Abstract:This paper was conducted to predict the turbulence structure and sheltering effect behind porous fences in open storage piles. The numerical simulation of the three dimensional static flow field was performed applying the standard k-ε turbulence model; the airflow characteristics and the shear stress distribution on the windward side, flat top surface and leeward side of a typical prismatic material stack were analyzed; and the distribution of the aerodynamic structure of each surface of the storage pile was revealed based on the data of flow field for the porous fence with different porosity. Results indicated that the shear force on the flat top surface increased with increasing porosity, exhibited litter change with unfenced conditions. Regarding the windward side of the storage piles, a re-circulating flow in the region between the fence and the pile at low porosities and the shear force acted downward along the windward face, but rather, the shear force acted upward along the windward side at high porosities. Since the leeward side was always in the backflow region, the shear force on the prismatic leeside changed little with increasing porosity. The numerical predictions showed the porous fence with porosity between 0.2and 0.4was found to be the optimum. Through the aerodynamic simulation of each surface of the storage pile, the computation distortion caused by vector offset out of different directions of the shear force can be avoided.