气液固循环流化床换热器中预分布器结构的优化

In this study, two types of pre-distributors (nonuniform-pores and dual-baffle)for the combined solids-liquid distributor in gas-liquid-solid circulating fluidized bed heat exchanger, were designed and the characteristics of particles distribution was compared. In the experiments, the sampling method was used to measure local solids flux and a U shape pipe was used to measure static pressure drop in the lower pipe box.The effects of different superficial liquid velocities and liquid viscosities on the parameters mentioned above were investigated.The degree of distribution of local solids flux in exchanger pipe was evaluated by the non-uniformity function.The results showed that the two types of pre-distributors were both suitable for gas-liquid-solid circulating fluidized bed heat exchanger at a lower static pressure drop in the lower pipe box.Compared with the nonuniform-pores pre-distributor, the dual-baffle pre-distributor showed better performance.

边界条件对圆管层流流动的影响分析

应用Fluent软件,分别在匀速度和抛物线形速度分布入口条件下模拟圆管层流流场得到进出口静压降,并与理论值进行比较。结果显示了匀速度入口下进出口静压降与理论值误差百分比随雷诺数增加而急剧增大;而抛物线形速度入口下进出口压降与理论值基本吻合。