| In recent years, with oil resources exhausting and environment worsening, thetraditional internal combustion engine cars which depending on oil resource as energywill face serious challenges. Many motor corporations focus on developing newenergy vehicles. Some countries have issued new policies to encourage and supportthe development of electric vehicles and related components, while some countriesare about to issue similar polices. Lithium ion battery has the advantages of highenergy density, tiny volume, long cycling life and little environmental pollution, so itwill replace Ni-NH battery and become the main power source of energy vehicles inthe near future. Lithium ion battery produces large amount of heat while working.High temperature has negative effect on the performance of battery, and also it bringsthe corresponding security problems. The traditional air cooling shortened themileage of automobile since fan consumed large number energy of battery. In order tosolve the problems of traditional air cooling，this essay adopt heat-pipe heat sinks,which is made up of inorganic superconductive tube and cooling fins, it can make usethe wind from vehicle driving to cool the battery.This paper is supported by the key basic theory project [531107040300] speciallyfunded by the research business expenses for basic scientific research in centraluniversity. Based on the existing heat transfer theory and experiment results, appliedsimulation and experiment method to carry on research, the innovative points and themain research work are as followes.（1）3D numerically simulation model of radiator fins was established andnumerically simulation was performaned with the help of the software–FLUENT. Bysimulation we know that the structure parameters has relation with heat dissipateperformance of fins. Analysis the rules radiator fins by change the thickness andspacing interval parameters which provide theoretical basis for structure optimization,obtaining optimal heat dissipation performance.（2）A three-dimensional thermal simulation model for lithium ion battery wasestablished based on heat pipe. Seted the inlet and outlet in the best location onbattery box to improve fluid liquidity, steady simulation calculation was performedunder different conditions by using inorganic superconductive heat pipe combinedwith fins. The results show that the heat pipe-fins radiator has good heat dissipate performance. Unsteady simulation was also conducted by using user-defined function(UDF) write lithium ion battery heat generation changes with electric current andtime to undersdand process of battery emperature changes. The maximum temperatureon lithium ion battery was no more than50℃, the temperature difference betweenthe battery was less than5℃.（3）Experimental study on heat dissipation system was performaned to test theaccuracy of the simulation results under the same boundary conditions that simulationsettings, forced air cooling and natural cooling two cooling scheme was designed atthe same time so as to make comparision to heat pipe cooling performance. Theconclusion sugesst that the simulation results well corresponded with theexperimental results, so that the validity of theorical analysis and numerical method istested and it can meet the use of lithium ion battery requirements, the study alsoshowed that inorganic superconductivity heat pipe radiator has better performance ofcooling than foced air scheme. |
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