This paper extends the Wagner torsion bending theory for open section tubes to general systems of applied loading. An illustrative example is also included involving the calculation of the twisting and direct stress distribution in an axially loaded Z-section column.

Hypersonic small-disturbance theory is applied to the source flow over power-law slender bodies with conical or wedge type asymptote. The results for a point source flow with λ=2 over power-law cones of revolution show that the dominating equations in the first and second approximations are essentially the same as the ones for the parallel flow over power-law bodies of revolution. In the special case of a cone, results of a source flow and of a parallel flow are compared and it is shown that the surface pressure in a source flow at the nose is the same as the constant cone pressure in a parallel flow, but systematically decreases in the rear part. This is confirmed by comparison with a shock tunnel experiment.

A numerical method is described for predicting incompressible, attached flow round multiple-section aerofoils at high Reynolds number. Interaction between wakes and boundary layers is not accounted for, but the method is nevertheless suitable for optimisation of design in the take-off condition. The solution is obtained in three steps:

1. (i) The calculation of the outer, potential flow using a conventional Kutta condition for each aerofoil section.

2. (ii) The calculation of viscous boundary layers and wakes.

3. (iii) The combination of the inviscid and viscous solutions to effect proper matching at the edges of the boundary layers and wakes and a more accurate specification of the circulation in the inviscid flow.

Results are presented of an experimental investigation on a non-conical wing which supports an attached shock wave over a region of the leading edge near the vertex and a detached shock elsewhere. The shock detachment point is determined from planform schlieren photographs of the flow field and discrepancies are shown to exist between this and the one calculated by applying the oblique shock equations normal to the leading edge. On a physical basis, it is argued that shock detachment has to obey the two-dimensional law normal to the leading edges. From this, and from other measurements on conical wings, it is thought that the planform schlieren technique may not be particularly satisfactory for detecting shock detachment. Surface pressure distributions are presented and are explained in terms of the flow over related delta wings which are identified as a vertex delta wing and a local delta wing. The forces acting on the wing are calculated and are shown to be very close to the two-dimensional wedge values over a wide range of incidence. In particular, it is shown that this wing, compared to one which supports a fully detached shock wave, generates a higher lift/(pressure drag) ratio at a given lift coefficient.

Measurements of mean velocity and Reynolds shear stress have been made in a turbulent boundary layer downstream of a small step change in surface roughness. Upstream of the step the surface is smooth, while downstream it consists of a d-type rough wall made up by a series of two-dimensional elements of square cross section placed transversely across the flow and spaced one element width apart in the direction of the flow. The calculated mean velocity and Reynolds shear stress profiles obtained using the method of Bradshaw, Ferriss and Atwell are in good agreement with the measurements throughout the relaxation region of the layer. Well downstream the calculation method adequately reproduces the self-preserving features of a d-type rough wall.

The paper deals with the free transverse vibration and stability analysis of circular cylindrical composite panels. The panels are assumed to be composed of an arbitrary sequence of 0° and 90° layers. The non-dimensional vibration and buckling parameters are computed for simply-supported panels consisting of antisymmetric crossply graphite-epoxy laminates. The influence of the coupling between bending and extension, shear deformation, the panel curvature, and the aspect ratio are then discussed.

The paper describes the application of a recently developed numerical scheme to the computation of the flow in a curved duct. The flow situation is partially-parabolic in nature as there are significant elliptic effects, which are transmitted through the pressure field. The turbulence model used comprises two differential equations, one for the kinetic energy of turbulence and the other for its dissipation rate. It has been observed that the predictions using the new procedure agree very satisfactorily with the experimental data. Comparisons are also made with the predictions of a fully-parabolic calculation procedure.