高温固体颗粒气动阻力系数数值计算

Numerical computation of aerodynamic drag coefficient for high temperature particles

在发动机喷管的气粒两相流场中，金属颗粒阻力的准确计算对整个流场的模拟有着重要作用。而高温颗粒与周围气相的传热会改变气相的性质，进而影响颗粒的气动阻力。采用k-ε湍流模型和强化壁面处理方法，计算了雷诺数Re在0～10000范围内，颗粒与气相不同温差情况下球形单颗粒的气动阻力系数。颗粒温度升高，颗粒所受的气动阻力随之增加，但是增加的幅度随船的增加而减小；根据计算结果，拟舍了以颗粒雷诺数为自变量的高温颗粒气动阻力系数的计算公式。通过与低肫下的实验数据的对比，验证了所拟合公式的适用性和可信性．

For gas-solid two-phase flow field of motor nozzle, the accurate calculation of metal particle drag was very. important to simulate the whole flow field. However, the heat transfer between high temperature particles and surrounding gas could change gas features, which further affect aerodynamic drag of panicles. Turbulence model and enhanced wall treatment method were used to calculate aerodynamic drag coefficient of single spherical panicle at different temperature difference between the panicles and sur- rounding gas, when the adopted Re number varies from 0 to 10 000. The results show that aerodynamic drag of single particle in- creases as particle temperature increases, but the increase amplitude decreases as Re number increases. According to calculation results,the calculation formula of aerodynamic drag coefficient of high-temperature panicle taking Re number as independent variable was fitted. By comparison with experimental data at low Re number, the applicability and reliability of the fitting formula were verified.