The effect of large density differences on film cooling effectiveness was investigated through the heat-mass transfer analogy. Experiments were performed in a wind tunnel where one of the plane walls was provided with a porous strip or a row of holes with three-diameter lateral spacing and inclined 35 deg into the main stream. Helium, CO2, or refrigerant F-12, was mixed with air either in small concentrations to approach a constant property situation or in larger concentration to produce a large density difference and injected through the porous strip or the row of holes into the mainstream. The resulting local gas concentrations were measured along the wall. The density ratio of secondary to mainstream fluid was varied between 0.75 and 4.17 for both injection systems. Local film effectiveness values were obtained at a number of positions downstream of injection and at different lateral positions. From these lateral average values could also be calculated. The following results were obtained. The heat mass-transfer analogy was verified for injection through the porous strip or through holes at conditions approaching a constant property situation. Neither the Schmidt number, nor the density ratio affects the film effectiveness for injection through a porous strip. The density ratio has a strong effect on the film effectiveness for injection through holes. The film effectiveness for injection through holes has a maximum value for a velocity ratio (injection to free stream) between 0.4 and 0.6. The center-line effectiveness increases somewhat with a decreasing ratio of boundary layer thickness to injection tube diameter.

This compilation of thermophyical and mechanical properties of certain metallic fuels is meant to be used as a common source of data in work related to the Integral Fast Reactor. Because research on these properties is an ongoing effort, this handbook must be continuously updated in order to provide the best data set to all involved in the IFR program. The use of cornmon source of properties will facilitate comparison of various analyses of fuel behavior performed within the program. It also rvill facilitate uncovering gaps and weaknesses in the data base, and thus enable better direction for future work on experimental properties work.

A laboratory study of dryout heat fluxes in particulate beds heated through the base is reported. More than two hundred experimental heat flux data points were measured. Semi-empirical correlations of the dryout heat flux data for both deep and shallow particulate beds are developed, based on flooding in countercurrent flow in deep beds and a boiling crises in shallow beds. The role of capillary forces in bed dryout is discussed and an explanation for the variation of dryout heat flux with bed height in volumetrically heated particulate beds is presented.

The growth of a solid–liquid, two-phase region during selective freezing of a dilute, eutectic-forming, salt solution over a subcooled ice slab is investigated experimentally and theoretically. The morphology of the two-phase region and the kinetics of the solid–liquid interface observed for a NaCl-H2O system are described photographically. The motion of the two-phase, liquidus front, recorded by a telescopic device that amplifies the local phenomena of the two-phase region, is presented along with the measured transient temperature distribution of the system. Based on the assumption that the solution element of the two-phase region is in local thermodynamic equilibrium with the solid phase, a similarity model is developed to predict the dependence of the freezing rate on various controlling parameters of the system. Transient heat conduction in the ice slab is also included in the model to study the effect of the wall. Comparison is made between the analytical and the experimental results and found to be good.

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