基于改进Messinger覆冰模型导线防冰临界电流计算及其影响因素分析

摘要

This paper improves the Messinger icing model by establishing the water film flow model on conductor surface based on the water film flowing on conductor surface during the current anti-icing periods, to obtain the conductor anti-icing critical current under different icing meteorological conditions. The calculation methods about the local collision coefficient (LCC) of super-cooled water droplets, the local heat transfer coefficient (LHTC) on conductor surface and the local freezing coefficient (LFC) of liquid water on conductor surface are determined. It is the first time to calculate the LHTC and LFC on conductor surface. Moreover, the automatic computation of conductor anti-icing critical current is achieved based on the calculated LFC. The results show that the LCC, LHTC and LFC on conductor surface reach their maximum values in the position of conductor stagnation point, where the LFC decreases with increasing the conductor current. Wind speed and temperature are the main factors affecting the anti-icing critical current, while the water content and the diameter size of droplet have little effects on the critical current.%为了得到不同覆冰气象条件下导线防冰临界电流，基于电流防冰时导线表面水膜流动，建立导线表面水膜流动模型对 Messinger 覆冰模型进行改进，确定了过冷水滴局部撞击系数（LCC）、导线表面局部对流换热系数（LHTC）与导线表面液态水局部冻结系数（LFC）计算方法。首次计算导线表面LHTC与LFC，并基于LFC计算结果，实现了导线防冰临界电流自动计算。计算结果表明：导线表面 LCC、LHTC 和 LFC 在导线驻点位置达到最大值，其中 LFC 随电流增大而减小；风速、温度是影响防冰临界电流的主要因素，含水量与水滴直径大小对临界电流没有明显影响。