Influence Of Engine Compartment Temperature Field On Fuel Economy

With the continuous development of the automobile industry,the number of cars is increasing rapidly,and the problem of fuel consumption and environmental pollution is becoming more and more serious.The energy saving and emission reduction has gradually become the research goal that the international automobile enterprises pay more attention to.There are many factors affecting the fuel consumption of automobile,including road conditions,engine characteristics,driving technology and use environment,among which the environmental temperature has a great influence on fuel economy.Taking both north and south areas in China as an example,the temperature difference in northern winter and south summer can reach 60 degrees,and the temperature directly affects the economy of automobile.Reliability and comfort.This paper takes the engine room model as the research object,and uses the numerical simulation method to make a systematic study on the factors affecting the fuel economy in the engine cabin.Firstly,this paper introduces the current situation of CFD and the theory of numerical simulation at home and abroad.On the basis of this,the model of engine cabin is set up using CATIA.In order to meet the requirements of the simulation environment,the model of engine room computing domain is set up using UG,and the high precision grid division of engine cabin model is carried out by using software ICEM.Then,the calculation model and simulation method are determined,and the vehicle external boundary conditions and the internal boundary conditions of the engine compartment are set.Secondly,the simulation analysis of temperature field and flow field is carried out under the specific environment temperature and speed condition by software FLUENT.Finally,the velocity vector distribution map and temperature distribution map of the engine cabin are finally obtained.Through the analysis of the distribution of air and temperature in the engine room,it is found that there is a hot air reflux in the engine room.And the accumulation of heat.Finally,the model of engine cabin is set up in GT-POWER,and the parameters of engine,radiator,fan and thermostat are set up.By simulating the influence of fan speed and speed on cooling water temperature and fuel consumption,the feasibility of engine cabin model is verified.Then,by changing the temperature parameters,the changing laws of cooling water temperature and oil consumption at the environment temperature of-10,0,10,25 and 40 C were obtained.The simulation results show that different engine compartment temperatures decide different engine cooling water temperatures,and affect the fuel economy of vehicles by changing the state of cooling water temperature.In this paper,the influence of temperature distribution and temperature change on fuel economy is studied in this paper,which provides a theoretical reference for improving the structure layout of engine room,controlling the cooling water temperature of engine to improve the fuel economy.