|
[Sponsors] |
July 13, 2013, 14:28 |
Strange residuals behaviour
|
#1 |
Member
xxxxx
Join Date: Feb 2013
Posts: 34
Rep Power: 13 |
Hello everybody.
I'm trying to run a very simple case: a closed volume of water (cylindrical geometry) in which a disk rotates at 303 rad/s around z-axis. I'm using OF211 and MRFSimpleFoam as solver (MRF steady state solver). The geometry is very simple and I built a structured mesh (hexa block mesh) of a quarter of the cylinder. The BCs are: - rotating disk (including shaft): no-slip walls - casing : no-slip fixed wall - cyclic AMI ( = ggi) faces The case is steady state, k-epsilon turbulence model, I order numerical schemes. For foam users, I attached the case. I first run the simulation for 3500 iterations and all seemed "normal ". Then I restared from time step 3500 to 8500 without changing any thing and the residuals shown the strange to me behaviour that you can see in the picture I attached. First they seemed to converge, than they grow again and keep higher than before. The point is that, although this strange behaviour, the fluid fields (velocity, pressure) did not show any important change between before and after and also the z-axis torque monitor shows a monotonous and converging curve (see picture). Could anyone explain me why there's this strange behaviour?
__________________
Federico |
|
July 13, 2013, 14:40 |
|
#2 |
Member
xxxxx
Join Date: Feb 2013
Posts: 34
Rep Power: 13 |
I also attach the picture of residuals.
Bye.
__________________
Federico |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
strange pressure behaviour with symmetricPlane boudary condition - interFoam | duongquaphim | OpenFOAM Running, Solving & CFD | 10 | August 20, 2013 14:00 |
Strange behaviour when using LienCubicKE and NonlinearKEShih | hani | OpenFOAM Running, Solving & CFD | 20 | March 6, 2013 10:06 |
Strange residuals of the Density Based Solver | Pat84 | FLUENT | 0 | October 22, 2012 15:59 |
kOmegaSST omega residuals strange behaviour | zordiack | OpenFOAM Running, Solving & CFD | 0 | August 8, 2012 16:23 |
Strange Residuals in CCM+ | PeterGG | Siemens | 3 | July 27, 2007 12:52 |