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Experimental measurements and data correlations for the divided channel obtained in part I of the experimental study are analyzed in the second part. Interferometric study was conducted on two-dimensional laminar natural convection heat transfer in an isothermal vertical divided channel. Interferograms were arrived at for air, and a plate-to-channel length ratio of Lp/Lc=1/3. Comparative studies of local and average Nusselt numbers with the numerical predictions from part I show that although the average Nusselt numbers are 10 percent lower than the numerical results, the general trends of the data are in accordance with each other.

A two-part study of two-dimensional laminar natural convection heat transfer in a divided vertical channel examines the effect of Rayleigh number, plate-to-channel length ratio, vertical plate position, and plate thickness on the heat transfer rate form the channel walls, the dividing plate and the channel as a whole. Part I answers the full elliptic and parabolic forms of the Navier-Stokes. Energy equations for Prandtl number Pr=0.7 are also obtained.

The influence of the angle of inclination on the spontaneous convection heat transfer from an isothermal channel is studied. An increase in the angle of inclination leads to a decrease in the overall heat transfer, which is proportional to the angle of inclination. There is no significant asymmetric heat transfer along each wall in the range of parameters studied.

The influence of heated, horizontal and rotateable louvers on the convective heat transfer from a heated or cooled vertical isothermal surface is examined. The effect of the heated louvers on the heat transfer rate from the plate surface is demonstrated and the results of the numerical study are validated.

The influence of heated, horizontal and rotatable louvers on the convective and radiative heat transfer from a heated or cooled vertical isothermal surface is investigated. The result is obtained using a steady, laminar two dimensional conjugate conduction finite element model for two window temperatures such warm and cool compared to ambient as well as irradiation levels.

Experiment conducted for determining accuracy of beam-averaged interferometric heat transfer measurements in ideal gases is reported. The results demonstrate that the associated intrinsic error is not the same in all cases.

Laser interferometry and flow visualization were used to study free convective heat transfer inside a vertical channel. Most studies in the literature have investigated buoyancy forces in a single direction. The study presented here investigated opposing buoyancy forces, where one wall is warmer than the ambient and the other wall is cooler than the ambient. An experimental model of an isothermally, asymmetrically heated vertical channel was constructed. Intetferometry provided temperature field visualization and flow visualization was used to obtain the streamlines. Experiments were carried out over a range of aspect ratios berween 8.8 and 26.4, using temperature ratios of 0, --0.5, and --0.75. These conditions provide a modified Rayleigh number range of approximately 5 to 1100. In addition, the measured local and average Nusselt number data were compared to numerical solutions obtained using ANSYS FLUENT. Air was the fluid of interest. So the Prandtl number was fixed at 0.71. Numerical solutions were obtained for modified Rayleigh numbers ranging from the laminar fully developed flow regime to the turbulent isolated boundary layer regime. A semi-empirical correlation of the average Nusselt number was developed based on the experimental data. [ABSTRACT FROM AUTHOR]

Laser interferometry is combined with high-speed digital cinematography to measure time-averaged transient and turbulent convective heat transfer rates. The method is applied to study free convection in a tall vertical air-filled enclosure. Measurements are made at three wall spacings in the turbulent flow regime (5.2×104 ⩽ Raw ⩽ 2.8×105). An automated image processing algorithm is used to calculate the instantaneous local heat flux from a sequence of interferograms that is captured by a high-speed camera. The local Nusselt number distributions on the hot and cold walls are obtained by time-averaging the fluctuations in local heat flux. The effects of key experimental parameters, such as the camera frame rate and the total image capture time, are investigated. For the current problem, it is shown that a total capture interval of about 10 s is required to accurately measure the time-average local Nusselt number. Within the measurement uncertainty, the average Nusselt number results are in agreement with a widely used empirical correlation from the literature. [ABSTRACT FROM AUTHOR]