HIGH RESOLUTION WIND RESOURCE ASSESSMENT METHOD BASED ON COUPLING MESOSCALE MODELING WITH CFD TECHNOLOGY

Since the 80s of last century, the mesoscale simulation technology based on the atmospheric numerical model has been developing for a long time. From the last century in the 90's, some mesoscale simulation systems have been very advanced and be used all over the world. With the progress of computer science, the mesoscale simulation platform based on the atmospheric model has entered the stage of practical operation. At present, there are some main systems such as the European Centre for Medium-Range Weather Forecasts (ECMWF), the American NCEP model, Japan Meteorological Agency model, and so on. The macro wind resource assessment based on mesoscale technology has been widely used to the planning in the earlier stage of wind power projects, especially in the area that lack of wind measurement data, or difficult to measure the wind speed and direction such as open-sea area. Generally the resolution of the mesoscale simulation isn’t fine, set at “km” level. Because of gross resolution of mesoscale model, in complex terrain situatioin it can’t catch the microscale terrain effect. It is why CFD model is introduced for doing large scale high resolutioin wind resource assessment. Coupling mesoscale modeling with CFD technology allows us to consider the both effects brought by local terrain and large scale climate background. It also allows us to get high resolution reliable wind maps on the most complex terrains over large areas. At present, with the development of wind power project in China, there are more and more projects located at the complex terrain and complex environment. At the same time, since the large planned area of project, the complex mountain area, and limited number of met mast, even without met mast, in order to the reliable development of the wind power project, it is important that how to do the wind resource assessment without actual measurement wind data and other conditions such as less reliable wind data, and the met mast was not considered representative. This paper will use the atmospheric model to do mesoscale simulation calculation of wind resources, and then combine with CFD technology to downscaling computation to get high resolution wind power assessment result. Finally, in order to confirm the validity of this application in the actual project, the comparison between calculation values and measurement values is carried out. The verification result through the actual data of different met mast shows that the wind resource assessment method which combines the CFD and mesoscale technologies is reliable. The main contribution of the article is to provide the reference model and approach for regional planning and large scale wind resource assessment when there isn’t enough adequate and effective wind data.