Research On Control Strategy Of Engine Cooling System Based On GT-Suite And Simulink Coupling

With the widespread use of automobiles,the issue of the energy consumption and emission of automobiles have become increasingly prominent.In recent years,the engine has been developing in the direction of “high power and small displacement”,which has led to an increase in the power density and heat load of the engine.Due to its own working characteristics(passive regulation),it has been difficult for t he conventional cooling system to meet the performance requirements of complex and variable operating conditions of engines and automobiles.Studies have shown that the cooling system,only 3% to 5% of the whole running time,is working under the suitable capacity.Therefore,it is imperative to study a more efficient and intelligent cooling system.In response to various operating conditions of engines,how the intelligent cooling system coordinate and control each component's effective operation is the key to adapting and meeting the com plex needs of automobiles and engines.Combining the test and simulation methods,the engine and vehicle test are carried out and the simulation model of the vehicle intelligent cooling system is established.Based on this model,the intelligent cooling system strategic research is carried out under the NEDC.The main research contents and results are as follows:(1)An engine universal characteristic test and a gasoline-powered vehicle test under the NEDC were carried out,and a large number of test data were obtained.According to the obtained test data,the vehicle cooling system model was established and verified,which shows that the model is well matched to the actual operating conditions.(2)Based on the vehicle cooling system model,the intelligent cooling system is design,and the joint work MAP of the electronic water pump and the electronic fan is calculated.Then,the analysis of the vehicle cooling system under the NEDC cycle condition was carried out.It was found that the warm-up process was long,the coolant temperature oscillation was large during the thermostat opening process,and the cooling capacity was excessive under partial load conditions.For this reason,it is necessary to study and develop appropriate control strategies by Simulink.(3)The coupling and simulation calculation of the intelligent cooling system model and the control strategy model are finished.Compared with the original cooling system,the intelligent cooling system has a good effect on speeding up the warm-up process,reducing the coolant oscillation and the fuel consumption of the whole vehicle.In the process of warming up,the auxiliary heating method can effectively shorten the warm-up time.During the opening of the thermostat,the temperature fluctuation of the coolant is reduced from 5.1°C to about 2°C,so the effect is obvious.the intelligent cooling system can reduce the fuel consumption of the whole vehicle by about 2% under the NEDC.The research results show that the cooling system based on GT-Suite coupled with Simulink can not only optimize its own operating state through reasonable control strategy,but also can significantly improve the fuel economy of vehicle,which is of great significance to the energy saving and emission reduction of vehicle.