浸润性对沟槽平板微热管传热性能的影响

Effect of wettability on heat transfer performance of grooved flat micro heat pipe

对于沟槽平板微热管,浸润性是影响其传热性能的重要因素。为研究沟槽平板微热管管壳内壁浸润性对传热性能的影响,文中使用机械加工的方法在管壳内壁打磨出沟槽,以甲醇为工质,通过控制化学刻蚀时间,制备出全管壳接触角约为10°、29°、84°、87°的管壳内壁。将此结构引入沟槽平板微热管中,对其进行了传热性能实验和试样表面的表征。实验结果表明:当接触角为29°、输入功率为2.5 W时,沟槽平板微热管的传热性能最好,其传热热阻比接触角为84°的沟槽平板微热管减小了55.4%。还发现沟槽平板微热管全管内壁接触角过小,会导致绝热段工质流速减慢,从而影响传热性能。

For grooved flat micro heat pipe,wettability is an important factor affecting its heat transfer performance.To study the influence of the wettability on the heat transfer performance of the inner wall of the grooved flat micro-heat pipe shell,the grooves were polished on the inner wall of the shell by a mechanical processing method.Using methanol as the working fluid,the inner wall of the shell with contact angles of about 10°,29°,84°and 87°was prepared by controlling the chemical etching time.This structure was introduced into the grooved flat micro heat pipe,and its sample characterization and heat transfer performance experiments were carried out.The experimental results show that when the contact angle is 29°and the input power is 2.5 W,the heat transfer performance of the grooved flat micro-heat pipe is the best,and heat transfer resistance is reduced by 55.4%compared with the grooved flat micro heat with a contact angle of 84°.The contact angle of the inner wall of the microchannel heat pipe is too small,which will cause the flow rate of the working fluid in the adiabatic section to slow down,thus affecting the heat transfer performance.