MATLAB: Heat exchanger (G-G) parameter

fluidsheat exchangerSimscapeSimscape Fluids

Hello,
I have a question regarding a parameter in the heat exchanger block in simscape. When I select the Nusselt-Reynolds-Prandlt correlations for the heat transfer parametrization I have to define the "Length of flow path for heat transfer". What is this parameter exactly defining?
At first, I thought it was the total length of the pipe of the heat exchanger for each side, as the default parameter was 1 meter. But reading the description I got confused as it says: "Characteristic length traversed in heat transfer between fluid and wall. This length factors in the calculation of the hydraulic diameter from which the heat transfer coefficient and the Reynolds number, as defined in the tabulated heat transfer parameterizations, derives.", reading this description makes me think it is the distance from the center of the pipe to the exterior face of the same.
If anyone could clarify this It would be great
Thank you in advance,

Best Answer

Hi Carlos,
Your first impression is correct.
The Length of flow path for heat transfer corresponds to the length of the piping or channel between the exchanger inlet and outlet. I've let our documentation team know about the error in the parameter definition section.
Please let me know if you have any further questions.
Best,
Sarah