Research And Optimization Of Engine Cooling Fan Tip Parameters Based On CFD

In recent years,China's auto industry has developed rapidly,and now it has become the largest auto production and sales country in the world.The automobile industry plays a very important role in our national economy and has become one of the pillar industries of the national economy.As one of the most important parts of a car,the heat dissipation performance of the engine directly affects the performance of the car.The cooling fan of the engine is an important part of the heat dissipation system,and its performance determines the working state of the engine to a certain extent.Therefore,it is necessary to study the performance of the engine cooling fan to ensure the performance of the car.This paper takes engine cooling fan as the research object,firstly,the research on the cooling fan in CFD and structural optimization design is investigated,and the research status at home and abroad is briefly explained.Then the performance test method of engine cooling fan is introduced and its performance index and the calculation method of these index are explained in detail.Then,according to the actual situation,this paper selects the C-type test device and introduces the specific test flow.Through the specific test,the specific test performance index of the fan to be studied is obtained.The computational model of engine cooling fan was established,and the model was meshed by Hypermesh software.Fluent software was used to calculate the model,and the simulation value was compared with the test value.The result shows that the overall error of the two is within 6% and the change trend of the two is the same,so it can be considered that the simulation results are consistent with the test results,which proves that the established calculation model is available,and also illustrates the feasibility of CFD simulation method to study the aerodynamic performance of fans.The engine cooling fan is an important part of the vehicle cooling system.Static pressure and shaft power are important indicators to evaluate its aerodynamic performance,and the tip of the blade as a main part of the fan work has a great influence on the aerodynamic performance of the fan.In this paper,the three parameters of tip mounting angle,tip chord length and tip arch height are selected as the research object.Firstly,according to the single factor analysis method,it is found that the increase of the tip mounting angle will increase the static pressure,but at the same time the power will also be increase.In the scope of this study,as the length of the tip chord increases,the static pressure and power both increase first and then decrease,but the change of power is far less than the static pressure change;The increase of blade tip arch height has no obvious effect on static pressure,but the increase of power is obvious.Secondly,orthogonal tests were carried out on the three factors to optimize the blade tip parameters,and the optimization method of the fan blade tip parameters was given,and a new fan with static pressure increased by about 7% compared with the original fan and power loss decreased by about 5% was obtained.Finally,the optimization results are analyzed from the aspects of fan performance curve and fan flow field characteristics,and the feasibility of the orthogonal test optimization method is verified,which provides a reference for the subsequent structural optimization design of the fan.