The effect of wind barriers on airflow in a wind tunnel

Porous wind barriers are widely used and proven more efficient than solid barriers. In this study, the shelter quality of wind barriers of different porosity, row space and row number was compared based on wind-tunnel measurements. The 14 cm-high (H) scaled models of wind barriers were placed perpendicularly to the wind direction in the wind tunnel, and rough elements were placed upwind of the models to obtain a reasonable self-simulation zone and Reynolds number. The results show that the airflow field changes little in the area above one-row wind barriers. In the area below the models, the airflow field is rearranged into four energy regions. The best shelter effect achieved downwind is always obtained using a 0.35-porosity wind barrier, so we suggest the optimal porosity of 0.3–0.4 for wind barriers in sand-control engineering. The shelter effect comparison of two-row 0.35-porosity wind barriers indicates that 6 H is the optimum row space. Two-row and three-row wind barriers obviously provide better shelter than one-row barriers. Therefore, we suggest 5–7 H as the optimal row spacing for multi-row wind barriers. Our results indicated good agreement with previous studies regarding porosity, row number and row space, with some exceptions about wind barrier design regarding porosity. •We model airflow round wind barriers with varying porosity, row number and row space.•Wind barriers similar in morphology & feature to the filed ensure geometric similarity.•Sound self-simulation zone and Re value are derived using roughness in a wind tunnel.•Airflow and benefit analysis suggest 0.3–0.4 be the optimal porosity.•Benefit comparison imply 5–7 H be the optimal row space and multi-row is better.