Supersonic Wind Tunnel

A suction-type continuous-operation supersonic wind tunnel for investigations into subsonic and supersonic air flow. The pump creates low pressure downstream of the working section to draw air into the wind tunnel. A bypass duct, with a hand-operated valve, allows the operator to reduce the air flow through the working section, without disturbing the quality of the main air flow. It also allows students to study air flow in two dimensions around aerodynamic models. The working section of the wind tunnel is a convergent divergent nozzle with a removable top part (‘liner’). The shape of the liner controls the maximum air velocity at the divergent part of the working section. Included are three different shaped liners. An instrument frame (supplied) holds a remote-control unit that controls a high-capacity vacuum pump (supplied). This is useful for startup and shutdown and for subsonic tests.  A selection of models are included with the equipment (one has pressure tappings) for experiments in two dimensional flow. These fit in the ‘portal’ of the working section, flush to both windows. A geared mechanism allows students to adjust the incidence angle of the models.

An analogue pressure gauge measures and displays the suction of the pump (tunnel reference pressure). This pressure line also connects to the multi-pressure display for data acquisition. Pressure tappings along the working section connect to a ‘mimic’ panel and multi-pressure display unit in the instrument frame. The display unit shows the pressures at the tappings. The display includes calibrated pressure sensors to measure pressures relative to atmosphere. It also shows the pressures on one of the models.