Enhancement In Forced Convection Heat Transfer From A Heated Triangular Cylinder By Using Porous Media

Across flow forced convection heat transfer around a triangular cylinder (0.015 m hydraulic diameter) embedded in porous media of spherical particles made of (Polypropylene, glass and alumina) with (4.73, 5, 4.5 mm) diameter, respectively has been experimentally investigated. Air was used as working fluid at a Reynolds number (1089- 1422). The effects of particles materials with different thermal conductivities (0.248 W/m .k for polypropylene, 0.78 W/m .k for glass and 30 W/m .k for alumina) were studied. The triangular cylinder was heated at constant heat flux (4910 W/m2). The results manifested that the coefficients of higher heat transfer were determined when using a high particle thermal conductivity and the heat transfer coefficients with (Polypropylene, glass and alumina) were (2.28, 3.85 and 4.9) times that for the empty duct. The correlations of Nusselt number with Peclet number for various material particles were provided. Finally, a comparison was made between the experimental results and the preceding studies and gave a reasonable agreement.