为高效精确模拟航空动力系统的液态燃料横向射流多尺度雾化过程,分别采用离散相模型(discrete phase model,DPM)、流体体积(volume of fluid,VOF)法耦合DPM(VOF-DPM)对横向射流雾化过程进行数值模拟,对比2种模型对横向射流雾化过程的仿...为高效精确模拟航空动力系统的液态燃料横向射流多尺度雾化过程,分别采用离散相模型(discrete phase model,DPM)、流体体积(volume of fluid,VOF)法耦合DPM(VOF-DPM)对横向射流雾化过程进行数值模拟,对比2种模型对横向射流雾化过程的仿真结果,并研究模型转换直径与破碎模型对横向射流雾化过程仿真结果的影响。仿真结果表明:相比DPM,VOF-DPM仿真得到的射流穿透深度更接近试验结果,射流雾化过程更真实,并且能够捕捉到更详细的流场信息;当模型转换直径较小时,不能转换为离散相颗粒的液滴相对较多,这些液滴仍由VOF求解,并阻挡气流导致在其周围产生小涡团;添加破碎模型对射流穿透深度和流场结构几乎没有影响,但导致离散相颗粒继续破碎成更多更小的颗粒。展开更多
Numerical simulations using volume of fluid(VOF)method are performed to study the impact of liquid-to-gas density ratio on the trajectory of nonturbulent liquid jets in gaseous crossflows.In this paper,large eddy simu...Numerical simulations using volume of fluid(VOF)method are performed to study the impact of liquid-to-gas density ratio on the trajectory of nonturbulent liquid jets in gaseous crossflows.In this paper,large eddy simulation(LES)turbulence model is coupled with the VOF method to describe the turbulence effects accurately.In addition,dynamic adaptive mesh refinement method with two refinement levels is applied to refine the size of the cells located at gas-liquid interface.Density ratio is changed from 10 to 5000 while other nondimensional numbers are kept constant.Large density ratios are considered in this paper since they are common in many practical applications such as solution precursor/suspension plasma sprays.Our simulations show that the penetration height,especially in the farfield,increases as the density ratio increases.A general correlation for the jet trajectory,which can be used for a wide range of density ratios,is developed based on our simulation results.展开更多
文摘为高效精确模拟航空动力系统的液态燃料横向射流多尺度雾化过程,分别采用离散相模型(discrete phase model,DPM)、流体体积(volume of fluid,VOF)法耦合DPM(VOF-DPM)对横向射流雾化过程进行数值模拟,对比2种模型对横向射流雾化过程的仿真结果,并研究模型转换直径与破碎模型对横向射流雾化过程仿真结果的影响。仿真结果表明:相比DPM,VOF-DPM仿真得到的射流穿透深度更接近试验结果,射流雾化过程更真实,并且能够捕捉到更详细的流场信息;当模型转换直径较小时,不能转换为离散相颗粒的液滴相对较多,这些液滴仍由VOF求解,并阻挡气流导致在其周围产生小涡团;添加破碎模型对射流穿透深度和流场结构几乎没有影响,但导致离散相颗粒继续破碎成更多更小的颗粒。
文摘Numerical simulations using volume of fluid(VOF)method are performed to study the impact of liquid-to-gas density ratio on the trajectory of nonturbulent liquid jets in gaseous crossflows.In this paper,large eddy simulation(LES)turbulence model is coupled with the VOF method to describe the turbulence effects accurately.In addition,dynamic adaptive mesh refinement method with two refinement levels is applied to refine the size of the cells located at gas-liquid interface.Density ratio is changed from 10 to 5000 while other nondimensional numbers are kept constant.Large density ratios are considered in this paper since they are common in many practical applications such as solution precursor/suspension plasma sprays.Our simulations show that the penetration height,especially in the farfield,increases as the density ratio increases.A general correlation for the jet trajectory,which can be used for a wide range of density ratios,is developed based on our simulation results.
