verified by the comparison with the experimental results foy the MPI engine, naturally aspirated and turbochared engines with a carburettor. First paper describes the calculations of the behavior of gas in the intake and exhaust system. The generalized method of characteristics including friction, heat transfer, area change and entropy gradients was used to analyse the pipe flow The constant-Pressure model was applied for the analysis of the flow through engine valved, and the constant-pressure perfect-mixing model was applied for the flow at manifold junction. The concept of the sudden area change was used for the muffler and catalytic convertor. Fer the plenum chamber in an MPI engine, constant-pressure model and constant-volume model were both examined. Through the comparison of predicted results with experiments, the simulation program was verified by showing good prediction of the behavior of IC engine qualitatively and quantitatively under wide range of operating conditions.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.414-416
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• 2009

In order to build a transient simulation program for a high thrust liquid rocket engine(LRE), a static performance simulation program for components were made. The components were the thrust chamber (combustion chamber and supersonic nozzle), centrifugal pump (impeller and volute casing), impulse turbine, and flow control devices (control valve and orifice). Simplified mathematical models based on classical thermodynamic and inviscid theories were used to remove complexity and enhance the utility of the program. We examined the results of each program qualitatively for validate each component modeling.

• Journal of Mechanical Science and Technology
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• 제14권11호
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• pp.1296-1304
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• 2000

A program of steady-state and transient performance analysis for a 200kW-class small turboshaft engine with free power turbine was developed. An existing turbojet engine was used for the gas generator of the developed turboshaft engine, which was modified to satisfy performance requirements of this turboshaft engine. To verify the accuracy of steady-state performance program for this engine: the program was applied to the gas turbine test unit of the same type, and the analysis results were compared with experimental results. The developed transient performance analysis program using the CMF (Constant Mass Flow) method was utilized to analyze the cases of step increase and ramp increase of the fuel.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.97-103
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• 1994

This paper describes briefly the simulation program for predicting the performance of a high speed turbocharged four cycle diesel engine. The wave phenomena in the intake and exhaust systems are calculated by the characteristic method. The combustion process in the power cycle is represented by the heat release pattern which is given by the Wiebe's function or the pattern based on measured values. Turbocharger matching for the engine is described by utilizing the characteristic maps of both the compressor and turbine, which are obtained from quasi-steady states. A comparison of experimental and calculated results shows a good agreement. Then the influences of the intake system, the period of valve overlap and the characteristics of the turbine are numerically investigated by the simulation.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.150-156
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• 2008

A program based on a 2-D CFD code has been developed to simulate a gas turbine engine. 2-D Navier-Stokes implicit code with $k-\omega$ turbulent model is used in compressor and turbine. Lumped method chemical equilibrium code with 10 species of molecular is applied to combustor with assuming perfect mixture and 100% combustion efficiency at constant pressure state. Fluid properties are shared on interfaces between engine components. Compressor supplies outlet temperature and pressure to combustor. At the same time, combustor also carries temperature and pressure to turbine. The back pressure of compressor outlet is transferred by inlet pressure of turbine. Unsteady phenomena in rotor-stator are covered by mixing-plane method. The running condition of engine can be determined only by given the inlet condition of compressor, the outlet condition of turbine, equivalence ratio and rotating speed.

• Journal of Advanced Marine Engineering and Technology
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• 제13권3호
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• pp.64-71
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• 1989

In this paper, a computer program for simulation of 4 cycle diesel engines including intake and exhaust manifold system is developed. The wave action theory is applied for optimization of the intake and exhaust manifold system. The calculation results of this computer program is finely accurate and agreed well with experimental results. Accordingly, it is recognized that the developed computer program can be utillized very usefully for the design of intake and manifold system. And then, influential factors of the engine performance in the design of intake manifold is numerically investigated by the calculation only. As the results it is concluded that the inertia one of the dynamic effects on the intake and exhaust maninfold affects mainly the engine performance and the pulsation one is a side effect.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.104-112
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• 1994

The scavenging efficiency has a great influence on the performance of a diesel engine, especially slow two-stroke diesel engines which are usually used as a marine propulsion power plant. And this is greatly affected by the conditions in the cylinder, scavenging manifold and exhaust manifold during the gas exchange process. There are many factors to affect on the scavenging efficiency and these factors interact each other very complicatedly. Therefore the simulation program of the gas exchange process is very useful to improve and predict the scavenging efficiency, due to the high costs associated with redesign and testing. In this paper, a three-zone scavenging model for two-stroke uniflow engines was developed to link a control-volume-type engine simulation program for performance prediction of long-stroke marine engines. In this model it was attempted to simulate the three different regions perceived to exist inside the cylinder during scavenging, namely the air, mixing and combystion products regions, by modeling each region as a seperate control volume. Finally the scavenging efficiency was compared with three type of scavenging modes, that is, pure displacement, partial mixing and prefect mixing.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.122-129
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• 2000

This paper describes a hybrid dynamic system(HDS) modeling method and result for the drivertrain of a parallel hybrid electric vehicle(PHEV) which consists of a gasoline engine, an electric machine, and a continuous variable transmission (CVT) and proposes a drivetrain control system. The control system has an engine controller, a motor controller, a CVT controller and a supervisory controller for the coordination of all system. The controller keep the speed of engine wheel and the output torque within the optimal operation range based on the experimental data. We also developed a MATLAB/SIMULINK program for the performance simulation of PHEV drivetrain model and controllers and compared the simulation result with the experiment result in the recent literatures.

• 한국자동차공학회논문집
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• 제16권6호
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• pp.65-73
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• 2008

The purpose of this study is development of universal engine model for integrated Hybrid Electric Vehicle (HEV) simulator and a optimization of engine model. The engine model of this study is based on the MATLAB Simulink for universal and include engine fuel economy technologies for HEV. Various engine fuel economy technologies for HEV is estimated by commercial engine 1-D simulation program - WAVE. And, the 1-D simulation model of base version is compared with engine experiment result. The analyzed engine technologies with 1-D simulation are Dual-CVVT, Atkinson-Cycle and Cylinder-Deactivation System. There are improvement of fuel economy and power performance with Dual-CVVT model at part load and full load, pumping loss reduction with Cylinder-Deactivation System at idle and regeneration. Each estimated technologies are analyzed by 1-D simulation on all operation region for base data to converse simulink. The simulink based engine model maintains a signal with ECU for determination of engine operation point.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제26회 춘계학술대회논문집
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• pp.222-226
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• 2006

The purpose of this study is to analyze both the design and off design performance simulation of the PW206C turbo shaft engine used in the development of the smart UAV (Unmanned Ariel Vehicle) by KARI(Korean Aerospace Research Institute). Its mainly aims to investigate performance behavior at the un-installed and installed conditions. The ways employed to be able to analyze the performance extensively were mainly carried out by comparison of performance simulation results from both the commercial program 'GASTURB 9' using compressor maps generated by Genetic algorithms (GAs) or Scaling Method, and the engine manufacturer's program 'EEPP'. Off-design performance analysis was performed through matching of both mass flow and work between engine components. The set of performance simulations of the developed analytical models was performed by a commercial program package (GASTURB 9) that provides great flexibility in the choice of independent variables of the overall system. The results from the simulations are used to compare turbo shaft engine (PW206C) performance data obtained by the EEPP. At un-installed condition, it was found that the results with the compressor map generated by GAs were relatively agreed well than those with the compressor map generated by the Scaling Method. The performance calculation results using the compressor map generated by GAs were compared at un-installed condition and installed conditions with ECS-off and ECS-Max in variation of altitude, gas generator speed and flight speed.