Linearized solutions for the flow field of a rotating blade row in an infinitely long annular duct are reviewed. An isolated rotor is assumed to operate in a uniform axial flow so that the disturbance field is steady in a blade fixed co-ordinate system. Both three-dimensional and compressibility effects are included, but attention is confined to subsonic flows. Previously published source-flow solutions omitted a term which affected the thickness part of the rotor flow field constructed from them. Corrected source and rotor-thickness solutions are given, and then the source or monopole solution is used to form a pressure dipole solution. The rotor-loading contribution to the flow field is found by superposition of the revised dipole solutions. The present version of the dipole representation of the steady-loading field is shown to be equivalent to an existing vortex representation, but different from an existing dipole representation. The behaviour of the blade-surface pressure and velocity distributions is described for both the thickness and loading cases. Sample numerical evaluations of the surface quantities are presented.

The steady, incompressible, isothermal, developing flow in a square-section curved duct with smooth walls has been investigated. The 40 × 40 mm duct had a radius ratio of 2·3 with long upstream and downstream straight ducts attached. Measurements of the longitudinal and radial components of mean velocity, and corresponding components of the Reynolds-stress tensor, were obtained with a laser-Doppler anemometer at a Reynolds number of 4 × 104 and in various cross-stream planes. The secondary mean velocities, driven mainly by the pressure field, attain values up to 28% of the bulk velocity and are largely responsible for the convection of Reynolds stresses in the cross-stream plane. Production of turbulent kinetic energy predominates close to the outer-radius wall and regions with negative contributions to the production exist. Thus, at a bend angle of 90° and near the inner-radius wall, $\overline{u_{\theta}u_r}\partial U_{\theta}/\partial r$ is positive and represents a negative contribution to the generation of turbulent kinetic energy.

In spite of the complex mean flow and Reynolds stress distributions, the cross-stream flow is controlled mainly by the centrifugal force, radial pressure gradient imbalance. As a consequence, calculated mean velocity results obtained from the solution of elliptic differential equations in finite difference form and incorporating a two-equation turbulence model are not strongly dependent on the model; numerical errors are of greater importance.

The paper presents a theoretical and experimental study of natural convection in a horizontal cavity which communicates laterally with a large reservoir. The cavity walls and the reservoir are at different temperatures. It is shown theoretically that the flow consists of a horizontal counterflow which penetrates the cavity over a distinct length. The penetration length is shown to be proportional to the cavity height and to the square root of the Rayleigh number based on cavity height and cavity-reservoir temperature difference. The validity of the theory is demonstrated on the basis of a flow visualization experiment. It is shown also that the Nusselt number for cavity-reservoir heat exchange is proportional to the square root of the Rayleigh number, and is relatively insensitive to the Prandtl number in the Pr range 0·7 to ∞. The energy-engineering applications of the lateral penetration flow are discussed.

An experimental study of the three-dimensional turbulent boundary layer on a body of revolution is reported. The data correspond to axisymmetric flow as well as the flow at an angle of incidence of 15°, and include surface pressure distributions and the distribution of the magnitude and orientation of the velocity vector in the boundary layer. The results clearly exhibit most of the complexities encountered in practical three-dimensional boundary-layer flows, such as viscid-inviscid interaction, reversal of cross-flow, open separation and onset of longitudinal vortices. Major implications of these results on the development of computation procedures are discussed.