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March 26, 2024, 08:58
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Ramping velocity inlet for ship simulation
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#1 |
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New Member
Antoine Haton
Join Date: Feb 2024
Location: Bordeaux, France
Posts: 4
Rep Power: 2  |
Hi Foamers,
I'm facing a problem to use a ramp as a velocity inlet for a simulation based on the tutorial DTCHull that is not using it in the v11 of Openfoam I am working on. This could improve my simulations' time of calculation as for now are working but take quite a long time. I tried to refer to these two pervious posts before asking: Trying to apply linearRamp for flow velocity in DTCHull Unsteady ramp inlet velocity that were quite recent, but I could not figure out my problem as it is a bit different. To add the ramping condition, I tried the same way a developper discribed it (here: https://github.com/OpenFOAM/OpenFOAM...b9f829e4ec3ec4) meaning I changed my inlet and outlet BC in 0/U.orig as you will see lower on this post, and added a fvModels file (I think in the 11th version of Openfoam it is called like that instead of fvOptions) in the constant/ directory. But, when I start my solver I have this error written (with the previous U.orig used I had no problems my simulation was launched directly): Code:
Pstream initialised with:
floatTransfer : false
nProcsSimpleSum : 0
commsType : nonBlocking
polling iterations : 0
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 10)
allowSystemOperations : Allowing user-supplied system call operations
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time
Create mesh for time = 0
Selecting fvMeshMover motionSolver
Selecting motion solver: rigidBodyMotion
[86] --> FOAM FATAL ERROR:
[86] cannot find file "processor86/0/pointDisplacement"
From function virtual Foam::autoPtr<Foam::ISstream> Foam::fileOperations::uncollatedFileOperation::readStream(Foam::regIOobject&, const Foam::fileName&, const Foam::word&, bool) const
[86] in file global/fileOperations/uncollatedFileOperation/uncollatedFileOperation.C at line 539.
[86]
FOAM parallel run exiting
This is the beginnng of the error message, the end is exactly the same but repeated for all numbers of processors used in parallel. I think Openfoam does not really understand the BC I want to put and this might be because of a version issue compared to the developper's reference I used, but I have nothing else to compare to or to use as a tutorial to make this work. If anyone has already faced this kind of problem or would have an idea about it I would be grateful!  Here are the files of interest: U.orig with ramping velocity inlet: Code:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 11
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class volVectorField;
location "0";
object U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
UMean 1.02889; // 2 kt
// UMean 3.08667; // 6 kt
// UMean 5.14444; // 10 kt
duration = 2.0;
dimensions [0 1 -1 0 0 0 0];
internalField uniform (#neg $UMean 0 0);
boundaryField
{
//- Set patchGroups for constraint patches
#includeEtc "caseDicts/setConstraintTypes"
inlet
{
type fixedValue;
value $internalField;
}
outlet
{
type outletPhaseMeanVelocity;
alpha alpha.water;
value $internalField;
UnMean
{
value $UMean;
type scale;
scale
{
type quarterSineRamp;
start 0;
duration $duration;
}
}
}
atmosphere
{
type pressureInletOutletVelocity;
tangentialVelocity $internalField;
value uniform (0 0 0);
}
hull
{
type movingWallVelocity;
value uniform (0 0 0);
}
rudder
{
type movingWallVelocity;
value uniform (0 0 0);
}
keel
{
type movingWallVelocity;
value uniform (0 0 0);
}
shaft
{
type movingWallVelocity;
value uniform (0 0 0);
}
}
// ************************************************************************* //
Code:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 11
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class volVectorField;
location "0";
object U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
UMean 1.02889; // 2 kt
// UMean 3.08667; // 6 kt
// UMean 5.14444; // 10 kt
dimensions [0 1 -1 0 0 0 0];
internalField uniform (#neg $UMean 0 0);
boundaryField
{
//- Set patchGroups for constraint patches
#includeEtc "caseDicts/setConstraintTypes"
inlet
{
type fixedValue;
value $internalField;
