层流中脉动气流横掠平板强化传热

Heat transfer enhancement with a flat plane in laminar pulsating flow

引言换热器是各种工业部门最常见的通用热工设备,广泛应用于化工、能源、机械、交通、制冷及航空航天等各个领域,是工业过程不可缺少的重要设备,提高换热器的工作性能直接影响到各个工业部门的设备能耗和低品位能源的回收程度,

In order to study the heat transfer characteristics of a flat plane with uniform heat flux in a pulsating flow,an experimental setup was built.The heat transfer of a high temperature co-fire ceramic（HTCC）heating plane cluster in pulsating flow under different Reynolds numbers（Re=433～1733）was investigated.The frequency and pressure amplitude of the pulsating flow were 30 Hz and 165 Pa,respectively.Results show that the pulsating flow enhances the heat transfer of the flat plane obviously,and the enhanced heat transfer efficiency is between 9.7% and 10.8%,increasing linearly with the Reynolds number.The results also reveal that the heat transfer flux increases linearly with the Reynolds number no matter the flow is pulsating or not.However,the slop coefficient of the enhancement under the pulsating condition is 1.26 times that under the steady condition.The addition of pulsating component in the steady flow improves the heat exchange inside the airflow.