Solar radiation induced natural convection in enclosures with conducting walls

✍ Scribed by M. Hasnaoui; Z. Zrikem; P. Vasseur; E. Bilgen

• Publisher: Elsevier Science
• Year: 1990
• Weight: 602 KB
• Volume: 7
• Category: Article
• ISSN: 0741-983X
• DOI: 10.1016/0741-983x(90)90056-8

✦ Synopsis

Abstraet--A theoretical study is presented on combined heat transfer by conduction, convection and radiation in a rectangular cavity with an aspect ratio of 1 to 0.2. Constant flux solar radiation at a given incidence angle is transmitted through one of the vertical boundaries and they are absorbed by the enclosure walls. The temperature distribution within the cavity is computed in an iterative manner by the net radiation method, using solution results from the heat transfer by conduction and natural convection. It is found that the radiation and conduction have a significant effect on the flow field and heat transfer. The induced radiation has a stabilizing effect on the flow field with a tendency to make the secondary cells disappear. This effect increases with increasing solar radiation intensity and incidence angle and with decreasing aspect ratio. As a result, the net energy absorbed and transferred through the end wall is also increased. A correlation for combined heat transfer is also derived which can be used in passive solar wall collector design.