环腔型汽车相变蓄能器蓄能特性研究

Study on Storage Characteristics of Cavity-type Automobile Phase Change Accumulator

通过对相变蓄能器的蓄能及相变过程进行了模拟分析,得到了相变材料在蓄能过程中液相分数及温度随时间的变化规律。模拟了不同相变材料初温、不同流体初温、不同工况下相变蓄能器的蓄能情况。得到了冬天和夏天相变蓄热器初始温度不同时,液相率的变化影响不明显,设计的相变蓄能器在40 min左右完成蓄能过程,符合城市生活的一个出行时间。在进口水温为368K时对蓄热最有利,能达到最好的蓄热效果。当进口流速0.113 m/s时,此后流速继续增大,蓄热时间已没有明显的变化,这时再通过减小流体与材料间对流换热热阻来加强换热意义不大。

By using the FLUENT software,a series of experiments about storage process and melting were performed.The liquid fraction and temperature of Phase Change Material(PCM)were analyzed by the time.Different PCM initial temperatures,fluid initial temperatures and working conditions of the phase change thermal storage exchanger were conducted.The results show that,The liquid fraction variation was not apparent in summer and winter.The phase change thermal storage exchanger which the author designed finished the storage process about40minutes in accordance with a travel time of city life.368K was the perfect fluid initial temperature which can achieve the best thermal storage effect.The heat storage time of the phase change thermal storage exchanger was not apparent when the fluid initial temperatures increased to0.113m/s.The decrease of convective heat resistance will have no significance on Strengthening the heat transfer.