Wind tunnel test of wind pressure distribution on mutual insert multi-greenhouse roof

The distribution of wind pressure of a mutual inserted multi-greenhouse was researched comprehensively on wind angles and canopy or non-canopy on the basis of wind tunnel test. The result of test shows that wind pressure coefficient of open ventilators is distinctly bigger than the coefficient of closed ventilators and the changing scope of wind pressure coefficient is wide. As a result, the wind pressure coefficient of closed ventilators should be chosen when computing the wind pressure of greenhouse surface. The intensity and direction of air stream change when the air stream flows through the greenhouse roof. Wind pressure distribution of greenhouse with canopy is more complicated than that of non canopy. The positive and negative wind pressures appear alternately when roof of greenhouse is overlaid by canopy. For ensuring the safety of greenhouse design, the bigger wind pressure shape coefficient of two states should be chosen when the wind pressure is computed. The wind pressure shape coefficient of the two states of canopy and non-canopy should be combined when comput the mutual inserted multi-greenhouse’s wind pressure, namely, the bigger one as the warrant of greenhouse structural design should be selected.