Forced Convective Heat Transfer Through Horizontal Annular Porous Channel.(Dept.M)

Abstract

In present work, the forced convective heat transfer through horizontal annular porous channel is theoretically and experimentally studied in the experimental work, annular channel with aspect ratio of 1.85 is designed such that one can study the effect of various parameters controlling the behaviour of the flow. Heat flux of 12.6 Kw/m2 to 16.9 Kw/m2 is applied to examine the effect of heat flux on heat transfer process. Porous media of diameters 3 mm and 5 mm stainless steel spherical beads are used to examine the effect of porosity on flow. Water, as a test-liquid, is used with mass flow rates of 40,50,60 and 70kg/hr. Using the obtained experimental data, the value of local and average heat transfer coefficients and Nusselt number are calculated. In the theoretical work, the govering equations describing the problem are approximated to a set of linear algebraic equations using finite divided difference technique. Computer programs are designed to solve this mathematical model. The agreement between experimental and theoretical results is fairly good in all examined conditions, especially, in case of 5 mm bead diameter medium. The results show that, higher value of heat transfer coefficient can be obtained using porous medium compared with empty channels.