数值研究环形回流燃烧室紊流燃烧流场

在任意曲线坐标系下,采用四步反应机理数值研究回流环形燃烧室内燃烧过程中间及最终产物的生成.采用重整化群k-ε模型、涡团耗散模型及离散坐标法分别模拟紊流黏性、燃烧反应速率及辐射传热;采用随机颗粒轨道模型描述油珠温度、运动及其尺寸变化等过程;采用PISO(pressure implicits plit-oper-ator)算法对离散方程进行求解;在非交错网格体系下,预估该燃烧室三维两相燃烧流场以及燃烧产物分布.计算与实验结果较为相符,表明本文的数值方法及模型可靠,可为环形回流燃烧室的优化设计及污染物减排提供技术支持.

Numerical research of turbulent combustion in reversed-type annular combustor

In the arbitrary curvilinear coordinates,intermediate and final production formations of the reverse-flow annular combustor with swirl cup were numerically investigated by the four-step reaction mechanism.The renormalization group(RNG)k-ε model,eddy-dis-sipation model (EDM) and discrete-ordinate method were used to simulate the turbulent viscosity,reaction rate and radiative heat transfer,respectively.The stochastic particle trajectory model was applied to simulation of the droplet trajectories,size and temperature history.Discretization equations were solved with pressure implicit split-operator(PISO)algorithm.The three-dimensional two-phase reacting flow fielas and profiles of combustion production were predicted on a non-staggered gird system.Calculations are in reasonable agreement with experimental data.It iS shown that the numerical methods and models adopted are reliable and can be used to provide technology support for the optimum design and reducing pollutant emission in the reverse-flow combustor.