The setup consists of a brass tube fitted in a rectangular duct in a vertical fashion. The duct is open at the top and bottom, and forms an enclosure and serves the purpose of undisturbed surrounding. One side of the duct is fitted with a transparent good quality Acrylic window for visualization. An electric heating element is kept in the vertical tube that in turns 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 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 the radiation losses.

The setup consists of a brass tube fitted in a rectangular duct in a vertical fashion. The duct is open at the top and bottom, and forms an enclosure and serves the purpose of undisturbed surrounding. One side of the duct is fitted with a transparent good quality Acrylic window for visualization. An electric heating element is kept in the vertical tube that in turns 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 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 the radiation losses.