Research On The Thermal Flow Field Synergy Of Electric Vehicle Cooling System And The Key Problems Of Liquid Cooling

Power battery heat dissipation of electric vehicle is the key research and heat problem.In view ofthe field synergy principle, this paper put forward a certain number of new concepts in order to do amore detailed definition for the field synergy principle; combining with simulation calculation and thefield synergy analysis method, it was rapid and accurate to guide the analysis of cooling system heatdissipation capability and choice of the cooling method by a new discriminant analysis method; it alsoresearched on the influence factors to the cooling system and battery module temperaturemeasurement test.(1)Based on the field synergy principle, this paper presented the concepts of original field andfunction field, positive synergy and negative synergy, one-way synergy and two-way synergy; thenpoint out that: when the function field and the original field were positive synergy, the movementtrend along with the direction of original field would further increase, conversely, it would reduce. Itwas application on the analysis of wind cooling condition of semi closed chamber thermal flow fieldcharacteristic, qualitatively determined the heat dissipation capability of different air-outlet patterns,and verified by simulation calculation.(2)Combining with simulation calculation and the field synergy analysis method, it was rapid andaccurate to choose the air-outlet patterns of electric vehicle power cabin, and verified by simulationanalysis based on different environment temperature and charge&discharge rate; this paper alsoresearched on the influence to the heat dissipation capability of electric vehicle by different batterypack position. Through the above research method, and introducing the concept of velocity uniformity,it was quantitatively estimated to the heat dissipation capability of different flow path ofwater-cooling plate, and verified by simulation calculation and test analysis.(3)It was analysis of other key factors influencing on the heat dissipation capability of liquidcooling system, include the temperature difference between environment and cooling liquid, and flowrate. It researched on the different temperature difference between environment and cooling liquid inorder to improve the battery module temperature distribution uniformity; by researching on the flowrate with different structure and operation condition, specific includes: different flow path ofwater-cooling plate, different battery module central clearance, different environment temperature,different charge&discharge rate, it could find the best flow rate to meet different structure and operation condition.(4)Combining with the battery module temperature field distribution of liquid cooling systemopening and closing, it introduced the temperature measuring point arrangement when the electricvehicle driving, in order to effectively monitor the battery module temperature field distributionsituation.