为了解展向存在匀速流动时湍流槽道流动的特性,应用直接数值模拟方法研究了壁面的展向运动对湍流槽道流动的影响.采用标准谱方法对固定质量流率条件下,上壁面展向运动速度分别等于零、流向流量平均速度以及两倍于流向流量平均速度等3种情况进行了直接数值模拟.结果表明,壁面的展向运动会导致表面摩擦力的增大,二阶湍流统计量诸如均方根速度脉动、雷诺剪切应力和均方根涡量脉动等都会随着壁面展向运动速度的增大而显著增长,同时,槽道截面上的均方根速度脉动也变得更均匀.
The influence of spanwise moving wall on turbulent channel flows is investigated using direct numerical simulations (DNS) , which in order to know the characteristics of turbulent channel flows when existing spanwise moving velocity. The DNS is performed using the standard spectral method. Three cases with the spanwise wall moving velocity which equals 0, bulk flow velocity and double bulk flow velocity are simulated at constant mass flow rate. The results show that spanwise moving wall induce the skin friction increasing. The second-order turbulence statistics such as root-mean-square velocity fluctuations, Reynolds shear stress and root-mean-square vortieity fluctuations are substantial increase with spanwise velocity increasing. It is also observed that the root-mean-square velocity fluctuations become more even across the channel with spanwise velocity increasing.