thermal model

Hi everyone,


I am working on a thermal model and used conjugate heat transfer for simulation. My problem is when i want to calculate the thermal efficiency of the flowing fluid (cooling) by identifying (T out) at the end of the channel, the efficiency value is unrealestic! in a sense that this thermal efficiency is more than 95%.

The equation i am using to calculate the thermal efficiency is: Thermal efficiency= Energy of water/Energy in= rho*U*A*Cp*(Tout-Tin)/q_rad*surface area. (Tin is 298.15 K)

Is there any other way to calculate the Thermal efficency of the cooling water using comsol instead of extracting the value of the Tout and plug it to the above equation? or what is the most reliable value of Tout that would give me a more reasonable thermal efficiency.

Thank you in advanced.

Abdul