An Icing Conductor Model Based On Meteorological Parameters And Its Verification

By using the daily icing data of Erlangshan Mountain in Sichuan Province during the2001-2009winter season provided by Southwest Electric Power Design Institute and the related meteorological data over the same period, the methods of correlation analysis, regression analysis and discriminatory analysis are used to study the meteorological factors and icing index associated with the icing over the Erlangshan Mountains. The main conclusions are as follows:(1) From the view of physical concept, we study the microscopic formation process of the conductor icing growth by using the fluid mechanics and thermodynamic principles, and the constructed icing theory models of rime icing and glaze icing are built. And then we analyze the effect factors of icing.(2) The relationships between the icing thickness and some meteorological factors are analyzed. It is found that the icing increase is not well related to an individual meteorological factor, so the simple using of meteorological factors can’t meet the requirements of the models. It is necessary that some physical indexes are found by using the constructed icing theory model.(3)According to the constructed icing theory model, the main influence of icing thickness is liquid water content and its transport index. However, there is not the observational data in the common weather station. We use two indirect methods to estimate liquid water content:(a) Linear relationship between the water vapor content and liquid water content,(b) Transformational relation between the visibility and liquid water content. Further we analyze the relationship between liquid water content and the icing growth index.(4) It is found that the daily icing growth index or the daily icing growth efficiency index is not well related to the related meteorological factors. Conductor icing is a cumulative process that the result of meteorological factors accumulate. So it is necessary that we consider the entire icing thickness in growth process and eliminate the effect of random factors to find the relationship between the icing growth and meteorological factors.(5) The icing theory model is changed by two different methods to estimate liquid water content. Through the correlation analysis between the icing process efficiency index and corresponding meteorological index, a conductor icing model is built according to the parameters of conventional meteorological observations including temperature, water vapor content/visibility, wind speed and wind direction.(6) The icing start and end time are analyzed by using Fisher discriminate analysis. We choose the main effect factors and built the discriminate functions about the icing start and end time through analyzing different meteorological factors at the different time.