三维旋转部件复杂表面结冰数值模拟

为模拟旋转部件复杂表面的结冰过程,开展旋转空气流场,水滴撞击,以及水膜流动结冰热力学模型研究。采用旋转坐标系进行处理,将惯性系下的周期转动边界转换为定常流动边界,求解其N-S方程,获得旋转空气流场。在此基础上,将科里奥利加速度及离心加速度引人水滴流动的控制方程,利用欧拉方法建立水滴运动撞击旋转壁面的撞击特性模型。最后,在旋转坐标系下对表面水膜的受力运动情况进行分析,建立了考虑离心力与科里奥利力影响的三维旋转表面水膜流动结冰热力学模型。以旋转圆柱为对象,进行了仿真计算,结果表明,所建立的模型对旋转部件的水滴撞击与结冰模拟是可行的,且随旋转速度的增加,水滴撞击与结冰区域的偏移更加显著。

Simulation of Ice Aceretion on Complex Suface of Rotating Component

Air flow field, droplets impingement and water film flow icing thermodynamic model arestudied to simulate ice accretion on the complex surface of rotating parls. The rotating coordinate sys.tem is adopted to deal with the problem. The periodic rotation boundary in the inertial system is con-verted into the stationary flow boundary ,and then the N-S equation is solved to obtain the rotating airflow field. On this basis ,the Coriolis acceleration and centrifugal acceleration are introduced into thegoverning equation of water droplet flow, and the Euler method is used to establish the impact characteristic model of water droplet movement hitting the rotating wall. Finally .the force of the surfacewater film is analyzed in the rotating coordinate system ,and an icing thermodynamics model for wa-ter film flow on the three-dimensional rotating surface considering the effects of centrifugal and Cori.olis forces was established. The simulation was carried out with the rotating cylinder as the object.The results show that the model established is feasible for simulating the impact and icing of waterdroplets on rotating parts, and the displacement of the impact and icing area of water droplets be.comes more signifcant as the rtation speed increases.