Design and Experimental Investigation of a Nozzle in the Test Section of a Low Speed Wind Tunnel

One of the conventional ways to increase velocity of a fluid flow is using a nozzle in stream wise. In this paper, in order to increase the flow velocity in a low speed wind tunnel, and to carry out experiments at higher velocities. An optimal nozzle profile, by considering constraints such as the nozzle inlet cross section, inlet velocity, and nozzle length has been designed using computational fluid dynamics. Design variables were the nozzle inlet cross section, outlet velocity, the turning point of the nozzle profile, the uniformity of the outlet flow and the effective length of the test section. The performance of the designed nozzle was experimentally investigated. According to the results, the velocity increased by 13 m/s and the uniformity of the flow decreased by ±1%.