Non-constant heat flux (as a function of wall temperature))
 

Transient heat transfer modeling.
There are 3 thermoelectric coolers on the bottom of a chamber. The heat flux is a function of the temperature of the cooler (wall temperature), q=f(T), the larger the temperature is, the smaller the heat flux will be.
In other words, it's about how to create a wall heat flux function with respect to its temperature.
Can this problem be solved using expressions or functions inside CFX?:)

Use a CEL expression on the heat flux boundary. "Wall heat flux = 100 [W m^-2 K^-1] * T" should work as an example.