Numerical simulations and experiment research are both carried out to investigate the control of spanwise oscillating Lorentz forces on a turbulent channel flow.The variation of the streaks and the skin friction drag are obtained through the PIV system and the drag measurement system,respectively.The flow field in the near-wall region is shown through direct numerical simulations utilizing spectral method.The experiment results are consistent with the numerical simulation ones qualitatively,and both indicate that the streaks are tilted into the spanwise direction and the darg reduction utilizing spanwise oscillating Lorentz forces can be realized.The numerical simulation results reveal more details of the drag reduction mechanism which can be explained as the spanwise fluctuating vortices generated,from interaction between the induced longitudinal vortices and intrinsic turbulent flow in the near-wall region can make the longitudinal vortices tilted and oscillated to suppress the turbulent intensity and lead to drag reduction.%对槽道湍流的展向振荡电磁力控制进行了实验和数值研究.实验通过PIV系统和浮动床阻力测试系统记录近壁区的条带变化和壁面阻力变化.计算时,利用谱方法直接模拟电磁力控制下的近壁流场.实验和计算结果定性一致,皆表明展向振荡电磁力可以减少壁面阻力,并使条带倾斜.计算结果还进一步揭示了电磁力减阻的机理.电磁力诱导产生的流向涡与壁湍流的相互作用,在近壁处形成负的脉动展向涡,该涡将导致流向涡的倾斜和振荡,从而抑制湍流,减少壁面阻力.
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