Emissivity Measurement Apparatus:
The apparatus consists of a test plate and a comparator. A black plate
is used as a comparator for test plate. When all the physical, dimensions and the temperatures are equal, heat losses from both plates will also be the same, except radiation losses. Hence the input difference will be due to difference in emissive. Both the plates are kept in a panel enclose with perplex front and are given inputs through separate dimmer stats so that temperatures of both can be kept equal. Thus emissivity can determine over a wide range of temperatures.
Test plate and Black plates — 160mm. Dia. Aluminum plates, mounted in Panel with mica heater inside.
Instrumental panel consisting of-
A technical manual accompanies the unit.