Thermcouple Reading
 

Any one have ideas on why when fan speed is increased the thermcouple shows a lower temperature reading. Can in duct can show temperature lower than ambient. I thought no but the folks ad Omega say it's possible due to colling effect!!!. Appreciate any references to this so called cooling effect. Thanks in advance.

Re: Thermcouple Reading
 

At first sight what you are saying is not but If thermodynamic inversion takes place, then it is possible (check Joule-Thompson effect in your thermodynamics book) then check your geometry and where the thermocouple is located with respect to the velocity field, and plot the enthalpy field.