CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   CFX (https://www.cfd-online.com/Forums/cfx/)
-   -   Lift Hysteresis problem in Oscillating Airfoil (https://www.cfd-online.com/Forums/cfx/25190-lift-hysteresis-problem-oscillating-airfoil.html)

Farid February 6, 2008 15:01
Lift Hysteresis problem in Oscillating Airfoil
 
I have run a simulation for Alpha(t)=10+2sinwt. I got Cd hysteresis loop as the same as experimental but I got the Opposite loop for Cl. I am getting higher lift during the downstroke but it should be lower than that of upstroke.

Can anybody help me regarding this problem.

N.B. Airfoil is NACA0012, M=0.3, Re=0.54 Million.

Glenn Horrocks February 6, 2008 16:16
Re: Lift Hysteresis problem in Oscillating Airfoil
 
Hi,

Obviously you need to validate your model. Check mesh, timestep, convergence, physics, etc etc. It all needs to be correct to get an accurate answer.

Glenn Horrocks

churchill March 28, 2012 09:34
fluent
 
Quote:
Originally Posted by Farid
;85907
I have run a simulation for Alpha(t)=10+2sinwt. I got Cd hysteresis loop as the same as experimental but I got the Opposite loop for Cl. I am getting higher lift during the downstroke but it should be lower than that of upstroke.

Can anybody help me regarding this problem.

N.B. Airfoil is NACA0012, M=0.3, Re=0.54 Million.
hello Farid, will you please tell me how to set the simulation in Fluent for hysteresis problem?I got no idea about the settings, such as the UDF,solution,boundary condition.
Thank you a lot!

ghorrocks March 29, 2012 05:52
You are posting on the wrong forum. You are looking for the Fluent forum, this is the CFX forum.


All times are GMT -4. The time now is 14:53.