【摘要】 实验采用涂覆-热处理法制备了纳米白炭黑-硅橡胶膜(SiO2-PDMS)滴状冷凝强化传热管,研究了纳米SiO2在铸膜液中质量分数及热处理温度对热通量和冷凝传热系数的影响;同时对纳米白炭黑-硅橡胶膜(SiO2-PDMS)滴状冷凝强化传热管表面进行了SEM,FT-IR及接触角分析。实验结果表明:实验所制传热管均实现滴状冷凝现象;纳米SiO2在铸膜液中质量分数影响传热管传热性能,随纳米SiO2质量分数增加,表面水接触角增加,其中纳米SiO2质量分数为0.1%时,传热管表面水接触角可达125.85°,其冷凝传热系数比相应的膜状冷凝提高了3.1—3.3倍,热通量是相应膜状冷凝的1.42—1.44倍;热处理温度为265℃时,传热效果最好。更多还原

【Abstract】 The dropwise-condensing enhanced heat transfer pipe was prepared with nano silica-silicone rubber membrane( SiO 2-PDMS) by coating-heat treatment,investigating the effect of nano silica’ s mass fraction in the casting solution and its heat treatment temperature on the heat transfer coefficient and heat flux. Meanwhile,the nano silica-silicone rubber membrane( SiO 2-PDMS) dropwise condensing strengthening on the surface was analyzed by SEM,FT-IR and contact angle. The experimental results show that the strengthened heat pipes prepared all achieve the dropwise condensation phenomenon. The mass fraction of nano silica in the casting membrane affects the heat transfer performance of heat pipe. The surface water contact angle increases with the increase of nano silica mass fraction,and when the nano silica mass fraction is 0. 1%,the surface water contact angle of heat pipe reaches 125. 85°,with its condensation heat transfer coefficient 3. 1-3. 3 times that of the corresponding filmwise condensation,and the heat flux 1. 42-1. 44 times that of the corresponding filmwise condensation. When the heat treatment temperature is 265 ℃,the heat transfer result achieves the best.更多还原