关键词: 复合中空热管, 充液比, 可视化实验, 等温性, 节能

Abstract: In order to solve the engineering problems of a large number of low-quality flue gas waste heat recovery and device failure caused by acid dew point corrosion，a new heat transfer component named compound hollow heat pipe was proposed. Its structure and working principle were introduced. A visual experimental device was established to analyze the mechanism of heat and mass transfer between the vapor-liquid two-phase flow inside the compound hollow heat pipe，at the same time，the experiments on wall isothermal characteristic with different filling rate were carried out. The results show that： nucleate boiling heat transfer exists inside the compound hollow heat pipe，and laminar film condensation of saturated steam is found on the inner side of outer wall when the inner tube is heated by alcohol stove and outer tube was cooled by air convection. When the wall is heated about 2 minutes and temperature increases to about 30 ℃，compound hollow heat pipe can start and work fast. When filling rate is 33%，isothermal characteristic of the wall shows its best performance. Experimental results of the compound hollow heat pipe provide the basis of engineering applications for heat exchanger.

Key words: compound hollow heat pipe, filling rate, visualization experiment, isothermal characteristic, saving energy