Development of High Speed Low Noise Wind Tunnel and Multipurpose Nozzles

In order to predict the aerodynamic noise of actual railway train, it is important to carry out wind tunnel test as same speed as actual railway train. Therefore, we developed “High speed low noise wind tunnel”. This wind tunnel has mainly three features. The first feature is high-speed wind velocity with low background noise. The second feature is precise aerodynamic noise measurement by wind temperature control. The last feature is that this wind tunnel nozzle is exchangeable to 4 type multipurpose nozzles. These nozzles can provide with precise aerodynamic noise measurement and crosswind assessment, and testing of rotating machinery. And, we confirmed that the velocity uniformity and turbulence level was achieved target performance regardless of aspect ratio of nozzle outlet.