HEAT TRANSFER IN NATURAL CONVECTION

The setup consists of a brass tube fitted in a rectangular duct in a vertical position. The duct is open at the top and bottom and forms an enclosure that serves the purpose of the undisturbed surrounding. One side of the duct is fitted with a transparent acrylic window for visualization. An electric heating element is kept in the vertical tube that in turn heats the tube surface. The heat is lost from the tube to the surrounding air by natural convection. The temperature of the vertical tube is measure by temperature sensors and displayed by a Digital Temperature Indicator with a multi-channel switch. The heat input to the heater is measured by a Digital Ammeter and a Digital Voltmeter and is varied by a variac. The tube surface is polished to minimize radiation losses.