图书馆订购 Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-909-1

International Heat Transfer Conference 9
August, 19-24, 1990 , Jerusalem, Israel

COMBINED CONVECTIVE FLOW IN AN INCLINED PLANE DUCT WITH UPPER AND LOWER SURFACES HEATED TO DIFFERENT TEMPERATURES

Get access (open in a dialog) DOI: 10.1615/IHTC9.2480
pages 459-464

摘要

Indirect natural convective solar crop dryers normally utilize a simple solar air heater consisting of an inclined wide lower plate that is heated by the sun and an upper parallel transparent cover through which the solar energy passes. The air that dries the crop is then drawn by the buoyancy forces through the passage between the heated lower plate and the upper cover. In order to study the heat transfer characteristics of such collectors, two-dimensional steady laminar mixed convective flow between parallel plates inclined at an angle to the horizontal has been considered. The lower plate is assumed to be at a uniform temperature. In previous studies of this type of flow it has usually been assumed that the upper plate is adiabatic. In a real situation, however, the transparent upper surface will absorb some of the incident solar radiation and will also be exchanging heat with the ambient air. In the present study it has, therefore, been assumed that the upper surface is also at a uniform temperature but that this is different than the temperature of the lower plate. The parabolic flow equations have been assumed to apply and these equations, written in dimensionless form, have been numerically solved using a forward - marching finite -difference procedure.