We present iterative pressure Poisson equation method for solving the viscous incompressible Navier-Stokes equations. Comparing with the pressure Poisson equation method, it uses the increment of the pressure, the dif...We present iterative pressure Poisson equation method for solving the viscous incompressible Navier-Stokes equations. Comparing with the pressure Poisson equation method, it uses the increment of the pressure, the difference of two successive pressures (pkn+1 and pk+1n+1), instead of the pressure p(n+1) as an unknown variable. We apply it to a fourth order accurate staggered mesh compact difference scheme, simulate the driven flow in a square cavity with Re = 5000 and 10000.展开更多
(1) A staggered mesh compact difference scheme is presented for solving the unsteady viscous incompressible Navier-Stokes equations. It is fourth order accurate both in the spatial direction and in the time direction,...(1) A staggered mesh compact difference scheme is presented for solving the unsteady viscous incompressible Navier-Stokes equations. It is fourth order accurate both in the spatial direction and in the time direction, at least third order accurate on the boundary; (2) Describe a pressure-Poisson-equation that is equivalent to the discrete continuity equation provided the discrete momentum equations remain. The discrete continuity equation may have derivative boundary conditions,e.g., the compact difference scheme; (3) A new ADI iterative method is proposed.The pressure-Poisson-equation is in the discrete form. It is difficult to be solved with a usual ADI method. We translate it to be tridiagonal in each spatial direction of each step of the ADI iterations, then add a pseudo time term to get a tridiagonal equation which is easily to be solved; (4) The driven flow in a square cavity with Re = 10000 is simulated numerically.展开更多
为研究飞秒脉冲激光冲击强化中等离子体压力时空演化规律,利用考虑电子态密度(DOS)效应的模型计算了电子热容和电声耦合系数随电子温度的演化规律,并与采用QEOS(quotidian equation of state)模型计算结果进行了对比;提出DOS飞秒脉冲激...为研究飞秒脉冲激光冲击强化中等离子体压力时空演化规律,利用考虑电子态密度(DOS)效应的模型计算了电子热容和电声耦合系数随电子温度的演化规律,并与采用QEOS(quotidian equation of state)模型计算结果进行了对比;提出DOS飞秒脉冲激光冲击强化模型,计算得到电子温度、晶格温度、等离子体羽位置时间演化规律和等离子体压力时空演化规律,并与QEOS飞秒脉冲激光冲击强化模型结果进行了对比。结果表明:DOS飞秒脉冲激光冲击强化模型计算得到的等离子体羽位置随时间的演化规律与实验结果吻合程度更好;增加激光能量或功率密度、考虑电子DOS效应会增加电子、晶格温度和等离子体压力。展开更多
文摘We present iterative pressure Poisson equation method for solving the viscous incompressible Navier-Stokes equations. Comparing with the pressure Poisson equation method, it uses the increment of the pressure, the difference of two successive pressures (pkn+1 and pk+1n+1), instead of the pressure p(n+1) as an unknown variable. We apply it to a fourth order accurate staggered mesh compact difference scheme, simulate the driven flow in a square cavity with Re = 5000 and 10000.
文摘(1) A staggered mesh compact difference scheme is presented for solving the unsteady viscous incompressible Navier-Stokes equations. It is fourth order accurate both in the spatial direction and in the time direction, at least third order accurate on the boundary; (2) Describe a pressure-Poisson-equation that is equivalent to the discrete continuity equation provided the discrete momentum equations remain. The discrete continuity equation may have derivative boundary conditions,e.g., the compact difference scheme; (3) A new ADI iterative method is proposed.The pressure-Poisson-equation is in the discrete form. It is difficult to be solved with a usual ADI method. We translate it to be tridiagonal in each spatial direction of each step of the ADI iterations, then add a pseudo time term to get a tridiagonal equation which is easily to be solved; (4) The driven flow in a square cavity with Re = 10000 is simulated numerically.
文摘为研究飞秒脉冲激光冲击强化中等离子体压力时空演化规律,利用考虑电子态密度(DOS)效应的模型计算了电子热容和电声耦合系数随电子温度的演化规律,并与采用QEOS(quotidian equation of state)模型计算结果进行了对比;提出DOS飞秒脉冲激光冲击强化模型,计算得到电子温度、晶格温度、等离子体羽位置时间演化规律和等离子体压力时空演化规律,并与QEOS飞秒脉冲激光冲击强化模型结果进行了对比。结果表明:DOS飞秒脉冲激光冲击强化模型计算得到的等离子体羽位置随时间的演化规律与实验结果吻合程度更好;增加激光能量或功率密度、考虑电子DOS效应会增加电子、晶格温度和等离子体压力。