Maximizing Heat Transfer in Ansys: Tips for Defining Wall's Heat Capacity"

[mark_dynamite]

Hi, I am trying to show the heat transfer from a hot stream to a cold stream in ansys. I can do everything but not to define the wall's heat capacity which separates the two streams. Where and how would I do this? Thanks

 

[mrmiller1]

It sounds like you're looking for the overall heat transfer coefficient, U. This value is always given from the vendor in the TEMA sheet for the heat exchanger (HX). The TEMA sheet has all of the data you would ever need to do any type of analysis.

A heuristic value for U is 0.8517 kJ/m²-K-s (= 150 btu/ft²-F-hr)
So the heat transferred is given by...
Q=mC_pΔT=UAΔT_LM
Q [kJ/s]
m [kg/s]
Cp [kJ/kg-K]
ΔT [K]
U [kJ/m²-s-K]
A [m²]
ΔT_LM [K]

Most likely you're aware, but the mCpΔT is of either the tube side or shell side fluid. The A is the heat transfer area. For example, if you have n number of tubes in the HX and each has a diameter of D with a length of L, then...
A= (pi)DLn (for a 1-pass HX)