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一、前言 水平旋转圆筒表面的蒸发和午燥过程常见予化工、轻纺、建材等工业部门。针对不同的目的,一些文献曾研究了小直径垂直旋转圆筒的对流质交换,但未见有关水平旋转圆筒的研究报道,更未涉及高Gr数的传质问题;再者,常见的对流质交换往往伴随着热交换。有鉴于此,本文通过水在多孔介质表面的蒸发过程,测量它的局部及平均对流质交换系数,研究了高Gr数旋转圆筒表面紊流质交换时准则关联式及临界参数表达式。局部对流质交换系数hD及平均对流质交换系。h_D即:
First, the foreword Horizontal rotation of the cylinder surface evaporation and afternoon drying process is often common to chemical industry, textile, building materials and other industrial sectors. For different purposes, some papers have studied the exchange of liquid with small diameter vertical rotating cylinder, but there is no report on the horizontal rotating cylinder, nor the problem of mass transfer of high Gr. Moreover, Liquid exchange is often accompanied by heat exchange. In view of this, through the evaporation process of water on the surface of porous media, the local and average exchange coefficients of liquid on the surface of porous media are measured. The criterion correlation and critical parameter expressions of turbulent mass exchange on the surface of high Gr rotating cylinders are studied. Local to liquid exchange coefficient hD and average to liquid exchange system. h_D That is: