扁热管在不同工况下的传热性能研究OA

To investigate the heat transfer performance of flat heat pipes under different operating conditions,using deionized water as the working fluid,a copper flat heat pipe with a length of 300 mm,thickness of 1 mm,and width of 9 mm is taken as the object.The experiment studies the effects of input power,operating angle,and horizontal position of the heated end on the steady-state temperature distribution,maximum power,and thermal resistance of the heat pipe.The test system consists of a heating module,condensation module,and data acquisition module,measuring wall temperatures under different conditions at a room temperature of 20℃.The results show that when placed horizontally,the maximum heating power is 5.5 W,and thermal resistance increases with rising power,0.93℃/W at 3 W and 3.10℃/W at 5 W.Increasing the inclination causes thermal resistance to rise and maximum power to decrease;at 20°,the maximum power drops to 5 W,and thermal resistance reaches 4.32℃/W,suggest maintaining a horizontal or slight inclination angle(≤5°).The position of the heating end has the most significant impact:when the distance between the hot and cold ends is shortened from 260 mm to 195 mm,thermal resistance sharply decreases to about 0.6℃/W;however,further shortened to 130 mm led to an increase of thermal resistance to about 1.5℃/W due to fluid retention,indicating the existence of an optimal distance range(approximately 65%of the pipe length).Proper adjustment of the hot and cold end distance can significantly reduce thermal resistance without changing the total length of the heat pipe,providing experimental evidence for optimizing the layout of flat heat pipes in thin and light electronic devices.