Speed upwind and downwind of a single plant

To evaluate difference in windbreak effect in a single plant with different morphology, horizontal wind speeds upwind and downwind of five single plants with different morphology (a slender flexible plant model, a flexible plant model with large upper part and small lower part, two tree-like rigid plant models and a rigid round stick model) were measured under three inflow wind speeds in a wind tunnel. The inflow wind speed was found to have significant effect on relative wind speed recovery curve on leeward side of flexible plants, but had little effect on rigid plant models. Average windbreak effect and protective distance of tree-like rigid plants were found to be larger than flexible plants at 0.5 h height. Variation in frontal width of plant with height was found to be an important factor for wind speed reduction at different heights.