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本文采用萘升华热质比拟实验方法测量了颗粒无序堆积床中颗粒流体之间的对流传热系数.文章首先针对堆积床中的“入口效应”进行了研究,发现入口处传热系数低于内部传热系数,其影响存在于几个颗粒直径范围内,并在6～8倍颗粒直径后达到传热充分发展区.其次对比了充分发展区的传热系数和Wakao公式的预测值,其平均偏差为11.83％.最后从孔隙率对传热的影响出发,对Wakao公式的适用性进行了探讨.“,”In the present paper,particle-to-fluid convective heat transfer coefficients in randomly packed beds were experimentally investigated by the naphthalene sublimation technique and the heat-to-mass analogy.The influence of the entrance effect is first studied.It is found that,the Nusselt number in the entrance is lower than that in the bulk of the bed and when the flow passes through 6-8 particle diameters,the heat transfer enters the fully developed region where the Nusselt number remains almost unchanged.The Nusselt numbers in the fully developed region are then compared to that of the Wakao's equation.The average deviation of experimental points and the Wakao's equation is 11.83％.Further,the applicability of Wakao's equation is discussed when the porosity of the packed bed is taken into consideration.