thermal exchange with flow in transition zone

[MrGil]

Bye to all,
for a couple of months I am simulating a transient in fluent related to oil flow in a steel piping. hot oil heats through the tube a sleeve of material that wraps the tube itself and which acts as a sensitive heat accumulation. I have to try to reproduce numerically a laboratory experience with its results. Of course, turbulence is of fundamental importance, since it depends on the heat exchange coefficient of oil. the number of reynolds is around 1900, from literature we should be purely laminating, yet the most accurate results and close to reality I obtained them through the model of turbulence "transition sst". Does anyone have more experience in this matter and can make me think about my choice? Do you have better ideas?
Thank you.

 

[lucar4980]

It's a very complex problem. you are working in a transition zone and the results are to be taken with the springs. actually the model of turbulence you have chosen is among the most reliable in the case of low reynolds heat exchange.
you could try a gamma-re-theta transition model. the results however should be somewhat calibrated with some experimental reference.

 

[lucar4980]

I've been thinking a little more about your problem, actually the reynolds is low, except unforeseen, you should have laminar flow. . How big is the error you get from the laminar simulation? have you checked whether the solution is affected by the calculation grid or by the numerical scheme?