水煤浆气化炉冷却管内气固两相流动与传热过程数值研究

Numerical Research on Gas-solid Two-phase Flow and Heat Transfer in Cooling Pipe Coal-water-slurry of Gasifier

基于欧拉-拉格朗日方法,建立水煤浆气化炉冷却管内合成气与熔渣颗粒流动、传热的相间耦合数学模型。采用O’Rourke方法处理熔渣碰撞聚并,采用离散坐标法模拟熔渣颗粒辐射传热。根据所建立的模型,对冷却管内合成气温度场进行了数值计算,与相关实验数据结果吻合较好。研究结果表明,由于熔渣的存在,使冷却管出口的温度提高;入口渣气比增大,一方面增强了整体辐射换热能力而强化辐射换热,另一方面提高了入口的总能而增大冷却管热负荷;熔渣在冷却管上半段内聚并现象显著,而下半段基本不发生聚并。

A numerical model with phases coupling for flow and heat transfer of syngas and slag particles in coolingpipe of （CWS） gasifier was developed using Euler-Lagrangian approach. The O＇Rourke method and discrete ordinates （DO） radiation model were used respectively to deal with the particle collision, coalescence and radiation. The temperature distribution of syngas in cooling-pipe was calculated on the base of the established model. By comparing with the experiment, it was found that the temperature distribution was in good agreement with the practice. The temperature of cooling-pipe outlet raised due to the existence of slag particles. When a constant flow, there is a better ratio, which can guarantee efficient operation of cooling pipe. In the first half of the cooling-pipe, the coalescence occurs frequently, however, this phenomenon almost disappeared in the latter half.