近似半椭球波纹板片板式换热器的传热特性

Heat transfer characteristics of plate type heat exchanger with approximate semi-ellipsoid corrugations

对以凸胞和凹坑中心为平面的非连续近似半椭球波纹不锈钢板片组成的板式换热器进行空气的对流传热特性试验。根据试验结果拟合出该板式换热器内空气的对流传热关联式和量纲一的流动阻力系数公式。结果表明:在对流传热方面,当较小雷诺数Re时,努森数Nu随Re增大而增长较快;当较大Re时,Nu随Re增大而增长减缓;在流动阻力方面,随着Re的增大,空气的流动压力降Δp增大,且当大Re时具有更快的增长趋势。

The convection heat transfer characteristics of plate type heat exchanger with approximate semiellipsoid corrugation consisting of dimple / protrusion shaped stainless steel surfaces were experimentally investigated in the air. The convection heat transfer correlation and the dimensionless flow resistance coefficient formula were obtained from experimental results. Results showed that,in the aspect of the heat transfer,the Nusselt number increased with Reynolds number,and increased rapidly at small Reynolds number while slowly at big Reynolds number. In the aspect of the flow resistance,the air flow resistance increased with Reynolds number and was much more rapidly as compared with Reynolds number.