Numerical Simulation And Optimization Of Working Process For Large-Scale Low-Speed Two-Stroke Marine Diesel Engine

Working process of diesel engine refers to airflow,turbocharger,fuel injection, combustion,heat transfer and chemical reaction dynamics etc.Hence,Working process of diesel engine influences dynamic performance,fuel economy performance, burning noise and emission formation etc,moreover directly influences reliability and durability of diesel engine.In research of working process of diesel engine,traditional experimental and numerical simulation methods can be chose.Traditional experimental method which has long development period,high research cost,lots of difficulties,cannot meet market's demands.But applying numerical simulation to study on working process of diesel engine is an important measure which is used to demonstrate and optimize the modern diesel engine design project,forecast diesel engine's performance,research and improve the sample.Numerical simulation and optimization of MAN B&W 5S50MC diesel engine working process is performed by the AVL BOOST software in this paper.According to the diesel engine work process computation foundation and the AVL BOOST software computation principle,the diesel engine analog computation model is built up.On the base of the working model,the propel character of the diesel engine is simulated.The result indicates the analog data can tally with the empirical datum that confirmed the model is correct.On this base,with the using of the model,the influences of the compression ratio,the starting of combustion angle,combustion duration,the valve timing and exhaust system on the MAN B&W 5S50MC diesel engine's combustion performance are studied.And then,each parameter is optimized computation and the best answer is validated.According to the computation result,the structural parameters of MAN B&W 5S50MC diesel engine are changed,and the numerical simulation computation of before and after improvement diesel engine are carried out.The result indicates,the improvement diesel engine's power,economy and emission performance are improved in different degree.So the objective of the study has reached.