CFD Simulation and Experimental Validation of a New Closed Circuit Wind/Water Tunnel Design

A new closed-circuit wind/water tunnel to support flow visualization research was designed and constructed at The University of Aberdeen. Review of existing closed-circuit tunnel designs revealed that they are large, expensive, difficult to set up and maintain, and typically employ a single working fluid. Key objectives of the work reported here were to reduce the overall cost and size of the tunnel, facilitate the use of alternative working fluids (air or water), and provide high quality flow within the test section. Conventional design methods were used initially, and computational fluid dynamics (CFD) was then employed to simulate the flow within critical sections of the tunnel. The results from CFD played a decisive role in identifying the modifications needed to achieve the compact, cost-effective tunnel design eventually built and tested. Flow quality within the test section was established using measured velocity profiles, and these are also presented.