Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-559-2

International Heat Transfer Conference 8
August, 17-22, 1986, San Francisco, USA

ABSORPTIVITIES OF DIFFUSE CYLINDRICAL CAVITIES

Get access (open in a dialog) DOI: 10.1615/IHTC8.4160
pages 747-750

Abstrakt

Local apparent wall absorptivities and overall absorptivities of diffuse cylindrical cavities with and without a circular diaphragm are calculated; following parametric values are considered: the surface absorptiv1ties, depth to radius and aperture to cavity radii ratios and various distributions of incoming radiation. The case of concentrated solar radiation distribution coming from a solar furnace has been studied in detail. The theoretical results are compared with those experimental obtained with various cavities without diaphragm at the focal point of a solar furnace. It has been found that for all the wall absorptivities, the cavity absorptivity increases with increasing length to radius ratio up to about 4 above which it becomes less pronounced; this dependency is more pronounced with smaller wall absorptivities.