Natural Convective Heat Transfer in a Divided Vertical Channel: Part II—Experimental Study

Abstract

An interferometric study has been conducted on two-dimensional laminar natural convection heat transfer in an isothermal vertical divided channel. Interferograms were obtained for air and a plate-to-channel length ratio of Lp/Lc= 1/3. Data are presented for the dividing plate located at the bottom (Li/Lc = 0) and top of the channel (Li/Lc=2/3). Comparisons of local and average Nusselt numbers are made with the numerical predictions from Part I. Although the experimental average Nusselt numbers are typically about 10 percent lower than the numerical results, the general trends of the data are in good agreement. Average Nusselt number correlation equations are presented.

Combined radiative and convective heat transfer in a divided channel

“…In the case of a divided channel, comparisons of local and average wall Nusselt numbers, mass flow rates, and average channel Nusselt number were made with those given numerically and experimentally by Naylor and Tarasuk (1993a, b). In all cases, the present calculations gave identical results.…”

“…Next, natural convection heat transfer in a divided vertical channel was considered. The solutions obtained for a divided vertical channel are compared with those of Naylor and Tarasuk (1993a, b).…”

“…In all cases, the present calculations gave identical results. For example of this validation, we present in Table III, the average wall Nusselt number, Nu w and the plate Nusselt number, Nu p obtained by our code and those of Naylor and Tarasuk (1993b) shown in Table I (p. 391).…”

Radiation effects on natural convection in a vertical channel with an auxiliary plate

“…The highest average Nusselt number for complete system (channel and plate as a whole) was obtained by positioning the plate at the bottom of the channel. The experimental study [29] was obtained by means of a Mach-Zehender interferometer and the auxiliary plate was located at the bottom and top of the channel and its dimensionless height was 1/3. Experimental and numerical results were in good agreement even if the experimentally measured average Nusselt numbers were about 10% lower than the numerical results.…”

“…[28] and experimentally in Ref. [29]. The numerical study [28] showed that the heat transfer rate from the auxiliary plate can be significantly enhanced by the presence of the channel walls.…”