How to make the convergence of fluid machinery better

max610105 · August 31, 2017, 09:30

hi all
I use fluent to to simulate a centrifugal fan.
My settings are as follows

Solver type:Pressure based
Velocity Formulation:Absolute
Time:steady
Model:K-e (RNG)<i try k-omega too
solution methods:simple
when fan speed is 1000 RPM , Volume flow rate is more steady than 10000 RPM
I try different turbulence model and more dense mesh
it didn't work

could someone can tell me how to solve this kind of problem thanks a lot

CeesH · August 31, 2017, 09:37

How are you modeling the fan itself? Did you try a transient rather than steady state simulation? If there are inherent periodic effects, forcing into steady state may give issues. (and why RNG k-e? in my experience, it performs really poor for stirred vessels, so I expect little better for fans)

max610105 · August 31, 2017, 22:35

sorry i don't know what you mean in first question(I use pro/e to model the fan)
because transient need more time , thanks for the information i will try transient state simulation again
in you experience , which model is better?

August 31, 2017, 09:30	How to make the convergence of fluid machinery better	#1
max610105 New Member max wang Join Date: Sep 2014 Posts: 2 Rep Power: 0	hi all I use fluent to to simulate a centrifugal fan. My settings are as follows Solver type:Pressure based Velocity Formulation:Absolute Time:steady Model:K-e (RNG)<i try k-omega too solution methods:simple when fan speed is 1000 RPM , Volume flow rate is more steady than 10000 RPM I try different turbulence model and more dense mesh it didn't work could someone can tell me how to solve this kind of problem thanks a lot

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August 31, 2017, 09:37		#2
CeesH Senior Member Cees Haringa Join Date: May 2013 Location: Delft Posts: 607 Rep Power: 0	How are you modeling the fan itself? Did you try a transient rather than steady state simulation? If there are inherent periodic effects, forcing into steady state may give issues. (and why RNG k-e? in my experience, it performs really poor for stirred vessels, so I expect little better for fans)

August 31, 2017, 22:35		#3
max610105 New Member max wang Join Date: Sep 2014 Posts: 2 Rep Power: 0	sorry i don't know what you mean in first question(I use pro/e to model the fan) because transient need more time , thanks for the information i will try transient state simulation again in you experience , which model is better?