Transport phenomena in porous media are pertinent to thermal and thermochemical processes for power and fuel generation using concentrated solar energy. The porous media serve as insulator, radiant absorbers, heat exchangers, catalyst carriers, reactants, and/or reaction sites. Volume-averaging models for porous media, commonly applied for process simulations and optimization, rely heavily on t...

UNLABELLED   The performance metrics of airflow, sound, and combustion product capture efficiency (CE) were measured for a convenience sample of 15 cooking exhaust devices, as installed in residences. Results were analyzed to quantify the impact of various device- and installation-dependent parameters on CE. Measured maximum airflows were 70% or lower than values noted on product literature for...

Recent developments in numerical schemes, turbulent combustion models and the regular increase of computing power allow Large Eddy Simulation (LES) to be applied to real industrial burners. In this paper, two types of LES in complex geometry combustors and of specific interest for aeronautical gas turbine burners are reviewed: (1) laboratory-scale combustors, without compressor or turbine, in w...

this study, combustion in a 5kW porous burner is simulated. The two dimensional Navier-Stokes, the energy and the chemical species transport equations are solved and a multistep kinetics mechanism (5 reactions and 7 species) is employed. Finite volume method is used for simulation. Thermal nonequilibrium is accounted for gas and solid temperature and radiation heat transfer is considered for so...

Within this work, a novel 50 kWth indirectly heated bubbling fluidized bed steam reformer (IHBFBSR) is presented, along with its commissioning experiments. In the IHBFBSR, heat provided through two radiant tube natural gas burners in and freeboard area. The aim of innovative design sufficient provision for biomass reforming cracking reactions loss reduction, thus allowing possibility scaling-up...

An open question in the study of quasiconvex function is the characterization of the class of functions which are sum of quasiconvex functions. In this paper we restrict attention to quasiconvex radiant functions, i.e. those whose level sets are radiant as well as convex and deal with the claim that a function can be expressed as the sum of quasiconvex radiant functions if and only if it is rad...

built of brick. At its base will be two hydrocarbon burners. Upper and lower triangular flues extend across the middle of the shaft, and also an upper and lower set of baffles or side wings, which are connected by means of wall passages or flues. Underneath these is a shelf, forming a retort in which air may mix with the flames from the burners. Flues are provided for the return of the gases ar...