Height Partition Effect on Combined Mixed Convection and Surface Radiation in a Vented Rectangular Cavity

The present paper reports numerical results of mixed convection and surface radiation within a horizontal ventilated cavity heated from below and provided with an adiabatic thin partition on the heated surface. Air, a radiatively transparent medium, is considered to be the cooling fluid. The effect of the governing parameters, which are the Reynolds number, 200 Re 5000, the relative height of the baffle, 0 Hb 0.75, and the emissivity of the walls, 0 1, on the fluid flow and heat transfer characteristics is studied in detail. The maximum and mean temperatures, the ratio, QE/QL, of the heat quantities leaving the cavity through the exit, QE, and through the left vertical cold side, QL, are also presented versus the above controlling parameters

TREATMENT OF TEXTILE WASTEWATER USING A CONTINUOUS FLOW ACTIVATED SLUDGE SYSTEM AT PILOT-SCALE

Textile industry wastewaters contain high concentrations of organic matter, toxic substances and dyes and pigments, and are harmful to receiving environment. Activated sludge system at pilot scale with continuous feeding, was used for the treatment of a dyeing unit effluent. The results showed that treatment allows a removal rate of 40-56 % of chemical oxygen demand (COD), and 13 to 30 % of color. The adsorption on sludge appears to be the main process responsible for the color removal of wastewater generated by textile industry

Parallel flow convection in a shallow horizontal cavity filled with non-Newtonian power-law fluids and subject to horizontal and vertical uniform heat fluxes

Natural convection heat transfer in a shallow horizontal rectangular enclosure is considered. The enclosure contains non-Newtonian fluids and is exposed to cross-gradients of temperatures. The power-law model is used to characterize the non-Newtonian fluid behavior. Analytical solution is obtained in the central region of the cavity in terms of stream function and temperature fields, assuming a parallel flow in the central part of the enclosure. The analytical results are compared against the numerical solution, obtained by solving the full governing equations using a finite difference method. It is demonstrated that multiple steady state convective flows are possible.Peer reviewed: YesNRC publication: Ye