CFB提升管内气固两相流动反应特性的大涡模拟

Large eddy simulation of gas-solid two phase flow behavior in riser tubes

基于梯度模式的气相亚格子模型以及颗粒动理学理论,考虑大涡模拟中过滤尺度的影响,对气固相间曳力系数进行修正,建立了气固两相流大涡模拟模型,并对提升管内气固两相流动特性进行了数值模拟,合理地预测出了提升管内气固两相环核流动结构,模拟结果与实测结果相吻合。同时,对提升管内的CO2捕捉过程进行了模拟,得到了气体组分分布以及温度场,可为循环流化床反应器的优化设计提供依据。

Based on the gradient sub-grid scale model and the particle kinetic theory,considering the effect of filtering scale during large eddy simulation,the gas-solid drag coefficient was corrected and the gas-solid two phase flow large eddy simulation model was established.Moreover,the behavior of gas-solid two phase flow was simulated,and the core-annular structure in the riser tube was reasonably predicted.The simulation results were consistent with the experimental results.Furthermore,simulation of the CO2 capture process in the riser tube was conducted,and the gas composition and temperature field were obtained,which can provide references for optimization design of the fluidized bed reactor.