Heat fluxmeters principle

This textile heat fluxmeter consists of a network of thermocouples (assembly of two dissimilar conductor or semiconductor), also called a thermopile, assembled into a textile auxiliary wall. Thus, heat and mass transfer properties of textile substrate used as auxiliary wall will be smdied in the first part of this work. Afterward, the principle and the production technology of the conventional heat fluxmeters and the textile heat fluxmeter will be defined. 

Since a textile substrate is used as an auxiliary wall to create the textile heat flux-meter, die performance of this heat fluxmeter is influenced by textile substrate properties. The first part of this chapter is especially concerned with the complex phenomena of the heat and mass transfers. The following section presents the principles and the production processes of the conventional and textile heat fluxmeters. 

The principle of the gradient heat fluxmeter is to observe a heat flux due to the evaluation of the temperature gradient between the two faces of the conducting support, which has known thermal characteristics. This temperature gradient is measured by a thermocouple (assembly of two dissimilar conductors or semiconductors) or rather a number of thermocouples forming a thermopile. 

Only a few companies commercialize gradient heat fluxmeters and all of them use the same principle described above the transfer of the heat flux generates a temperature gradient on the thermopile, which delivers an output voltage proportional to the heat flux. 

---