微小空间内多孔表面上的沸腾实验研究

1引言微小空间内的沸腾在电子器件冷却、航天热控、微型换热器以及核反应堆的冷却等领域中有着广泛的应用，因此对其沸腾机理的研究具有重要的意义。过去微小空间内的沸腾研究主要是针对光滑表面［‘－‘1，已证明在微小空间里，沸腾换热受空间尺寸的影响要比大空间大。对于多孔表面在微小空间内的沸腾研究则相对较少。本文对矩形槽道表面和烧结型多孔表面在微小空间里的沸腾进行了实验研究。2实验装置实验装置如图1，实验段是3O0mm长的紫铜管（包括矩形槽道管和烧结型的多孔管），内插不同外径的不绣钢管，形成不同间隙的环形小空间。在内…

BOILING HEAT TRANSFER FROM POROUS SURFACES IN NARROW SPACE

The investigation of saturated boiling heat transfer was performed from porous surfaces in narrow space formed by two concelitric tubes with two open ends at atmospheric pressure. Experimental results show that for the grooved tubes with inserted tubes the boiling heat transfer coefficiellts increase with the decrease of gap size. The boiling critical heat flux decreases with the decrease of gap size. The grooved surfaces can also augment the critical heat flux. Sintered porous surfaces, in pool boiling, can enhance boiling heat transfer, but the boiling heat transfer from these surfaces is affected little by gap size of narrow spaces.