therefore, consideration of the local pressure acting on the surface of the facilities is critical in establishing safe design criteria, especially glazing bars and coverings. From the results, the wind pressure coefficients of 4 types of greenhouses built in reclaimed lands were proposed in terms of structural safety and cladding design.For CFD validations, CFD computed and WT measured results were compared with each other, and especially y+ values were mainly considered to find optimum conditions of first grid height. CFD computed y+ value almost exactly corresponded with the measured results as first grid height at 1.5 × 10-4 m. As a result, 1.5 × 10-4 m was selected for the first grid height. Computational domain and grid independence tests were also conducted to determine the domain size, the grid size. The length of upstream part was fixed at 3H, and the length of the side and the upper part was determined to be 5H and 5H, respectively. The length of downstream was determined to be 15H because the CFD model accurately predicted 10H above. The accuracy of the CFD model improved as the grid size decreased. The grid size was designed as 1.0 × 10-2 m based on a grid independence test. From a given standard, an appropriate turbulence model was selected according to the wind direction and the type and the environmental conditions of greenhouse. SST k-ω model was determined as a turbulence model for CFD validation because the statistical indices in SST k-ω model were generally higher than that in other turbulence models. Finally, the simulated and measured wind pressure coefficients were compared using statistical indices. The CFD validation model made accurate predictions under all experimental conditions. It was determined that the CFD validation model was appropriate for estimating the wind pressure coefficient.
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Evaluation of Wind Pressure Coefficients of Greenhouses using Wind Tunnel Test and Numerical Model
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