PARAMETRIC ANALYSIS AND NUMERICAL SIMULATION OF CLOSED-CIRCUIT SMALL SIZE WIND TUNNEL FOR LOW PRESSURE AERODYNAMIC TESTINGS

Design parameters for wind tunnel facility aimed for low pressure aerodynamic testings was investigated by two dimensional numerical simulation using a Fluent software. The number of corner vanes before the contraction part showed the most noticeable changes in the flow uniformity at the test section. With 20 corner vanes, span-wise symmetry became worse as the length ratio of the contraction part decreased, while the velocity distribution exhibited the best uniformity when the length ratio was 40%. As the diverging angle of the divergent part after the fan decreased from 3 degree to 2 degree, the flow uniformity was degraded. It turned out that a density change due to the altitude change does not affect the boundary layer profile.