Study On Simulation Of Intake And Exhaust Characteristics Of SC11CK Diesel Engine Based On GT-Power

Internal combustion engine is a kind of energy power machine which can convert heat energy into mechanical energy. As the heart of vehicle, it not only provides strong power for vehicle, but also proves to be one of the most complicated and frequent working parts, and it plays a decisive role in improvement of vehicle performance. With the accelerating pace of engine products replacement and the continuous improvement of requirement, the traditional methods for designing IC engine can not yet satisfy the requirement of modern engine design with optimal design and rapid development. The progress of modern computer technology makes it possible to have numerical simulation design of IC engine. According to the simulation results of engine performance based on computer technology, it is convenient to work fast to conduct theoretical analysis and performance evaluation of the design objects. Therefore, it is useful to greatly reduce experimental work, lower development cost, shorten development cycle effectively. At last, the goal of accelerating development speed and improving development level is achieved. Simulation design method has been more and more widely used in modern design and performance optimization of IC engines.In this paper, gas flow simulation calculation theory of IC engine and modern simulation design method is applied, and its control equations were deduced based on finite volume method (FVM). Aiming at the SC11CK diesel engine, a simulation model was established by using GT-Power software and calibrated by comparing the date between the GT-Power model and the engine test rig. Based on this, great efforts were put on this model’s intake and exhaust system. By analyzing some parameters including the length and diameter of the intake pipe, the volume of steady-pressure box and pipe length between the output of inter-cooler and input of the steady-pressure box, the intake performance and fuel economy of the engine were assessed. Then the law of the intake pipe’s structural influence on the IC engine was acquired, and possible optimization ways were put forward. It was shown by calculation that the engine’s dynamic and economical performance was improved.Since that valve timing poses immense effects on the air exchange process, and matching with inlet and exhaust pipes also brings major impacts on the performance of IC engine, the paper presented further study on the influence law of different valve timing strategy to nitrogen oxide emission performance of the engine by GT-Power software. The simulation study was focused on the change of intake lag angle, exhaust advance angle and valve overlap angle. Finally it can be concluded that due to the internal EGR created by changing the exhaust lag angle and the intake advance angle, the NOx emission can be reduced efficiently, and then it provides reference for improving diesel engine’s emission of NOx.