在亚临界区高雷诺数Re=1.4×105下，采用脱体涡模拟结合湍流分离的方法对弱电解质中电磁力作用下湍流边界层分离圆柱绕流场及其升(阻)力特性进行了数值模拟和分析.结果表明，电磁力可以提高圆柱体湍流边界层内的流体动能，延缓圆柱体湍流边界层的流动分离，减弱圆柱体湍流绕流场中在流向和展向上大尺度漩涡的强度，减小圆柱体阻力时均值及其升力脉动幅值.当电磁力作用参数大于某个临界值后，湍流边界层流动分离消失，在圆柱体尾部产生射流现象，从而电磁力对圆柱体产生净推力作用，出现负阻力现象，而且升力脉动幅值接近于零，出现圆柱体升力消失现象.%A detached eddy simulation method with the turbulent separation is presented to simulate and analyze the charac-teristics for the flow around a circular cylinder with a turbulent boundary layer separation and its lift/drag coefficients in a weakly conductive fluid at a high subcritical Reynolds number 1.4 × 105 under an electromagnetic force. The results show that the electromagnetic force can increase the fluid kinetic energy near the turbulent boundary layer, delay the turbulent boundary layer separation of the flow around the circular cylinder, and weaken the intensity of the large-scale eddy in the turbulent flow around the circular cylinder in the streamwise and spanwise directions, reduce the time-average drag, and inhibit the lift fluctuation amplitude on the circular cylinder. Moreover, after the electromag-netic force parameter reaches a certain critical value, the turbulent boundary layer separation disappears and the jet phenomenon appears in the wake of the circular cylinder, so that the electromagnetic force produces the thrust action on the circular cylinder and the negative drag occurs, and the lift fluctuation amplitude declines to almost zero and the lift phenomenon on the circular cylinder disappears.
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