Analysis of a Porous-Medium Solar Collector

Abstract

The porous-medium flat-plate solar collector is an interesting alternative to conventional fin land-tube designs if higher pumping power requirements do not offset collector efficiency gains. In this paper, complementary to a transient two-phase heat transfer study where Darcy's law had been used, a non-Darcy flow equation and the convection-conduction heat transfer equation are solved numerically. The coupled fluid flow and heat transfer mechanisms are analyzed for a porous-medium solar collector, and its high-performance efficiency is compared with advanced tubular-type collectors.

Computational modeling of heat transfer in an annular porous medium solar energy absorber with the P1-radiative differential approximation

“…For higher velocity flows however, beyond a Reynolds number of 10, and in porous media of large pore radius, the Darcy model is no longer sufficient to accurately simulate porous media hydrodynamic effects since it neglects inertial drag forces and also boundary vorticity diffusion (Brinkman friction) effects which become significant at higher velocities and near enclosing boundaries, respectively. Kleinstreuer and Chiang [22] [29] investigated the mixed radiation-convection flow of an optically dense viscous fluid in a non-Darcy porous medium using a diffusion approximation. Transient radiation-convection flow in porous media have also been studied for the Darcian case and non-Darcian case, respectively by Bég et al [30,31] using Network Simulation Methodology (NSM).…”

Energy and exergy analysis of an enhanced solar CCHP system with a collector embedded by porous media and nano fluid

“…Kleinstreuer and Chiang [16] have solved the thermal and fluid transfer equations in a flat plate collector covered by porous material and compared its thermal efficiency with a conventional collector. Their research results showed that the solar collector with porous media has higher absorption and thermal stability.…”