- #1
dRic2
How can I choose the characteristic linear dimension? For example in pipe it is its diameter, but on a surface is the length, on a flat plane it can be measured as 4A/P. I was having problems determining the characteristic linear dimension for a diffusion problem in a "rectangular" pipe. I don't know if I have to use the length L or 4A/P.
Here's the picture of the problem
Here's the picture of the problem