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报道了恒热流条件下，用红外热成像法测量颗粒填充通道壁面温度分布的结果．发现加热壁面出现随机不均匀分布的相对高温区，其原因可能是由于在颗粒与加热壁面直接接触的区域流体流动速度偏低，甚至出现“滞止”区所致．这说明，由于壁面对颗粒堆积的自然限制，颗粒填充结构在壁面附近区域的孔隙率以及孔隙通道的大小和形状都发生变化，从而影响流体的流动和传热．由按面积加权所得出的壁面平均温度计算Ｎｕ与Ｒｅ关系，其变化规律有可能表明流体在孔隙内的流动状态发生了改变．
The results of measuring the temperature distribution on the wall of particle filled channel by infrared thermography were reported under constant heat flow conditions. It is found that the relatively high temperature zone with random uneven distribution of heating wall may be due to the low fluid flow velocity in the area where the particles are in direct contact with the heating wall and even the “stagnation” zone. This shows that due to the natural limitation of the wall on the particle packing, the porosity of the particle-filled structure in the vicinity of the wall and the size and shape of the pore passage both change, affecting the fluid flow and heat transfer. The relationship between Nu and Re is calculated from the average wall temperature calculated by area weighting. The variation of Nu and Re may indicate that the fluid flow in the pore has changed.