Buoyancy effects in the entrance region of an inclined multi-rectangular-channel solar collector

Conference · Fri Aug 01 04:00:00 EDT 1980 · Am. Soc. Mech. Eng., (Pap.); (United States)

OSTI ID:6763417

Morcos, S M; Abou-Ellail, M M.M.

A numerical procedure is presented for the entrance region of an inclined multi-rectangular-channel solar collector with significant buoyancy effects. The upper wall heat flux is taken to be uniform, while the lower wall is assumed to be insulated. The heat flux distribution on the side wall of the rectangular channel is obtained by coupling a heat-conduction numerical procedure in the metallic region surrounding the channel to the main numerical procedure which solves the hydrodynamic and energy equations of the flow inside the channel. Numerical results are presented for water flowing in a multi-rectangular-channel solar collector with an aspect ratio AR 4 inclined at an angle alpha 30 deg to the horizontal. The resulting variable heat flux distribution on the side wall enhances the intensity of the secondary flow. The effects of the nonuniform heat flux distribution and the spacing between the rectangular channels on the variation of Nusselt number in the entrance region are presented for different values of Rayleigh number. At a value of Ra 500,000, Nusselt number is more than 300 percent above the constant property prediction.

• Research Organization: Cairo University, Cairo, Egypt
• OSTI ID: 6763417
• Report Number(s): CONF-800804-
• Conference Information: Journal Name: Am. Soc. Mech. Eng., (Pap.); (United States) Journal Volume: 80-C2/SOL-25
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors & Concentrators
CONFIGURATION
ENERGY TRANSFER
EQUIPMENT
FLUID FLOW
HEAT FLUX
HEAT TRANSFER
MATHEMATICS
NUMERICAL ANALYSIS
NUSSELT NUMBER
RECTANGULAR CONFIGURATION
SOLAR COLLECTORS
SOLAR EQUIPMENT
TEMPERATURE DEPENDENCE