Natural Convective Heat Transfer in a Divided Vertical Channel: Part I—Numerical Study

Abstract

This is a two-part study of two-dimensional laminar natural convection heat transfer in a divided vertical channel. The divided channel consists of an isothermal dividing plate located on the center line of a vertical channel formed by two isothermal walls. The study examines the effect of Rayleigh number, plate-to-channel length ratio, vertical plate position, and plate thickness on the heat transfer rate from the channel walls, the dividing plate, and the channel as a whole. In Part I, solutions to both the full elliptic and parabolic forms of the Navier–Stokes and energy equations are obtained for Prandtl number Pr = 0.7 (air). Positioning the plate at the bottom of the channel was found to give the highest average Nusselt numbers for the plate and channel. Dividing plate average Nusselt numbers as much as two times higher than the isolated plate Nusselt number were predicted numerically. Experimental measurements and data correlations for the divided channel are presented in Part II of this paper.

Maximal heat transfer density: Plates with multiple lengths in forced convection

“…, and thickness t are inserted between the long plates. A related geometry has been studied numerically in [9]. The flow through the plates is laminar forced convection driven by the imposed pressure difference P .…”

Optimum natural convection from square cylinder in vertical channel

“…These two limits were referred as the fully developed limit and single plate limit. Moreover, in Naylor and Tarasuk (1993a), these two limits have been established for the vertical plate inside a channel and referred as the fully developed limit and isolated plate limit. In the present configurations the two limits may also be referred to the fully developed limit and unconfined cylinder limit.…”

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

“…[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. 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.…”

“…An analysis of the configuration with the channel walls and the auxiliary plate at uniform temperature was carried out numerically in Ref. [28] and experimentally in Ref. [29].…”