Optimization Of Cooling System Matching For Vehicle Diesel Engine By Means Of Numerical Simulation

With continuous improvement of the engines strengthen level, the heat flux density of the engine is increasing, but it causes the problem that the components of cooling system can't match well and the coolant temperature is exorbitant. Therefore, it is key to resolve cooling performance at high-powered density that the cooling system matches and optimizes with engine. Additional, the flux of cooling water is very important to the engine's cooling performance, finding the most appropriate coolant flux under different working conditions of engine not only can ensure that the engine works in the most appropriate range of temperature, but also improve the efficiency of the cooling system and engine's performance effectively.Based on the numerical simulation, the cooling performance for the cooling system of a heavy-duty vehicle diesel engine were analyzed and researched in this paper, the main contents are as follows:Firstly, according to the arrangements of the components of cooling system, the one-dimensional simulation model was established by Flowmaster, and calibrated the model by the experimental data. Then change some parameters of the cooling system. The influencing factors of the cooling performance were analyzed in detail.Secondly, based on the established calculation model, change some parameters such as engine cooling jacket heat flux and pump speed. Then study the influence of different cooling jacket heat flux to engine cooling performance, At the same time find the best water pump running state under the different working conditions of engine, get the appropriate speed of the pump, And provide the basis for control strategy of the electric water pump. Lastly, the research shows that cooling system components of the diesel engine can meet the demand of the engine cooling performance, but there are some problems such as large pump flux, and when the engine runs under the conditions of low speed and high temperature in summer, the coolant temperature is exorbitant, it need to increase the radiator efficiency. The simulation and analysis show that cooling jacket heat flux is deeply influence the engine's cooling performance; it can optimize the pump flux and improve the performance of the engine cooling system under different working conditions of engine.