CFD를 통한 차양의 자연환기 성능 향상에 관한 연구

In the present study, we consider an overhang as the building texture that is mostly used for preventing from the sun light and the rain drop. We investigate the effect of the overhang on ventilation performance considering environmental conditions such as wind speeds and directions. We used a commercial CFD program STAR-CCM+ for simulations of three-dimensional unsteady turbulent flows over an idealized building with the overhang. Parametric studies were systematically performed for four different lengths of overhang as well as nine different wind conditions. Computational results showed that regardless of wind speeds, the overhang in windward direction enhanced the ventilation performance while the ventilation rate was decreased in other wind directions. This is related to the fact that for the windward cases the overhang induces wake flows where a strong flow separation was observed near the tip of the overhang promotes turbulent fluctuations at the door yielding to increased ventilation rates. However, for other wind directions, the flow separation near the edges of the building disturbed the turbulent eddy penetration into the interior of the building.