Abstract: The grid independence of the flow field in Model I has been analyzed and the simulation results show that the error rate of calculation result is the lowest when the relevance of the grid division is 70 and the relevance center is fine.The computing time is about 3h,thus acceptable.Therefore,to minimize the error,the grid division method is adopted to compute the simulating flow fields of Model Ⅰand Ⅱ.When compared with the results of vehicle tests,the final results of this research show that the two models can concentrate wind energy and improve the energy density effectively.In the installation section of wind turbine,the point whose relative error between simulated values and measured values is less than 5 percent,10 percent and 20 percent accounting for 41.67 percent,83.33 percent and 91.67 percent respectively.Therefore,the result of grid independence analysis can be used for the preliminary quantitative analysis of concentration wind energy device so as to provide reference for the design of impeller installed inside the device.And the simulation and experiment both conclude that Model Ⅱ is better than Model Ⅰ.Hence the qualitative analysis of different concentration wind energy device may be carried out to optimize the contour of concentration wind energy devices by this method.