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通过求解雷诺平均Navier-Stokes方程,采用SST两方程湍流模型,模拟具有螺旋桨吹气作用的飞艇绕流流场。采用压力盘方法模拟螺旋桨滑流流动。在驻点引射飞艇外表面不同位置添加螺旋桨进行吹气。数值模拟结果显示,在开放边界外部流动情况下,螺旋桨只具吹气作用。螺旋桨吹气可以将分离漩涡吹离物面,减小绕流的压差阻力。在前缘吸力峰之后的位置,是螺旋桨吹气的最佳位置。在这一位置之后,螺旋桨吹气作用于物体表面的区域越宽,压差阻力系数减小的越多。螺旋桨作用于前缘吸力峰之前会导致摩擦阻力系数增大。螺旋桨的直径越大吹气减阻效果越好。增加螺旋桨吹气强度,阻力系数降低的越多。沿飞艇周向间隔添加螺旋桨的结果显示,螺旋桨越密集,吹气减阻效果越好。
By solving the Reynolds-averaged Navier-Stokes equation and using the SST two-equation turbulence model, the flow around the airship with propeller blowing is simulated. Pressure disk method was used to simulate the propeller slipstream flow. Addition of a propeller at different positions on the outer surface of the airship in the stagnation point for blowing air. The numerical simulation results show that the propeller only blows when the flow is outside the open boundary. The propeller blows the separated vortex away from the object surface and reduces the pressure drop resistance around the flow. The position behind the leading edge suction peak is the best place for the propeller to blow. After this position, the wider the propeller blows on the surface of the object, the more the drag coefficient decreases. The effect of the propeller on the suction edge of the leading edge results in an increase of the frictional resistance coefficient. The larger the diameter of the propeller, the better the drag reduction effect. Increase the propeller blow strength, drag coefficient decreases more. The results of adding propellers at intervals along the airship show that the more dense the propeller, the better the air blowing drag reduction effect.