|March 20, 2012, 23:09||
Discretization Error vs Residual Error?
Join Date: Jul 2009
Location: Montreal, Canada
Posts: 154Rep Power: 9
I just ran a sensitivity study on my case to see if I could improve my accuracy by using SFCD (2nd order scheme for convection terms) vs linearUpwind (1st order accurate). All else being equal, the SFCD case had a p-residual of 5e-1 and the linearUpwind case had a p-residual of 10e-3. I expected better accuracy from the 2nd order accurate case, but the residuals appear to show that was not the case. I am running simpleFoam on a 2D airfoil. Could anyone please suggest why the residual is higher for the 2nd order scheme?
More strange behaviour: the SFCD took LESS time to execute the case, and resulted in values of Cd and Cm that were farther from the experimental data than the upwind scheme. I expected different. Can anyone explain this?
|March 21, 2012, 03:49||
Join Date: May 2009
Location: Delft, Netherlands
Posts: 1,139Rep Power: 20
I always thought linearUpwind is 2nd order upwind. Is plain "upwind" what you were intending to compare to?
*On twitter @akidTwit
*Spend as much time formulating your questions as you expect people to spend on their answer.
*Join the OpenFOAM stackexchange Q&A site: http://area51.stackexchange.com/prop...oHPxcPqde7HtA2
|Thread||Thread Starter||Forum||Replies||Last Post|
|problem with Min/max rho||tH3f0rC3||OpenFOAM||7||February 23, 2013 06:37|
|Full pipe 3D using icoFoam||cyberbrain||OpenFOAM||4||March 16, 2011 10:20|
|lift and drag on ship superstructures||vaina74||OpenFOAM Running, Solving & CFD||3||June 8, 2010 12:30|
|Unknown error||sivakumar||OpenFOAM Pre-Processing||9||September 9, 2008 12:53|
|Could anybody help me see this error and give help||liugx212||OpenFOAM Running, Solving & CFD||3||January 4, 2006 19:07|