利用2011年1月—2013年3月在贵州开展导线覆冰自动观测试验获取的观测资料,分析了覆冰过程演变及其气象条件变化特征,提出一次完整的导线覆冰过程包括覆冰开始、增长、维持、减弱、消融5个阶段,并得到覆冰过程的气象条件判别指标;基于导线覆冰理论模型的改进并结合气象条件判别,建立了基于过程判别的雨雾凇导线覆冰气象模式,应用该模式对观测获取的多个导线覆冰过程进行数值模拟检验.结果表明:模式能够模拟自然环境下覆冰的增长,并能够正确模拟出覆冰的减弱、消融,模拟过程覆冰质量变化的最大相对误差小于20%.该模式具有较完整的理论基础和计算方案,主要以常规气象观测要素为输入,能够计算输出覆冰全过程逐小时覆冰质量、覆冰厚度及覆冰密度变化,具有较大的应用前景.%Due to lack of detail observations of wire icing processes under natural environment,evolution charac-teristics of wire icing processes isn't very clear and the modeling is difficult.To solve this problem,under the support of the National Research Funds for Public Welfare,a special equipment for automatic monito-ring the mass of ice accretion on wires is successfully trial-manufactured and employed in field observation experiments carried out in Guizhou.During the field observation experiments from January 2011 to March 2013,plenty of detail observations of wire icing process are obtained,including minutely evolution of ice mass and relative meteorological elements,which provide conditions for subsequent research.Using the experiment data,evolution characteristics of wire icing processes and relative meteorological conditions are investigated.Results show that there are five different evolution phases in the whole icing process,inclu-ding beginning,growth,persistence,fading and dispelling of the ice-coat,and the judgment criteria of me-teorological conditions are found out.A numerical model describing wire icing processes caused by rime and glaze is developed and applied to simulate observed wire icing processes. Based on the theoretical model frame for wire icing which is universally accepted,and combined with the judgment criteria of meteorological conditions,a numerical model of wire icing caused by rime and glaze based on the process judgment is presented.The model adopts improved parameterization schemes and al-gorithms,including respective procedures for rime and glaze icing,and takes the mass loss due to sublima-tion and surface evaporation into account.With the in-situ meteorological data combined with the judgment criteria of meteorological conditions,the numerical model is validated by applying to simulate observed wire icing processes.Modeling results show it is able to describe correctly the whole icing process,inclu-ding growth,persistence,fading and dispelling of the ice-coat,with the maximum difference of ice-coat quality between modeling and observation less than 20%.Modeling errors come from two aspects,inclu-ding calculation errors of the model itself and errors of meteorological data input.The icing model with common meteorological elements input can be used to calculate and hourly variation of mass,thickness and density of the ice-coat,and is of practical value for application.Under the condition of inputting with mi-crophysics observations of real weather processes,the modeling result can be further improved.Further-more,taking advantage of products from a refined local numerical weather forecast model,this icing model can be applied in predicting the evolution of the ice accretion on the real power transmission lines,and has wide application prospect.
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