Study Of Turbo-charged Diesel Engine Intake And Exhaust Process Sensitivity Based On Surrogate Model

Compared with gasoline engines, diesel engines have higher thermal efficiency, higher power density, etc. So the diesel engines are applied more widely since the invention, and have made very significant progress in all aspects. As in recent years, deteriorating air, energy conservation concept deeply rooted in human mind. In order to continue to develop the diesel engine, we must improve the thermal efficiency in order to improve the economy and emissions of diesel engines. On the other hand, while diesel engines are widely used in a lot of demanding application scenarios, such as low pressure combustion on highland, high intensity and high pressure combustion, engine performance under these scenarios will change a lot. In the combustion process, the efficient exchange process has a very significant effect on engine performance. Therefore the research on Turbo-charged diesel engine air exchange process is very necessary.Firstly, this paper introduces the single-cylinder model experiments system, based on which establishes WAVE engine performance simulation model. And then checks and verifies the combustion model, friction model, heat transfer model, the control parameter depends on the cylinder pressure curve, heat release rate curve, power, gas and other experimental data. Relying on the simulation results of the rated conditions, power factors are analyzed. Makes research programs for different intensity and different intake and exhaust state, and calculates the initial sample with WAVE model.Secondly, by precision surrogate model fitting, completes research and analysis of intake and exhausted valve on power of diesel engine efficiently, get the universal law of intake and exhaust valves on power under same condition, as well as law of power development on intake and exhaust valves in different intensity and different intake and exhaust pressure state. And completes various conditions of the intake and exhaust valves calculation and sensitivity analysis. Finally, refer to intake air mass, BMEP, PMEP development on the intake and exhaust valves, explains the principle.In addition, considering of the current engineering practice, calculates the optimum power and the corresponding optimal combination of the valves under all work conditions. Summarizes and compares the relationship between power and R value which is intake and exhaust valve diameter ratio, summarizes the variation of R values correspond the optimum power with work conditions.The full text provides a very important basis on the intake and exhaust valves design.