干熄焦炉内三维流动及传热的数值模拟

以Fluent软件为平台,通过流体在多孔介质中的流动模型来处理冷却气体在干熄焦炉内的三维流动,借助于UDS和UDF进行二次开发,建立干熄焦炉内冷却气体及焦炭的流动传热模型,并分析了循环风量对气固换热的影响。结果表明,冷却室气体在通过斜道进入环形气道时有偏流现象,即靠近总出口附近的斜道有更多的气体流出,且气流速度最快;气体的压力损失主要发生在冷却室;冷却室内周边的换热效果比中心换热效果要好。模拟计算发现,循环风量为200 000m3/h时,换热后的冷却气体温度为1101K,焦炭温度为439K,这不仅满足了焦炭的冷却要求,而且还能提供用于供暖或发电的高品位热量的循环气体。

3D numerical simulation of flow and heat transfer in coke dry quenching process

A mathematical model for quenching gas flow and heat transfer between gas and coke in the coke dry quenching (CDQ) unit was established. In the model, secondary development was done on the platform of Fluent by employing the user defined functions (UDF) and the user defined scalars (UDS). The calculation results show a bias flow of quenching gas in the chutes, i.e. more gas flows to the annular gas passage through the chutes near the outlet with relatively larger velocity. The pressure loss of the flowing gas mainly takes place in the cooling chamber, and the heat transfer rate between gas and coke near the side in the chamber is larger than that at the center. Simulation results find that the heated gas temperature can reach about 1101K at the gas outlet while the cooled coke temperature decreases to about 439K at the coke outlet when the circulating air volume is 200000m³/h. This can not only meet the cooling requirement of the coke but also supply the recycle gas with high grade heat for further heating or power generation.