含有导流挡板膜片式换热器换热特性研究

Study on Heat Transfer Characteristics of Diaphragm-type Heat Exchanger with Guide Baffle

本文对含导流挡板的膜片式换热器换热特性进行研究。采用Fluent软件研究新风进风温度和速度对换热器的换热效率、传热速率等影响。研究表明换热效率仅与新风进风速度有关。进风速度是换热器的传热速率的主要影响因素。在本文研究条件下,速度从0.8 m/s增加到2 m/s,换热效率下降22.5%。新风进风温度为38℃,速度为2 m/s时,每层通道的传热速率达到15.6 W。新风进风温度为30℃,速度为0.8 m/s时,每层通道的传热速率仅为4.3 W。研究表明,新风气流通过换热器后速度越大压降越大,新风进风速度为0.85 m/s时,换热效率可达81%,因此,适当降低新风进风速度,可获得更好的热回收效果。

In this paper,heat transfer characteristics of diaphragm heat exchanger with flow deflectors were studied.The influence of inlet temperature and velocity of fresh air on heat transfer efficiency and heat transfer rate of the heat exchanger were studied by fluent.The results showed that the heat transfer efficiency was only related to the inlet velocity of fresh air and the air inlet velocity is the main factor influencing the heat transfer rate of heat exchanger.In this paper,air flow velocity increased from 0.8m/s to 2 m/s,heat transfer efficiency decreased by 22.5%.When inlet air temperature was 38℃and air flow velocity was 2 m/s,the heat transfer rate of each channel reaches 15.6 W.When inlet air temperature was 30℃and air flow velocity was 0.8 m/s,heat transfer rate of each channel was only 4.3 W.The results showed that the higher the velocity of fresh air flow through the heat exchanger,the greater the pressure drop.The results showed that the heat transfer efficiency reached 81%when inlet velocity of fresh air was 0.85 m/s.Therefore,a better heat recovery effect could be obtained by properly reducing the inlet velocity of fresh air.