View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0003360||OpenFOAM||Bug||public||2019-10-04 10:43||2019-10-09 13:08|
|Status||closed||Resolution||no change required|
|Fixed in Version|
|Summary||0003360: Abnormal temperature of rhoReactingBuoyantFoam when the gravity sign changed.|
I have a buoyant issue about rhoReactingBuoyantFoam.
My case is premixed flame propagation in open – open tube.
My mesh is 2D axis-symmetric along x-direction.
If I change the gravity sign, g =(9.81 0 0) → g=(-9.81 0 0), abnormal temperature occurs when the flame touches the wall. It works fine for positive g, But it blows up negative g.
This is strange to me since my case is symmetric with respect to y-z plane at the center of the tube. So there is no directional preference along the x-direction. I gave the same boundary and initial condition to two ends and ignited at the center of tube.
Is there gravity sign preference for rhoReactingBuoyantFoam ?
Thank you for your help
My environment: Ubuntu 16.04, OpenFOAM-4.1
|Steps To Reproduce||1) Edit gravity sign: constant/g|
2) run rhoReactingBuoyantFoam
3) The abnormal temperature will occur at t ~ 0.014 sec if the sign is negative
|Tags||No tags attached.|
image.png (48,249 bytes)
image.png (48,249 bytes)
buoyant_issue.tar (1,402,880 bytes)
>Is there gravity sign preference for rhoReactingBuoyantFoam ?
||Yes, I think that is natural. But I can't understand this situation ...|
@hofbeer: X is defined from 0 to 200. This means that it has a gravitational reference that is different on the vector, since when g=-9.81 means that there is 0.2m of fluid weight on the domain, while on g=+9.81, it decreases with 'distance' to 0.
p_rgh = p - rho*g*height
this is what is different in your case.
Furthermore, notice how the pressure fields are initialized: https://github.com/OpenFOAM/OpenFOAM-7/blob/master/applications/solvers/combustion/reactingFoam/rhoReactingBuoyantFoam/createFields.H#L89
||Confirmed. With hRef equal to 0.2 the case runs identically with the gravity sign changed. Closing.|
|2019-10-04 10:43||hofbeer||New Issue|
|2019-10-04 10:43||hofbeer||File Added: image.png|
|2019-10-04 10:44||hofbeer||File Added: buoyant_issue.tar|
|2019-10-04 10:49||henry||Note Added: 0010795|
|2019-10-04 11:06||hofbeer||Note Added: 0010796|
|2019-10-07 10:49||wyldckat||Note Added: 0010801|
|2019-10-09 13:08||will||Assigned To||=> will|
|2019-10-09 13:08||will||Status||new => closed|
|2019-10-09 13:08||will||Resolution||open => no change required|
|2019-10-09 13:08||will||Note Added: 0010822|