水平导管内颗粒料层中的热渗透现象研究

本文针对水平导管内填充颗粒料层中的高温气体渗流现象，采用局部非平衡假设建立了多孔介质渗流传热物理数学模型并进行了数值计算。研究了不同情况下导管内填充多孔介质中的流速、气固温度和压力分布。计算结果表明，高温气体对导管内颗粒料层的热渗透作用主要是在渗流入口端区域，增大入口渗流速度以及减少给料量，导致气固温度沿轴向下降速度减慢，热渗透深度扩大，热渗透作用区域内的物料温度水平提高。在热渗透作用区域，孔隙率对流场和压力损失有很大的影响。研究结果对于移动颗粒反应器和输送机的设计与运行具有一定的参考作用。

Heat Penetration into Feed Stream within Horizontal Pipe

High heat penetration into feed stream within horizontal pipe is described mathematically with a heat and mass transfer model. The distribution of gas velocity and its pressure, the temperature field of gas and solid in the moving particle bed are calculated at different conditions. The results show that the thermal infection to the moving packed-bed particles by the seepage flow fluid is high only in the position near the gas entrance. The thermal penetration thickness tends to increase with the seepage flow velocity and decrease with feed rate. In the thermal penetration influence field, the porosity of solid bed has important effects on the gas velocity field and the pressure loss. The results are useful in the conceptual design of grain feeder and protection of the feeder from thermal seepage of the high temperature fluid in the reactor.