高温热管声速极限的实验研究与理论分析

高温热管是公认的被动式高温传热器件,以及明显高于相同几何尺寸金属材料的当量导热率,使其成为研究热点,并具有广泛的应用前景.在高温热管的蒸汽流动中,当喉部流速达到声速后,会出现声速传热极限,主要表现为冷凝段温度持续降低,传热量停滞不增,以及蒸汽的阻塞状态.本文设计、制备了高温热管传热器件,以高频感应方式为热源,盘管式水冷...

Analytical and Experimental Study of the High Temperature Heat Pipe Sonic Limitation

As one widely recognized excellent passive heat transfer device using in high temperature conditions,high temperature heat pipes(HTHPs)have a noteworthy higher effective thermal conductivities than the ordinary metal materials whom has the same geometric sizes,which makes HTHPs being a research focus point with a broad application prospect.When the throat velocity of vapor flow in HTHP has exceeded the sound velocity,HTHP will reaches the sonic limitation that is meanly manifest as the continuously decreasing condenser temperature,the stagnant heat transfer performance,and the blocking state of the vapor flow.In this work,a high heat transfer performance HTHP was designed and fabricated.A heat transfer test-bed which used high frequency induction as a heating source and coil water tube as a cooling source was adopted to study the HTHP sonic limitation,the analytical model was used to verify the sonic limitation.The basic physical properties of HTHP in frozen startup process and steady state were tested in high flux heating conditions.The results demonstrating that both the length-diameter ratio,heating flux and operating temperature effect significantly on the HTHP sonic limitation.