An implicit finite difference scheme in primitive variables is used for analysis of unsteady, laminar flow past transversely vibrating cylinders. Predictions of flow past an impulsively started cylinder and of vortex shedding from a stationary cylinder agree well with experimental data. Calculations of flow past a transversely vibrating cylinder were within the range of experimental scatter only for small vibration amplitudes. Several experimentally observed phenomena such as drag amplification and reduction in excitation lift coefficient at large vibration amplitudes were numerically predicted.

A numerical study of heat transfer in 90 deg, constant cross section curved duct, steady, laminar, flow is presented. The work is aimed primarily at characterizing the effects on heat transfer of duct geometry and entrance conditions of velocity and temperature by considering, especially, the role of secondary motions during the developing period of the flow. Calculations are based on fully elliptic forms of the transport equations governing the flow. They are of engineering value and are limited in accuracy only by the degree of computational mesh refinement. A comparison with calculations based on parabolic equations shows how the latter can lead to erroneous results for strongly curved flows. Buoyant effects are excluded from the present study so that, strictly, the results apply to heat transfer flows in the absence of gravitational forces such as arise in spacecraft.

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A model is formulated with which one may calculate the rate of disappearance of a species dissolved in fluid trapped in a microscopic cavity of a surface. The model accounts for diffusion, convection, and chemical reaction. Solutions are carried out, and a numerical example is worked out in order to show the representative time scales of these interacting processes.