}
outlet
{
type outletPhaseMeanVelocity;
alpha alpha.water;
UnMean $UMean;
value $internalField;
}
atmosphere
{
type pressureInletOutletVelocity;
tangentialVelocity $internalField;
value uniform (0 0 0);
}
hull
{
type movingWallVelocity;
value uniform (0 0 0);
}
rudder
{
type movingWallVelocity;
value uniform (0 0 0);
}
keel
{
type movingWallVelocity;
value uniform (0 0 0);
}
shaft
{
type movingWallVelocity;
value uniform (0 0 0);
}
}
// ************************************************************************* //
pointDisplacement.orig: Code:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 11
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class pointVectorField;
location "0";
object pointDisplacement;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
dimensions [0 1 0 0 0 0 0];
internalField uniform (0 0 0);
boundaryField
{
//- Set patchGroups for constraint patches
#includeEtc "caseDicts/setConstraintTypes"
inlet
{
type fixedValue;
value uniform (0 0 0);
}
outlet
{
type fixedValue;
value uniform (0 0 0);
}
atmosphere
{
type fixedValue;
value uniform (0 0 0);
}
hull
{
type calculated;
}
rudder
{
type calculated;
}
keel
{
type calculated;
}
shaft
{
type calculated;
}
}
// ************************************************************************* //
fvModels: Code:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: dev
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "constant";
object fvOptions;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
#include "../0/U.orig";
elocityRamping
{
type velocityRamping;
active on;
selectionMode all;
U U;
velocity (#neg $UMean 0 0);
ramp
{
type quarterSineRamp;
start 0;
duration $duration;
}
}
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April 4, 2024, 04:50
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#2 |
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New Member
Antoine Haton
Join Date: Feb 2024
Location: Bordeaux, France
Posts: 4
Rep Power: 2 |
Hello there,
I have made progress with my issues. The main problem was unclear declaration of ramping inlet and outlet in 0/0.orig and fvModels in constant/. The error appeared in log.decomposePar at the end, not in log.foamRun. I should have checked all my logs thoroughly. I have attached corrected versions of U.orig and fvModels files to this message. However, I am still encountering an issue. Despite using the same expressions to describe a ramp as another thread using OF V7 (Inconsistent behaviour of function object "scale"), I'm on V11 and believe there are no differences in declaring ramping conditions. My simulation initiates, but after one iteration, I encounter the following error: Code:
Pstream initialised with:
floatTransfer : false
nProcsSimpleSum : 0
commsType : nonBlocking
polling iterations : 0
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 10)
allowSystemOperations : Allowing user-supplied system call operations
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time
Create mesh for time = 0
Selecting fvMeshMover motionSolver
Selecting motion solver: rigidBodyMotion
Selecting rigidBodySolver Newmark
Selecting solver incompressibleVoF
Selecting viscosity model constant
Selecting viscosity model constant
No MRF models present
Courant Number mean: 0 max: 0
Interface Courant Number mean: 0 max: 0
Selecting turbulence model type RAS
Selecting RAS turbulence model kOmegaSST
Selecting patchDistMethod meshWave
RAS
{
model kOmegaSST;
turbulence on;
printCoeffs on;
alphaK1 0.85;
alphaK2 1;
alphaOmega1 0.5;
alphaOmega2 0.856;
gamma1 0.555556;
gamma2 0.44;
beta1 0.075;
beta2 0.0828;
betaStar 0.09;
a1 0.31;
b1 1;
c1 10;
F3 false;
}
GAMG: Solving for pcorr, Initial residual = 0, Final residual = 0, No Iterations 0
GAMG: Solving for pcorr, Initial residual = 0, Final residual = 0, No Iterations 0
Creating fvModels from "constant/fvModels"
Selecting finite volume model type accelerationSource
Name: accelerationSource1
- selecting all cells
- selected 3521430 cell(s) with volume 15096.6
PIMPLE: No convergence criteria found
PIMPLE: No corrector convergence criteria found
Calculations will do 3 corrections
PIMPLE: Operating solver in transient mode with 3 outer correctors
forces forces_total:
Not including porosity effects
forces forces_rudder:
Not including porosity effects
forces forces_keel:
Not including porosity effects
Starting time loop
forces forces_total write:
