Utilization of Wind Tunnels for Subsonic and Transonic Flow for Aeronautical and Non-aeronautical Applications: A Review

Wind tunnels are built with a certain function in mind and a certain speed range in mind. In this paper, the utility of wind tunnels for varied flow conditions which affect forces on the objects is discussed. As time progresses, more work is being done on wind tunnels which reflects a skilful combination of technology whose roots are based on principles of wind tunnels. Facility characteristics, the principles of operation and therefore the evolution of wind tunnels came to be as they are in today’s world are reviewed. Computational analysis, design criteria and flow physics for subsonic and transonic flows are discussed in this article for closed section testing. Subsonic flow around a circular cylinder and transonic flows over a lambda wing is taken as specific cases. The developed analytical models and closed-circuit wind tunnel tests are compared to validate. The average value of drag coefficient in a circular cylinder subsonic flow indicated a 25–9% variation between the numerical models and the wind tunnel in the specific range of fluid flow (Re). The average value of pressure suction coefficient in a circular cylinder subsonic flow indicated a 27 to − 6% variation between the numerical models and the wind tunnel in the same range of fluid flow. The flow topologies measured using different turbulence models are in good agreement with the schlieren images obtained through the wind tunnel testing for a transonic flow over a lambda wing.