Local spikes in force coefficients -- CFD Online Discussion Forums

May 1, 2019, 15:14

Local spikes in force coefficients

sjsivabharathy

New Member

jawahar sivabharathy

Join Date: Jan 2011

Posts: 12

Rep Power: 15

sjsivabharathy is on a distinguished road

Hi all,
I'm trying to solve an unsteady flow at Re = 100.
I use pisofoam solver with a time step size dt = 0.001.
My residuals are so small and maximum Courant number is 0.2.
The force coefficients on the model is periodic but sometime I get these
spikes in both Cl and Cd. I have attached them.
Could someone please explain me why this kind of behavior occurs.
I will provide any additional information if required.
Thanks,
Jawahar.

Attached Images

	cl.png (24.2 KB, 9 views)
	cd.png (15.0 KB, 6 views)

Tags

pisofoam

« Previous Thread | Next Thread »

Posting Rules
You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Trackbacks are Off Pingbacks are On Refbacks are On Forum Rules

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Aref of force coefficients in OF	giammy92	OpenFOAM Post-Processing	7	April 30, 2016 07:24
Floating point exception error	lpz_michele	OpenFOAM Running, Solving & CFD	53	October 19, 2015 03:50
[General] spatial distribution of force coefficients in paraview&openfoam	kkpal	ParaView	0	April 17, 2013 05:43
New sixDoFRigidBody BC working with laplaceFaceDecomposition	Ya_Squall2010	OpenFOAM Running, Solving & CFD	13	April 17, 2013 03:04
pisoFoam with k-epsilon turb blows up - Some questions	Heroic	OpenFOAM Running, Solving & CFD	26	December 17, 2012 04:34

All times are GMT -4. The time now is 15:50.