Simulation Research On Performance Of Automotive Air-conditioner Louvered Fin Evaporators

Because of the compact structure of the louvered fins and the strong heat exchange capability,it was widely used in automotive air conditioners.Researches on parallel air flow heat exchangers for automotive air conditioners were mostly concentrated on the research of condensers.There were few research fields on evaporators.In this paper,the parallel flow evaporator in automotive air conditioning was the main research object,and the numerical simulation method was the main method to study the influence of the flow and heat transfer performance of the louver fins.Based on the rectangular louvered fins,the heat transfer characteristics of the elliptical louvered fins were studied.According to the three-dimensional model of the elliptical louvered fins established in this paper,the heat transfer and flow resistance of the louvered fins were studied.The comparison of the characteristics showed that the heat transfer performance of the elliptical louver fins was relatively good.The flow and heat transfer performance of elliptical louver fins under different structural parameters were analyzed.Its mained conclusions are as follows:?1?In the range of Reynolds number Re_LP of 220-403,the simulation results of the rectangular louver fins were compared with experimental results and empirical correlations.The errors of the heat transfer factor j are 8.9%and 10.7%,respectively,and the resistance factor f The errors are 11.6%and 13.3%,respectively.The error of the calculation results was within the allowable range.It was proved that the simulation method was credible and the result was correct.?2?The comparison between the two types of louvered fins shows that the percentage increase of the heat transfer factor j was in the range of 1%to 7%;the percentage reduction of the resistance factor f was in the range of 16%to 48%;the louvers of the elliptical louver fin The comprehensive performance evaluation factor j/f^1/3 was increased by 11%to 15%with respect to the rectangular shutter fins.Therefore,the improved elliptical louvered fins greatly reduce the airside flow resistance;?3?Under the condition of other structural parameters unchanged,in the range of Re_LP=225.7⁴51.3,the thickness of the elliptical louver fins was changed,and when it was 0.1 mm,the heat transfer and flow resistance performance was best;Also,when the elliptical louver fin pitch L_P=1.3 mm,shutter angle?=30°,the air-side flow resistance of the elliptical louver fins was the smallest.