Research On Performance Of Turbocharged Diesel Engines And Optimization Analysis Of Exhaust System

With the rapid development and rapid progress of industrial society,people’s consumption of fossil energy is increasing day by day,a large number of harmful substances and gases are discharged into the air,and the ecological environment is seriously damaged.So the energy conservation and emissions reduction has become an important indicator of social progress,although traditional turbocharging technology has many advantages,but its drawback is not adapt to the development of the society,such as emission performance is poor,poor transient response,low torque and fuel economy under the condition of some shortcomings.This article to improve the traditional turbocharging technology,USES the sequential turbocharing technology to improve the performance of diesel engine,the design of sequential turbocharing system USES two different sizes provide high pressure gas turbocharger for the diesel engine.When the diesel engine is working under low working conditions,a small turbocharger is operated by itself.When the diesel engine is working under high working conditions,the two turbochargers operate simultaneously.In this paper,the relevant technical parameters of diesel engine are input into GT-POWER,and the simulation model of diesel engine is obtained.Diesel engine simulation model to calculate the simulation data and detailed contrast with the experimental data of diesel engine,diesel engine is verified the correctness of the simulation model,lay the foundations for the next successive supercharged diesel engine design.Scheme of sequential turbocharing system design,and then calculate the size of the supercharger related technical parameters,according to the scheme of sequential turbocharing design using the simulation software GT-POWER simulation modeling,post-processing will have supercharged diesel engine simulation model,validation of diesel engine and turbocharger matching in good state.At the same time,the diesel fuel injection quantity is adjusted to achieve the performance optimization target.The next step for the diesel engine’s compression ratio optimization,performance through multiple sets of scheme comparison selection the best compression ratio,according to the simulation data,determine the sequential turbocharing system switch of the supercharger inflection point.Design this paper successively supercharged diesel engine simulation model using pulse exhaust system,based on successive supercharged diesel engine simulation model for modification of exhaust system,design the constant pressure exhaust system,the MPC exhaust system.Exhaust pipe of the two exhaust system calculation,design formula after simulation,more performance compared to choose the most suitable exhaust pipe size,then use the simulation software GT-POWER of three kinds of exhaust system performance simulation of the exhaust system obtained from simulative calculation of experimental data,the turbine efficiency,fuel consumption rate,the maximum explosion pressure in cylinder,the output Power,such as drawing comparison,through the analysis of successive supercharged diesel engine exhaust system should choose the MPC exhaust system,in the full use of the exhaust system of diesel engine performance.