This equipment has been designed to demonstrate the laws of heat transfer by radiation coming from a light source and from a heat source. It consists of a framework provided with horizontal rail on which movable supports of instruments, filters and plates can slide so that they can be positioned ad different distances. A graduated scale available on the side part of rail enables to define distances exactly. The heat source consists of a flat copper element heated by means of a heating plate; the fore part of this element is coated with heatproof mat black paint ensuring an emissivity close to one. The surface temperature of the plate is measured by a thermocouple, whereas the radiation coming from the heated plate is measured by a radiometer installed along the rails.
The equipment includes:
• metallic plates with different surface finish to demonstrate the effect of emissivity on the radiation emitted and absorbed;
• three black plates, a gray plate and a polished plate that will be positioned along the rail before the heat source. Each plate is provided with a K-type thermocouple that indicates the surface temperature of the same plate;
• two cork-coated metallic plates that enable to create a vertical slot adjustable in width between the source and the measuring instrument to demonstrate the area factors.
The light source consists of a lamp that can rotate of 180°; the resulting angle is measured on a goniometer. Source power can be varied and measured. The radiation coming from the light source is measured by a luxmeter that can be positioned along the rail with graduated scale. Filtering plates of various opacity and thickness are supplied to demonstrate the laws of absorption.
TRAINING PROGRAM
This unit enables to develop and analyze the following issues:
• Reverse quadratic law using heat source and radiometer or light source and lux meter
• Stefan-Boltzmann law using heat source and radiometer
• Emissivity using heat source, metallic plates and radiometer
• Area factors using heat source, slot and radiometer
• Lambert’s cosine law using the (rotating) light source and lux meter
• Lambert’s absorption law using light source, plates with filter and lux meter
TECHNICAL CHARACTERISTICS:
• Framework with horizontal rail on which supports for instruments, filters and plates slide
• Copper Heat source, heated by means of a heating plate, black painted (emissivity close to one) and provided with
housing for thermocouple
• Radiometer
• Metallic plates with different surface finish
• Three black plates, a gray plate and a polished plate; each one provided with housing for thermocouple
• Two cork-coated metallic plates
• Lux meter
• Filters for demonstrating the laws of absorption
