Abstract: The cross-flow heat transfer was discussed on a cylinder tube embedded in the fixed bed. The bed was packed with different kinds of particles which have dissimilar thermal conductivity. The medium of heat transfer was air, and the tube was heated. Under the conditions of Rep 10 180, Db/Dp 28 116, bo/ s 0.5 0.2, the following correlation was obtained by means of the least square method：Nuf 31( bo/ s)1.4(Db/Dp)0.2Rep0.33Pr0.62. Here the Reynolds number is based on the particle surface-equivalent diameter, Nusselt number is calculated by the overall wall heat transfer coefficient, the gas thermal conductivity and the diameter of heated tube embedded in the fixed bed. It is found that for cross-flow heat transfer, Reynolds number is still an important factor affecting heat transfer. Nusselt number has relations with bed characteristic parameter Db, particle equivalent diameter in outer surface Dp and thermal conductivity of packed bed.

Key words: fixed bed, cross-flow heat transfer, overall wall heat transfer coefficient

摘要： 采用3种导热性能不同的固体颗粒为填充物，以空气为介质，在床层被加热的情况下，研究了固定床中内置圆管的错流传热. 采用最小二乘法对实验数据进行拟合，得到以床层对壁的平均给热系数、气体的导热系数和床层中被加热圆管的管径计算的Nusselt准数经验关联式: Nuf 31( b0/ s)1.4(Db/Dp)0.2Rep0.33Pr0.62, Rep 10 180, Db/Dp 28 116, b0/ s 0.5 0.2. Reynolds数以固体颗粒的等外表面积当量直径进行计算. 结果表明，在错流传热过程中，表征气体流动特性的参数Rep仍是错流传热的重要影响因素，Nusselt准数除与床层的结构参数Db和颗粒的当量直径Dp有关外，还与颗粒的导热系数 s和床层的导热系数 bo密切相关.

关键词: 固定床, 错流传热, 床层对壁的平均给热系数