Design of Mini Wind Tunnel Based on Coanda Effect

Abstract

An experimental investigation and CFD treatment were employed to design mini-wind tunnel based on Coanda effect for model tests and basic research. The inlet source flow is efficiently creating smooth steady airflow with acceptable noise, achieving the possibility of placing the test target closer to the source of flow with reasonable estimates of turbulence intensity. The design aims at achieving flow uniformity in the working section midplane, preventing separation in the contraction and minimizing the boundary–layer thickness. Intensive measurements after construction demonstrate the significance of the design process and validate the CFD predictions. The results are represented in graphic form to indicate the aspects of the contraction ratio. The numerical and experimental results show the uniformity of velocity distribution inside the working section. Tracing of separation and backflow is crucial allowing a variety of realistic demonstrations to be performed. The numerical solution provides a powerful tool to demonstrate the rate of boundary–layer growth inside the working section and validate against the empirical correlations with insignificant wall–friction drag. Assessment study to address large–scale wind tunnel based on coanda effect would be considered.