CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

reactingMultiphaseEulerFoam

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree1Likes
  • 1 Post By tonnykz

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 12, 2019, 11:27
Default reactingMultiphaseEulerFoam
  #1
New Member
 
Join Date: Oct 2016
Posts: 29
Rep Power: 6
tonnykz is on a distinguished road
Hello to everyone,
As I've mentioned in my previous thread (chtMultiRegionFoam with multiple liquid regions) I am using OF6 for my research project, aims of which to model gas-water interaction involving heat transfer, chemical kinetics, mass transport. I was trying to use chtMultiRegionFoam and got stuck with multiple problems:
1. Gas doesn't drag water. Tried various BC between regions.
2. Chemical species can't diffuse into neighbor region.
3. Can't have inter-region chemical reactions.
4. Pressure and velocity diverging. What bothers me most.

So, currently (with the advice of Robin.Kamenicky) I have switched to reactingTwoPhaseEulerFoam. Which should be able to solve my case correctly.

Simulation domain consists of two fluids: gas, flowing from left to right with defined velocity, on top of the water, that is still initially and dragged by gas. Dimensions of whole domain are 60mm x 30 mm x 0.1 mm. Inlet velocity is 0.1 m/s. