Natural convection from a horizontal plate built in a vertical variable height duct
Hadeel Abdulhadi Jasim, Fadhel abbas abdalla, Adnan A. Abdulrasool
Abstract
Abstract Natural convection from flat plate built in variable height duct was investigated experimentally. With air as the working liquid the impact of variable height duct on the heat transmission of the flat panel were studied. Duct was with Square section of (300×300) mm 2 and the elevation of the duct H was various asl00, 200 and 300 mm. square flat plate (300×300) mm 2 which heated surface facing upwards, was built in the bottom of the duct and exposed to different input power which represent a heat flux of (423, 660 and 830 W/m 2 . The experimental results showed that the variable height duct deteriorate the heat transmission. heat transmission of the flat panel built in a variable height duct become lower than those do not have a channel and heat transmission are significantly reduced in the circumference of the duct. at circumference of variable height duct, heat transmission for flat board become 27% smaller than heat transfer for flat panel that do not have a duct owing to that the perpendicular duct hinders airflow from the top of the perpendicular duct this causes decrease of heat transmission.