Industrial technology and applications of Infrared radiation

THE INFRARED RADIATION AMONG THE OTHER THERMAL EXCHANGES

Infrared radiation has a special place in the heat exchanges modes.

As shown on the picture “heat transfer modes”, there are 3 modes.

• -          The first one is the conduction, the transfer of energy from a hot to a cold area of the same object.
• -          The second one is the convection, the transfer of energy by contact between a moving gas and a gas, liquid or solid.
• -          The last one, but not the least is thermal radiation, a contactless energy transfer from an emitter to an object.

The infrared radiation belongs to the family of thermal radiation.

In this family, there are several kinds of infrared radiation classified in a diagram (see picture “IR wavelengths”).

CHOOSING THE RIGHT INFRARED WAVELENGTH FOR THE BEST TREATMENT

The long wave infrared is the most classical one, somewhere between the convection and the infrared with low power density and slow reactivity.

The medium wave infrared is much more interesting for industrial lines. It can be generated with gas at high power density (up to 350kW/sqm) or electricity with lower power density (up to 70-100kW/sqm). There are several kinds of medium wave infrared emitters with each one some advantages and disadvantages. The choice of the right emitter is therefore important.

One of the most important advantages of the medium wave IR is its efficiency with water molecules for drying or water-based paint drying, and ability to enhance the Maillard reaction in food industry.

The short-wave infrared can be generated only with electricity. Its power density can reach 350kW/sqm.  Its instantaneous reactivity and ability to heat only the area in front of the radiation are its main advantages. It can be used in ATEX conditions.

The last picture shows a comparison between convection and infrared radiation.

Chaudelec Systèmes Industriels – CSI is the best partner to choose the right technology to apply.