A suction-type, continuous-operation supersonic (up to Mach 1.8) wind tunnel for investigations into subsonic and supersonic air fl ow around twodimensional models. Also for analysis of the profi le of the tunnel.
Key features
• A suction-type continuous-operation supersonic wind tunnel for investigations into two-dimensional air fl ow around models for nominal air speeds up to Mach 1.8
• Includes high-quality optical glass windows in the working section, suitable for use with an optional Schlieren system
• Includes a selection of models for two-dimensional fl ow experiments and an encoder for feedback of model angle
• Supplied with a multi-pressure display unit and calibrated pressure sensors to show pressures relative to atmosphere.
• Includes a vacuum pump with remote control for ease of use
• Works with TecQuipment’s Versatile Data Acquisition System (VDAS®) for automatic data acquisition
Description
A suction-type continuous-operation supersonic wind tunnel for investigations into subsonic and supersonic air fl ow. It also allows students to study air fl ow in two dimensions around aerodynamic models.
An instrument frame (supplied) holds a remote-control unit that controls a high-capacity vacuum pump (supplied). 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. This is useful for startup and shutdown and for subsonic tests.
The working section of the wind tunnel is a convergentdivergent 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 diff erent shaped liners.
A selection of models are included with the equipment (one has pressure tappings) for experiments in twodimensional fl ow. These fi t in the ‘portal’ of the working section, fl ush to both windows. A geared mechanism allows students to adjust the incidence angle of the models. An encoder works with the optional VDAS to measure the model angle.
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.
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.
The equipment works with TecQuipment’s optional Versatile Data Acquisition System (VDAS®) and can quickly and conveniently connect to a frame-mounting interface unit (VDAS-F, not included). Using VDAS® enables accurate real-time data capture, monitoring, display, calculation and charting of all relevant parameters on a suitable computer (computer not included).
The wind tunnel includes transparent windows in the working section. These are high-quality optical glass suitable for use with the optional Schlieren Apparatus (AF302a, available separately) enabling display and recording of images of high-speed flow.
Learning Outcomes
• Pressure distribution along a convergent/divergent (Laval) nozzle with subsonic and supersonic air flow
• Comparison of theoretical and actual pressure distributions
• Comparison of actual and theoretical area ratios of a nozzle at supersonic air velocities (Mach numbers)
• Pressures around a two-dimensional model in subsonic and supersonic flow conditions, at different angles of incidence
• Lift coeffi cients for aerodynamic models in supersonic flow
• Shock waves and expansion patterns around a twodimensional model in supersonic flow conditions (when used with the optional Schlieren apparatus).
Essential Ancillary
• Versatile Data Acquisition System - Frame-mounted version (VDAS-F)
Recommended Ancillary
• Schlieren Apparatus AF302a
