Diagram of radiation pyrometer.
Diagram of radiation pyrometer.

Explain radiation pyrometer:

What is radiation pyrometer? A device which measures the total intensity of radiation emitted from a body is called radiation pyrometer.

The elements of a total radiation pyrometer are illustrated in figure. It collects the radiation from an object (hot body) whose temperature is required. A mirror is used to focus this radiation on a thermocouple.

This energy which is concentrated on the thermocouple raises its temperature, and in turn generates an e.m.f. This e.m.f. is then measured either by the galvanometer or potentiometer method. Thus rise of temperature is a function of the amount of radiation emitted from the object.

Advantages of the pyrometers:

  • The temperatures of moving objects can be measured.
  • A higher temperature measurement is possible than that possible by thermocouples etc.
  • The average temperatures of the extended surface can be measured.
  • The temperature of the objects which are not easily accessible can be measured.

What is total radiation pyrometer?

The total radiation pyrometer receives all the radiation from a particular are of hot body. The term total radiation includes both the visible and invisible radiations. It consists of radiation receiving element and a measuring device.

What does a pyranometer measure?

A pyranometer is a type of actinometer used for measuring solar irradiance on a planar surface and it is designed to measure the solar radiation flux density (W/m2) from the hemisphere above within a wavelength range 0.3 μm to 3 μm.

What is the difference between thermometer and pyrometer?

The difference between thermometer and pyrometeris that thermometer is an apparatus used to measure temperature while pyrometer is a thermometer designed to measure high temperatures.