풍력자원지도 작성시 바람장의 대칭성을 이용한 전산유체역학 수렴가속화

Convergence Acceleration of CFD Using Wind Field Symmetry for Wind Resource Mapping

A considerable computation time is required to produce a wind resource map since numerical analyses of computational fluid dynamics on a number of wind directional sectors are needed to be performed. In conventional numerical analysis, a wind speed profile of the atmospheric boundary layer introduced from the far upstream is assumed as an initial condition. In the present study, a reconfiguration method of initial conditions was applied by mirroring the converged solution with regards to 180-degree opposite wind direction, taking the symmetry of wind flow field and topography into consideration. The present study performed a wind resource mapping case study for an island area considering 12 wind directional sectors using Wind Sim software with 3 million grid cells and verified a reduction of computation time by approximately 50% after applying there configured initial conditions. If the proposed method was extensively applied to all wind directional sectors, a total computation time was reduced by approximately 25% when applying existing methods to six wind directional sectors and the reconfiguration method to the other six wind directional sectors. Thus, the proposed method is expected to contribute to the reduction time of project schedule when wind resource assessment is performed in the future.