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This paper presents results of an analytical and experimental investigation aimed at describing the turbulent momentum transfer mechanism in the separated-flow region of a rectangular cavity facing an oncoming turbulent boundary layer. A flow model of the mixing region in the slot postulated on the basis of eddy diffusion in free jets gives values of velocities and drag in good agreement with the measurements. The results further point to the significant effects exerted by the oncoming boundary layer on transfer rates from the slot. Flow-visualization pictures show some interesting vortex patterns inside the cavity when height-to-width ratio is varied between values of 1 and 3.

An experimental and analytical study is presented in this paper describing heat transfer in the region of separated flow over a two-dimensional rectangular cavity (of variable depth-width ratios) facing an oncoming turbulent boundary layer of variable thickness. The analysis, based on a prescription of eddy diffusion in the mixing region, predicts a heat transfer correlation, in terms of the foregoing variables, resulting in good agreement with the data. Experiments were performed with conditions of uniform temperature and uniform heat flux at the cavity walls and revealed no substantial difference between the two methods on the final correlation.

The role of eddy diffusion of mass (water vapor) and momentum was investigated in a specially devised wetted-wall channel in which the rippling of the liquid film was eliminated.The experimental measurements of the turbulent exchange coefficients for mass and momentum transport were carried out in a fully developed turbulent flow of air within the range of Reynolds numbers of 8,000 to 160,000. A correlation with Reynolds number revealed an approximately linear relationship of the eddy diffusivities to Reynolds number @quation (4)]. From the hot-wire measurements it was found that within the main portion of the turbulent core eddy diffusivities remained fairly constant.

The paper describes an analytical and experimental study of the effects of fluid injection on heat transfer in laminar air flow over a long square cavity. The Reynolds number (based on cavity width) ranged in value from 10 to 1000. The injection (of air) at the cavity wall was varied in velocity from 0 to 5 percent of the main stream. The results indicate the greatest reduction in heat transfer to be occurring at the reattachment point. An expression is suggested for predicting the approximate reduction in heat-transfer rate from the entire cavity surface.