封闭空间电缆群散热的实验研究

AN EXPERIMENTAL INVESTIGATION ON THE HEAT DISSIPATION OF THE ELECTRIC CABLE GROUP IN CLOSED CAVITY

采用循环夹层水套模拟电缆地沟的侧壁和底面，用６根带有内热源的镀铬抛光铜管（发热棒）模拟电缆群，模型采用全封闭，轴向的两端和顶盖用泡沫塑料板封口。改变发热棒在空腔中的位置，在１．７×１０５＜Ｒａ＜３．５×１０５范围内得出了换热系数随发热棒位置改变的变化规律，为电缆沟中电缆的优化放置提供依据。

An experimental investigation is made to study the heat dissipation of an electric power cable group in a cable trench. The side and the bottom of the trench are simulated by the walls of a closed cavity with water jackets. The electric cable group is simulated by six polished, chromium plated copper tubes with a heater (such tubes are referred to by the authors as “heater bars”). The two sides of the axis and the top are closed by a bubble plastic plate. The heat transfer coefficient changing with the locations of the heater bars is given in a range of 1.7×10 5< Ra <3.5×10 5, which can be used as a guide for the optimal arrangement of the cable in a trench.