热管式蒸汽发生器强化传热分析研究

Analysis and Research on Heat Transfer Enhancement by Heat Pipe Evaporator

在场协同原理的基础上,推导得出了热管加热段和冷凝段的温差场均匀性因子并展开分析。改变换热单元的迎风截面积可提高各单元模块的工况流速,从而提高雷诺数(Re)与努塞尔数(Nu)。温差场均匀性因子也随Re增大,表明协同性能较好。烟气与热管表面的对流与导热方向和烟气流动方向一致,是一种较好的协同形式。工业用热管内部工质依靠重力回流,必须有一定的倾角才能满足其工作要求,该倾角必须是满足重力热管工作运行的最小倾角,也是在该流场、温度场中传热的最佳协同角。

Based on the principle of field synergy,uniformity factor in the temperature field of heating section and condensing section of heat pipe was obtained and analyzed.Through changing cross-sectional area of heat unit,the velocity of each cell module at working conditions can be increased,therefore Reynolds number(Re)and Nusselt number(Nu)can also be increased.The uniformity factor of temperature difference field also increases with Re,showing that the synergy performance is better.The direction of convection and heat conduction between the flue gas and the surface of the heat pipe is consistent with that of the gas flowing,which is a good form of synergy.For the industrial heat pipe,the backflow of internal working medium relies on gravity,and it must have a certain inclination to meet its working demand.The inclination should be the minimum one which meets the running requirement of gravity heat pipe,and it is also the best one to transfer heat in the flow field and temperature field.