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The problem of finite-amplitude deflections of a thin, elastic, shallow arch subject to uniform normal pressure is investigated. A COMPOSITE- MATERIAL ARCH IS INVESTIGATED WHEREIN CLOSELY SPACED GLASS REINFORCING ELEMENTS IN THE FORM OF EXTREMELY SMALL DIAMETER RODS ARE ORIENTED NORMAL TO THE ARCH MIDDLE SURFACE AND BONDED INTO AN EPOXY MATRIX. Transverse shear and transverse normal stress effects are included, as well as initial geometric imperfections in the structure. The governing equations are derived and solved by several approximate techniques to yield load-deflection characteristics from which buckling loads are obtained. The analytical results are confirmed through a series of experiments conducted on such arches.

The feasibility of Rankine-cycle space power systems incorporating nonequilibrium MHD generators was studied. The major effort was devoted to ascertaining the behavior of a large generator, which was designed in 1965 and first operated early in 1966. (Author)

The finite element method was applied to a class of initial-boundary-value problems that are commonly referred to as diffusion-convection problems. Coupled convective and conductive heat transfer with prescribed fluid velocities were studied using a Galerkin procedure in concert with an isoparametric finite element formulation that is applicable to both solid and fluid regions. Several approaches for treating the unsymmetric convective terms in the governing matrix equation were investigated; the most promising appears to be a polar decomposition and initial flux approach. A number of combined convection-conduction problems of heat transfer were investigated numerically in order to illustrate accuracy of the method and to demonstrate flaws in current analytical practice. (Author)

One of the major potential loss mechanisms for magnetogasdynamic generators operating at high Hall parameters is that of eddy currents in the entrance and exit regions of the generator. An experiment was designed to test the concept of fluid injection as a means of suppressing the exit current loops. Theoretical studies indicate that if sufficiently small droplets on the order of 5 to 30 microns in diameter are introduced into the plasma flow, they would be very effective in quenching the electrical conductivity of the exit region through the mechanism of electron and ion capture. An experiment on a subsonic MGD channel employing axial injection of fine water jets did not result in a rise in open circuit voltage which could be positively attributed to the water injection. It is tentatively concluded that the water jets did not break up into sufficiently small droplets to quench the electrical conductivity in the exit region. (Author)