采用周期入流边界,在展向等间距网格系统中对平板湍流边界层(驱动单元)进行LES模拟,并将顺压力梯度引入流体控制方程以维持湍流边界层厚度的稳定。记录驱动单元脉动时程并将其引入虚拟模拟网格系统(验证单元)以研究LES脉动入口方法的适用性。数值结果表明,采用周期入流边界可成功实现脉动输入,边界层在顺压力梯度下的自保持性良好;脉动入流特性在驱动单元内保持良好,可满足工程需求;顺流向平均流速剖面以及湍流强度剖面均满足低湍流度下的风场特性,数值结果可为我国B类地貌下抗风研究采用。
Using periodic boundary condition,a flat plate turbulent boundary layer(Driver section) is simulated by LES(Large Eddy Simulation)in a spanwise uniform grid system.Constant streamwise pressure gradient is introduced to NS equation to keep boundary layer thickness constant.Velocity and pressure time history in driver section are recorded and introduced as the inflow condition for a virtual building simulation section(Validation section),to research the applicability of this turbulent inflow.Satisfied numerical result of turbulent inflow is drawn from driver section,and streamwise velocity profile is well preserved by the pressure gradient,Inflow properties is also well preserved in Validation section.Inflow time history holds some of the properties of near ground wind field,and the method presented in this paper can be a reference for wind resistant research in open area.