sum of forces:
pressure : (-0.0136678 4046.13 5846.9)
viscous : (0 0 0)
porous : (0 0 0)
sum of moments:
pressure : (-694.144 -131.242 821.948)
viscous : (0 0 0)
porous : (0 0 0)
forces forces_rudder write:
sum of forces:
pressure : (0.397721 493.921 18.9689)
viscous : (0 0 0)
porous : (0 0 0)
sum of moments:
pressure : (169.498 52.1376 -1354.77)
viscous : (0 0 0)
porous : (0 0 0)
forces forces_keel write:
sum of forces:
pressure : (1.05095 13.3691 173.197)
viscous : (0 0 0)
porous : (0 0 0)
sum of moments:
pressure : (-41.7689 -23.4386 3.75107)
viscous : (0 0 0)
porous : (0 0 0)
Constructing face momentum Uf
[83] #0 [84] #0 [85] #0 [86] #0 [87] #0 [88] #0 [89] #0 Foam::error::printStack(Foam::Ostream&)[92] #0 [5] #0 [17] #0 [19] [24] #0 Foam::error::printStack(Foam::Ostream&)[25] #0 [36] #0 [37] #0 Foam::error::printStack(Foam::Ostream&)[38] #0 [44] #0 [46] #0 [49] #0 Foam::error::printStack(Foam::Ostream&)[50] #0 Foam::error::printStack(Foam::Ostream&)[52] #0 [58] #0 [60] #0 Foam::error::printStack(Foam::Ostream&)[62] #0 Foam::error::printStack(Foam::Ostream&)[63] #0 [65] #0 [66] #0 [67] #0 [68] #0 Foam::error::printStack(Foam::Ostream&)[71] #0 [72] #0 [73] #0 Foam::error::printStack(Foam::Ostream&)[74] #0 [75] #0 Foam::error::printStack(Foam::Ostream&)[78] #0 Foam::error::printStack(Foam::Ostream&)[79] #0 Foam::error::printStack(Foam::Ostream&)[80] #0 Foam::error::printStack(Foam::Ostream&)[6] #0 Foam::error::printStack(Foam::Ostream&)[7] #0 Foam::error::printStack(Foam::Ostream&)[8] #0 Foam::error::printStack(Foam::Ostream&)[9] #0 Foam::error::printStack(Foam::Ostream&)[10] #0 Foam::error::printStack(Foam::Ostream&)[11] #0 Foam::error::printStack(Foam::Ostream&)[12] #0 Foam::error::printStack(Foam::Ostream&)[14] #0 Foam::error::printStack(Foam::Ostream&)[15] #0 Foam::error::printStack(Foam::Ostream&)[16] #0 Foam::error::printStack(Foam::Ostream&)[18] #0 Foam::error::printStack(Foam::Ostream&)[20] #0 Foam::error::printStack(Foam::Ostream&)[21] #0 Foam::error::printStack(Foam::Ostream&)[22] #0 Foam::error::printStack(Foam::Ostream&)[23] #0 Foam::error::printStack(Foam::Ostream&)[26] #0 Foam::error::printStack(Foam::Ostream&)[27] #0 [28] #0 Foam::error::printStack(Foam::Ostream&)[29] #0 Foam::error::printStack(Foam::Ostream&)[30] #0 Foam::error::printStack(Foam::Ostream&)[31] #0 Foam::error::printStack(Foam::Ostream&)[32] #0 Foam::error::printStack(Foam::Ostream&)[33] #0 Foam::error::printStack(Foam::Ostream&)[34] #0 Foam::error::printStack(Foam::Ostream&)[35] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[40] #0 Foam::error::printStack(Foam::Ostream&)[41] #0 Foam::error::printStack(Foam::Ostream&)[42] #0 Foam::error::printStack(Foam::Ostream&)[43] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[45] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[47] #0 Foam::error::printStack(Foam::Ostream&)[48] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[51] #0 Foam::error::printStack(Foam::Ostream&)[53] #0 Foam::error::printStack(Foam::Ostream&)[54] #0 Foam::error::printStack(Foam::Ostream&)[55] #0 Foam::error::printStack(Foam::Ostream&)[56] #0 Foam::error::printStack(Foam::Ostream&)[57] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[59] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[61] #0 Foam::error::printStack(Foam::Ostream&)[64] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[69] #0 Foam::error::printStack(Foam::Ostream&)[70] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[76] #0 Foam::error::printStack(Foam::Ostream&)[77] #0 Foam::error::printStack(Foam::Ostream&)[81] #0 Foam::error::printStack(Foam::Ostream&)[82] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[90] #0 Foam::error::printStack(Foam::Ostream&)[91] #0 Foam::error::printStack(Foam::Ostream&)[93] #0 Foam::error::printStack(Foam::Ostream&)[0] #0 Foam::error::printStack(Foam::Ostream&)[1] #0 Foam::error::printStack(Foam::Ostream&)[2] #0 Foam::error::printStack(Foam::Ostream&)[3] #0 Foam::error::printStack(Foam::Ostream&)[4] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)[39] #0 Foam::error::printStack(Foam::Ostream&)[13] #0 Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)#0 Foam::error::printStack(Foam::Ostream&) at ??:?
[33] #1 Foam::sigFpe::sigHandler(int) at ??:?
[0] #1 Foam::sigFpe::sigHandler(int) at ??:?
[26] #1 Foam::sigFpe::sigHandler(int) at ??:?
at ??:?
at ??:?
