The structure of shock-waves in gas mixtures is studied. The separation of component velocities and temperatures is described. Velocity overshoot is never found to exist. Other effects, namely, temperature overshoot and undershoot and velocity undershoot are shown to exist in a manner which is self-consistent with the derivation of the governing equations.

Assuming zero divergence, the equations of forced long waves in a uniformly rotating, homogeneous ocean are reduced to a single partial differential equation for the stream function. A shelf of exponential slope between a rigid continent and a sea of uniform depth is taken as a model, and certain other assumptions are made which appear physically reasonable. Calculations made on the basis of this simplified theory are in good qualitative agreement with observations of shelf waves, indicating that these waves are generated by the stress of the longshore component of the geostrophic wind.

Finite difference solutions for the time dependent equations of motion have been carried out in order to extend the range of available data on steady flow around a cylinder to larger Reynolds numbers. At the termination of the calculations for R = 40 and 200, the separation angle, the drag coefficient and the pressure and vorticity distributions around the surface of the cylinder were very close to their steady-state values. For R = 500 the separation angle and drag coefficient were very close to their steady-state values but the pressure distribution and vorticity distribution at the rear of the cylinder were still changing slightly. The results at R = 500 were found to be quite different from those at R = 200 so it is not clear how closely we approximated the steady solution for R → ∞. The forces on the cylinder due to viscous drag and due to pressure drag are found to be smaller for steady flow than for laboratory experiments where the wake is unsteady.

A linear model of the circulation of a stratified ocean, in a closed basin, driven by both wind stress and heating is presented. Particular attention is given to the interdependence of the primary features of the oceanic circulation. The upwelling process is studied in detail and it is shown that the complete determination of the mid-ocean thermocline solution depends on the upwelling in the boundary layers on the ocean basin's side walls. The morphology of the side wall boundary layers as a function of the stratification is also discussed.

The local and average mass flow rates for nearly free molecular flow through a two-dimensional slit are determined for several tank pressure ratios. The equilibrium gas in the two tanks and the container walls are assumed to be at the same temperature and the Willis iterative method with the Bhatnager-Gross-Krook model is used for the analysis. The results for an infinite pressure ratio are also presented in order to illustrate the effects of a finite pressure ratio.

It is shown that the criteria of Preston and of Patel & Head are special cases of a general Reynolds-number criterion which can be deduced as a requirement that there shall be some part of the boundary layer (in practice, the inner layer) in which the energy-containing and dissipating ranges of eddy size do not quite overlap.

The convective flow in an infinite horizontal fluid layer rotating rigidly about a normal axis is investigated for the special case of infinite Prandtl number and free boundary conditions. For slightly supercritical Rayleigh numbers the solutions of the non-linear steady-state equations are derived approximately by an amplitude expansion. A stability calculation shows that no stable steady-state convective flow exists if the Taylor number exceeds the critical value 2285.

The diffraction problem of a plane shock wave at the apex of an obtuse wedge treated by Lighthill (1950) is extended by assuming that the shock wave strikes the walls of the obtuse wedge at some finite oblique angle of incidence (not exceeding the critical angle). Transformations similar to that performed in the above-mentioned paper lead to a non-symmetrical boundary-value problem for an analytic function of a complex variable having a non-homogeneity in the form of a delta-function. It was found possible to extend, for the case considered, the method developed by Lighthill and construct the solution in almost as simple a form as given in the above-mentioned paper. The case of three-dimensional stationary flow is considered when the line of reflexion makes a finite angle with the edge of the wedge.

The measured pressure distributions over the front hemisphere of a hemispherecylinder combination placed in an aligned fields magneto-fluid dynamic flow are presented. Integration of the pressure profiles show that the form or pressure drag of the composite body first increases as the magnetic field strength increases, at a fixed flow velocity, but then decreases as the magnetic field becomes still stronger.