Status of the development programme for instrumentation and test techniques of the European Transonic Wind Tunnel-ETW

Feasibility studies concerned with instrumentation and test techniques for the European Transonic Wind Tunnel (ETW) are summarized. During the functional design phase of the ETW (1986-8), instrumentation and test techniques for application in cryogenic wind-tunnel operation were investigated during several feasibility studies. The studies were focused on items which might influence the design of the test section area (flow field observation, surface flow visualization, model attitude, and deformation measurement) and which might improve the test capability of the facility (engine simulation, model handling, and balance calibration). It is noted that precise knowledge of model loads, model position, model configuration, and the surrounding flow conditions is essential for testing Reynolds number effects. The standard equipment of wind tunnels (strain gauge balances, light sources, cameras, windows, etc.) is being investigated. The special operating conditions (cryogenic temperatures, limited access) require very special arrangements with innovative design and creative ideas even for these standard items