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An analytical investigation of the performance of a heat exchanger containing a conductive porous media was made. The partial differential equations governing the steady-state temperature distributions for both the porous media and the coolant fluid are given. A method for obtaining an approximate solution of the governing equations is shown. A computer program was written in FORTRAN IV and the results are provided for determining the cooling effectiveness.

Measurements were performed to determine the pressure drops for gaseous flow through porous materials of different microstructures, porosities, and thickness under isothermal and nonisothermal conditions at various temperature levels. Results were satisfactorily correlated by a simple equation relating the friction factor to the Reynolds number and porosities.

The aerodynamic and heat-transfer characteristics for flow over an upstream-facing cylindrical cup simulating a parachute geometry were studied. It was found that: (1) The pressure on the bottom of the cup increases as the depth of the cup increases. (2) An increase in the free-stream turbulence level increases the aerodynamic heat transfer significantly. (3) The heat transfer front the bottom of the cup decreases monotonically as the depth of the cup increases. (4) The effect of suction at the cup bottom is to equalize the pressure distribution and to increase the heat transfer.

Laminar free convection from a nonisothermal horizontal cylinder is analyzed. The wall surface temperature is assumed to be varied in the manner of a1(x/R)2 + a2(x/R)4. Special transformations are devised and employed so that the resulting differential equations and boundary conditions are free of the parameters a1 and a2. These differential equations are solved once and for all; solutions to the original equations for any particular values of a1 and a2 may then be read off easily as linear combinations of the numerical solutions given here. It is found that the dependence of heat transfer from a horizontal cylinder on Prandtl number is practically the same as that from a vertical plate. Furthermore, the heat transfer is greatly influenced by the surface temperature variations.

The nonsimilar boundary-layer flow and heat transfer of a cone rotating in a forced-flow field are investigated. Numerical solutions are shown for a half-cone angle of 53.5 deg with parameters (vw/ue)2 ranging from 0 to 20, and with Prandtl numbers from 0.2 to 10. With a half-cone angle of 90 deg (so that one has a rotating disk), the degenerate problem is solved in the same manner.

The friction coefficient for both laminar and turbulent flow through rectangular channels was analytically and experimentally studied. The analytic expression for the pressure loss in fully established laminar flow was verified by experiment. In turbulent flow, the method of Deissler and Taylor was used to calculate the friction coefficient. The calculated and measured results were in agreement for ducts having large aspect ratios. At aspect ratios less than 5:1, the predicted values of the friction factors were lower than the experimental data, with a maximum difference of 12 per cent evident for the square duct. It was found that the circular-tube correlation accurately predicts the friction coefficient for flow through rectangular ducts of any aspect ratio for Reynolds numbers between 6 × 103 and 5 × 105. Hydrodynamic entrance-length results are also presented in the laminar and turbulent flow ranges for both a smooth and an abrupt entrance configuration.

The two phase flow problem in laminar film boiling on a vertical flat plate is analyzed. The shear stress and vapor velocity at the vapor-liquid interface are taken into account. The problem is treated by solving simultaneously the boundary-layer equations for the vapor and liquid phases. In contrast to the film-condensation problem where the heat transfer is independent of the ρμ ratio, and where the interfacial shear can be neglected for a Prandtl number of unity or larger, it is shown that the ρμ ratio is an important parameter in the film-boiling heat transfer, and that the interfacial shear is quite different from zero.

By using the integral method, the task of solving the complicated two-phase boundary-layer differential equations in laminar-film condensation has been reduced to the simple work of solving an algebraic equation. It was shown analytically that the parameter [(ρμ)L/(ρμ)v]1/2 can be removed from the film-condensation problem and hence only two parameters, cpΔT/hfg and Pr, are involved. The calculated results in heat transfer and condensate flow rates agree very well with the results from the exact solution of the boundary-layer equations. With [(ρμ)v/(ρμ)L]1/2 remaining as a parameter, it is believed that the present method can be used to solve the analogous two-phase boundary-layer problem in laminar film boiling.