薄覆冰导线气动力特性风洞试验研究

薄覆冰舞动是一种常见而又难以用传统理论来解释的现象，需采用风洞试验对薄覆冰导线的气动力特性进行研究。根据某工程舞动现场调查结果，设计了3种覆冰厚度导线模型做风洞试验，利用六分量高频天平测得在2种不同流场中准椭圆形覆冰导线模型的平均气动力。通过平均气动力系数的对比分析结果，指出Den Hartog系数不适合用来分析薄覆冰导线的舞动特性。在Den Hartog对导线舞动定性分析的理论基础上，提出了2个发生舞动的必要条件。通过试验结果的分析，得到薄覆冰导线可能发生驰振不稳定的风向角。

Wind Tunnel Test on Aerodynamic Characteristic of Conductor with Thin Ice Accretions

Galloping of conductor with thin ice accretions is a common but unexplained phenomenon. Wind tunnel tests are needed to study the aerodynamic characteristics of conductors with thin ice accretions. Based on the galloping investigation of real transmission lines with ice, three conductor models with different ice thickness are designed and tested in the wind tunnel. The average aerodynamics of quasi-oval shape iced conductor models in two different flow fields are measured by using six-component high-frequency balance. Through the comparison and analysis of average aerodynamic coefficients, Den Hartog coefficient is found not suitable for the analysis on thin ice wire. On the basis of qualitative explanation of Den Hartog to galloping, two necessary conditions of galloping are proposed. Through the analysis of test results, the wind attack angle has been acquired when the conductor gallops with thin ice accretions.