基于界面移动理论的导线覆冰过程分析

Physical Process of Icing on Fixed Wires by Interface Movement Theory

导线表面覆冰为一个准平衡过程,根据覆冰过程固液界面移动理论建立了导线表面覆冰的增长模型,运用欧拉-欧拉法得出液滴在导线表面的碰撞系数,并考虑覆冰过程中粗糙表面效应对对流传热系数的影响,根据方程计算出导线表面覆冰厚度在不同参数下随时间的变化规律。未考虑在湿增长过程中覆冰表面水膜由于受重力及风的剪切力作用而在冰面不规则的运动。数值模拟显示:水膜随着覆冰的进行会达到一个最大厚度,水膜由于外力作用而产生的扰动对于覆冰厚度的影响可以忽略不计;导线覆冰主要集中在迎风面,沿迎风面两边覆冰厚度逐渐减小。

Icing on wires is a quasi-equilibrium process. We presented a phase change heat transfer in the processes of icing. Considering the roughness effects of surface, heat conductions in the ice and unfrozen water layers were solved with mass conservation equation, then a simplified two phase Euler model was applied in iced conductors, and the Euler method was used to calculate the local collection coefficient of iced conductor. Considering the influence of energy input from the wires on the thickness of ice and films, we did not consider the irregular movement of water film due to gravity and wind shear forces. Numerical simulation shows that water film has a maximum thickness. Due to the external force, disturbance of the water film on the conductor occurs, the influence of the disturbance on the icing thickness is negligible, and icing is concentrated in the windward. As the angle increases, the ice thickness decreases on fixed wires.