The history of the European Transonic Wind-tunnel is briefly described.

After a discussion of the tunnel specifications and performance, a general description of the facility is provided.

The results of an investigation into the expected future use of the tunnel are summarised.

Information on the pilot tunnel PETW is presented, as well as some results on flow quality obtained in an aerodynamic test rig.

Finally, some reference is made to a supporting programme on cryogenic technology.

The governing differential equations of motion for flexural vibrations of a doubly curved sandwich panel consisting of stiff elastic face layers sandwiching soft viscoelastic core have been derived, considering extension and bending deformations of the face layers and shear deformations of the core, using variational principles. Solution for panel with simply supported edges is assumed in series summation form and the correspondence principle of linear viscoelasticity is applied for evaluation of resonance frequencies and associated system loss factors. The effects of variations of geometrical and material parameters on the resonance frequencies and associated system loss factors are reported.

A simplified kinetic theory of turbulence originally proposed by P. M. Chung has been modified and applied to the problem of non-uniform grid turbulence with no velocity gradients. Preliminary comparison to the experimental results of Gilbert shows good qualitative agreement. The theory contends that shear stresses induced by local drift velocities maintain the anisotropic nature of the turbulent profiles. Both theory and experiment indicate that the integral length scale is comparatively uniform across the flow.

The interaction of an incident oblique shock wave with the turbulent boundary layer with suction is investigated. Wall streamline and schlieren photograph visualisations as well as the pressure measurements on the wall are made. Boundary layer surveys with pressure probes and hot-wire probes are also done. The suction downstream of the interaction almost nullifies the shock reflection while the higher suction up and downstream of the interaction results in a reflection similar to that in inviscid flow.