Natural Convection in an Inclined Rectangular Channel Heated From the Bottom Surface

The phenomenon of natural convection in an inclined rectangular channel heated from the bottom surface has been experimentally investigated. The experiments covered a range of modified Rayleigh numbers Ra_d^*, by using the shortest distance d between two opposing side walls as a representative length, between 1.8 × 10² and 6 × 10⁵, and a range of inclination angles of the side wall with respect to the horizontal θ between 30 deg and 90 deg. Air was used as the working fluid. An experimental correlation equation is given for the Nusselt number Nu_d as a function of sin θ and Ra_d^* for W/l (width to length of the channel) = 0.1–0.5.