| Summary: | 碩士 === 國立臺北科技大學 === 冷凍空調工程系所 === 98 === This study investigates the storm-resistant louver in a variety of outside air wind speed, rainfall and air flow conditions of the performance and flow field structure. Computational fluid dynamics software (Fluent) was used to simulate a three dimensional channel of storm-resistant louver in steady state, assuming incompressible fluid. Water penetration effectiveness and pressure performance of various louver and drainable blade parameters were investigated for different air velocity. The numerical simulation was verified by experimental data of pressure drops, and reasonable flow field structure. Finite volume method with hexahedron grids were used in discretizing the governingcontrol equations, and solved with SIMPLEC algorithm and the κ-ε turbulent model. The discrete phase model (DPM) was used in the simulation of raindrop flowing path and water penetration effectiveness analysis, and rainfall rate of 76mm/h was assumed. The simulation result revealed that drainable blade can affect the internal flow field distribution, inappropriate position of the blade results in vortexes generation, which increases the pressure drop. Because the droplets flow route change make it due to inertia force along the tangent hit the wall surface,therefore may set The simulation showed that the drainable blade shoud be located at the extruding curve to prevent the raindrops passed the curve tangentially by inertia force. Number of curves should be reduced to reduce pressure drop. Number of the drainable blades is as important as the position of the blade. The flow channel cross-section should be as smooth as possible and prevent sharp variation of cross-sectional area which would generate vortexes and increase pressure drop. From a series of simulations, an improved storm resistant louver was proposed. It has better water penetration effectiveness, lower pressure drop, and greater channel contraction ratio.
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