[iigo]

Hello CFD users,

I´m having trouble trying to simulate the following problem. In a 20 mm diameter pipe and 100 mm of length flows water, with a mass flow rate of 0.3 kg/s. The results without ANSYS would be of a v=0,95684, Re=21434, lambda = 0,025, pressure drop (Darcy-Weisbach) = 58,1317 Pa.
I have introduced the problem to Fluent with the k-epsilon Enhanced Wall Treatment option (I´m very interested in the solution of the laminar layer in the turbulent flow), and I wanted to make the conditions translationally periodic.
I have made the velocity inlet the periodic zone and the pressure outlet the shadow zone, and I have inserted in the periodic conditions a mass flow rate of 0.3 kg/s and pressure gradient of 581,317 Pa.
When I simulate it, however, the error in continuity rapidly rises. I am doing something wrong in Fluent, but I don´t know why ¿what can it be? (I have just started learning this program one month ago).

Kind regards

[LuckyTran]

You only have 50 iterations. Keep cranking. The turbulent viscosity warning also needs to go away. At this point, the quality of your initial guess is still strongly impacting the current solution.

Btw, if you use the mass-flow rate option, you can't specify also the pressure gradient. Putting in a number there doesn't do anything. The gradient is a result calculated from the solution.

[iigo]

Thanks for replying! I have tried to iterate more (until 1200), and I have obtained the results in the picture that I attach. The continuity one is not converging. By the way, LuckyTran, when you say that the turbulent alert needs to go away, does it mean that there is a manual way to deactivate it?