I have just submitted my dissertation but my committee feels as though the boundary conditions of my models and of a few analytical solutions are not "defined clearly enough" in the paper. I feel as though I DID describe them, so I'm not 100% what they want. What you would do: Look at TWO models in COMSOL and extensively define their boundary conditions for me. (You don't have to have COMSOL installed - I can send you screenshots of how I've set it up). Look at one analytical solutions for heat transfer and define the boundary conditions and assumptions associated with them. You will write this up for me in Word - I am hoping a comparison between what I wrote and what you write will expose what I am missing in my report.