应用于循环流化床锅炉气固流动和燃烧的CPFD数值模拟

Application of CPFD Approach on Gas-solid Flow and Combustion in Industrial CFB Boilers

利用计算颗粒流体力学(CPFD)商业软件BarracudaTM对工业循环流化床锅炉中的气固流动和燃烧过程进行了数值模拟,通过模拟得到了炉膛从启动到稳定运行的动态变化过程。在气固流动方面,结果体现了循环流化床锅炉中炉内颗粒的整体流动形态和特性,并准确预测出磨损的发生位置;在燃烧方面,计算结果证明采用简化的煤燃烧机制是合理有效的,得到的炉膛温度分布和气体成分分布均与实际测试情况吻合。验证了利用CPFD手段预测循环流化床中气固流动和燃烧过程的潜力和可行性。

This paper performed a systematic simulation research on gas-solid flow and coal combustion in an industrial circulating fluidized bed（CFB） boiler using a commercial CPFD package BarracudaTM.Then,dynamic process including qualitative fluidization patterns and quantitative data in the furnace from start-up to stabilization was obtained.General and some unique characteristics of CFB gas-solid flow was well captured while detailed wear-intensive location in furnace was identified.The calculation results prove that application of a simplified combustion mechanism is efficient,and furnace temperature profile and gas concentration distribution are consistent with actual measurement data.This research presents a potential feasibility of applying the CPFD simulation approach to predict multiphase flow and combustion in industrial scale CFBs.