Mesoscale Numerical Simulation Based On WRF-LES Model

The rapid development of China's civil aviation in recent years put forward new and higher requirements to civil aviation meteorological forecast service. Numerical weather prediction can solve a series of objective questions such as the shortage of the meteorological observation equipment and provide more support to the weather research and forecast department at the same time, which makes it as an effective measure to improve the civil aviation meteorological services and provide strong support for the development of civil aviation.WRF(the Weather Research and Forecasting Model) has become the main numerical prediction research tool and platform. Large eddy simulation is one of the main means of fluid simulation, in meteorological research, the basic idea of LES has been widely adopted. The basic thoughts of large eddy simulation can better overcome the problem that the amount of calculation in the direct numerical simulation is in too huge. At the same time, lots of characteristic of WRF model allows it to be as the stable platform to run the large eddy simulation and provides a convenient conditions. A combination of them makes the micro-scale numerical simulation possible at the current calculation level.In order to further strengthen the downscaling numerical simulation, this research studied the construction of LES simulation of the necessary conditions; it probed into the feasibility of constructing LES under the WRF model, put forward the plan, and designed the corresponding experiment. Experimented many times, we made the model can be able to stable operated eventually, and the simulation results were well verified and analyzed; according to the specific problems in those experiments, it puts forward the corresponding answer in theory and basis.The experimental results of this study show that it is feasible to run LES in WRF model. In certain weather conditions, WRF- LES simulation can run steady for a period of time, and the simulation results is effective, which means it can correctly reflect the changes of meteorological factors(especially the velocity field) in certain local area.