[73] #1 Foam::sigFpe::sigHandler(int)[89] #1 Foam::sigFpe::sigHandler(int) at ??:?
[69] #1 Foam::sigFpe::sigHandler(int) at ??:?
[82] #1 Foam::sigFpe::sigHandler(int)[14] #1 Foam::sigFpe::sigHandler(int) at ??:?
[4] #1 Foam::sigFpe::sigHandler(int) at ??:?
at ??:?
[15] #1 Foam::sigFpe::sigHandler(int) at ??:?
[90] #1 Foam::sigFpe::sigHandler(int)[80] #1 Foam::sigFpe::sigHandler(int) at ??:?
at ??:?
at ??:?
at ??:?
at ??:?
[48] #1 Foam::sigFpe::sigHandler(int) at ??:?
[44] #1 Foam::sigFpe::sigHandler(int)[91] #1 Foam::sigFpe::sigHandler(int)[66] #1 Foam::sigFpe::sigHandler(int) at ??:?
[93] #1 Foam::sigFpe::sigHandler(int)[20] #1 Foam::sigFpe::sigHandler(int)[51] #1 Foam::sigFpe::sigHandler(int) at ??:?
at ??:?
at ??:?
at ??:?
at ??:?
at ??:?
[34] #1 Foam::sigFpe::sigHandler(int)[75] #1 Foam::sigFpe::sigHandler(int)[8] #1 Foam::sigFpe::sigHandler(int)[54] #1 Foam::sigFpe::sigHandler(int)[37] #1 Foam::sigFpe::sigHandler(int)[49] #1 Foam::sigFpe::sigHandler(int) at ??:?
[13] #1 Foam::sigFpe::sigHandler(int) at ??:?
[32] #1 Foam::sigFpe::sigHandler(int) at ??:?
Thank you, Antoine P.S. I apologize for the previous lengthy post, it was my first one. I'll aim to keep my messages concise in the future. U.orig_fvModels.zip |
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April 8, 2024, 10:33
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#3 |
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Senior Member
Jan
Join Date: Jul 2009
Location: Hamburg
Posts: 144
Rep Power: 20 |
Hi Antoine,
try with a very small neg. start value for your ramp, e.g. -0.00001, so you have a small velocity at time=0 s. Not sure, but I think the error you get is due to some division by zero due to zero velocity. Best, Jan |
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April 9, 2024, 10:49
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#4 |
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New Member
Antoine Haton
Join Date: Feb 2024
Location: Bordeaux, France
Posts: 4
Rep Power: 2 |
Hello Jan,
Thanks a lot for your advice, it worked! I set a very low value as internalfield for time=0 and then it started well. The simulation now converges very smoothly with the ramping inlet compared to the case without it. Regards, Antoine |
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April 9, 2024, 12:00
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#5 |
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Senior Member
Jan
Join Date: Jul 2009
Location: Hamburg
Posts: 144
Rep Power: 20 |
Good to hear that your simulation runs fine now. Yes, the ramping is quite beneficial in most cases.
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June 26, 2024, 15:21
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#6 |
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New Member
Join Date: Jun 2024
Posts: 5
Rep Power: 2 |
Hi Antoine
I was exploring the possibility of implementing velocity ramping for DTCHull too when I came across your thread. Nice to see it is doable. Would it be possible for you to post a .zip or your last working setup? This would be a great resource for many foamers! Looking forward to hearing from you. |
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July 5, 2024, 05:44
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#7 |
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New Member
Antoine Haton
Join Date: Feb 2024
Location: Bordeaux, France
Posts: 4
Rep Power: 2 |
Hi jbo,
Sorry for the late reply, I should have specified this at the end of the thread I posted, but I struggled quite a lot at the end with the ramping thing. I thought it was working but it was generating little waves as you can see on the video in the .zip I am sending this message with, and so it brought instabilities to my simulations. In the end, it was not that benefical for the study I was doing, which was on a displacement hull (low speeds). Now I am studying planning hulls and a good ramping inlet velocity would really help me as it is harder to make it converge due to the high speeds and refined mesh required. If you or anyone else knows how to get rid of these little waves generated with the ramping velocity I would be delighted. You will find in the .zip: - fvModels : to generate ramping velocity - U.orig : used with fvModels to generate ramping velocity - screencaptures of the small waves generated in the inlet (the video was too heavy) - a picture of non-convergence for the values of interest (hull behaviour and drag forces). Cheers, Antoine PS : I am using OF11. Capture1.jpg Capture2.jpg ramping.zip |
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| Tags |
| ramping inlet ship |
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