This paper deals with the hydrodynamic and thermal analysis of a new type of porous heat exchanger (PHE). This system operates based on energy conversion between gas enthalpy and thermal radiation. The proposed PHE has one high temperature (HT) and two heat recovery (HR1 and HR2) sections. In HT section, the enthalpy of flowing high temperature gas flow that is converted to thermal radiation em...

according to the former researcher’s presented relations for flow through rock-fill porous media, the effects of physical characteristics was not studied separately. hence, due to the application of these relations, physical characteristics of porous materials effect must be investigated separately. in various constructed physical models of porous media, the effect of several variables such as ...

1 Fellow, ASME Abstract A semi-empirical model for conduction/convection in a thin “fin-like” porous wall of arbitrary composition and thickness is developed. The model assumes one-dimensional conduction in the porous matrix and one-dimensional flow of the coolant through the wall. Closed form solutions are obtained for a uniform composition and thickness porous wall having an insulated tip. An...

a numerical model is developed to simulate the transport phenomena in the flow channel between parallel plates with porous and non-porous (or impermeable) walls. the continuity and momentum equations were solved first, assuming the wall reynolds number in the range of with the suction or injection of air at a speed equal to the uniform inlet velocity. the results show that at constant inlet and...

this work presents a numerical study to investigate the heat transfer characteristics of a 2-d rectangular composite porous radiant burner (cprb). in the construction of porous burner, the porous layer is considered to be of composite type consisting of upstream and downstream layers with equal thickness but with different physical and radiative properties. in the present work, a two dimensiona...

porous media has interesting features in compared with free flame combustion due to the extended of the lean flammability limits and lower emissions. advanced new generation of internal combustion (ic) engines are expected to have far better emissions levels both gaseous and particulate matter, at the same time having far lower fuel consumption on a wide range of operating condition. these crit...

Fluid flow through porous media is of great importance for many natural systems, such as transport of groundwater flow, pollution transport and mineral processing. In this paper, we propose and validate a novel finite volume formulation of the lattice Boltzmann method for porous flows, based on the Brinkman–Forchheimer equation. The porous media effect is incorporated as a force term in the lat...

To study the influence of localized porous silicon regions on radiofrequency performances of passive devices, inductors were integrated on localized porous silicon regions, full porous silicon sheet, bulk silicon and glass substrates. In this work, a novel strong, resistant fluoropolymer mask is introduced to localize the porous silicon on the silicon wafer. Then, the quality factors and resona...

Porous materials in general have received great attention from the last century. The development of new porous materials and the preparation of new composites based on porous materials is a subject of interest. The development of porous silicon based optical composite materials opened up new ways of incorporating optically active sol-gel materials into porous silicon. High purity silica optical...