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-   -   Floating Point Exception - Oscilating Forces (http://www.cfd-online.com/Forums/openfoam-solving/113328-floating-point-exception-oscilating-forces.html)

A.Wendy February 18, 2013 04:20

Floating Point Exception - Oscilating Forces
 
5 Attachment(s)
Hi everybody,

i have two problems. Currently i am working on the simulation of an gyrocopter including autorotation but i got some strange problems:
when I calculate the forces/moments on my profile they are oscillating.

in the link below you find the complete cases for a static rotation and one for the autorotation added. when i run the auto rotation case my forces are increasing extremely and i have no idea why....

i am using pimpleDyMFoam and the GGI of OF 1.6 extend.

maybe some of you have ab idea.

best wishes

andy

static RPM: http://ubuntuone.com/7Eivib5v0AIGBE1pKjxk05
autorotation: http://ubuntuone.com/4Ay27nAKiikV7Uh7Gqem5c

A.Wendy February 19, 2013 05:02

hi everybody,

fault one mistake in my boundaries of the velocity and now it seemst to work better. but somehow i often get a floating point exception. when i write my data in a smaller timestep intervall and restart my computation from the latestTime the analysis is running more or less....

but this is a "dirty way" i think....

aapinillosr September 24, 2014 10:30

Work with Autogyros
 
Hi Wendy,

Currently I'm starting an investigation about CFD with Autogyros rotors with NACA 8H12 airfoil and I'm starting with OpenFoam too, if you could provide me some advice about that fact, I appreciate. Thank you


Best Regards


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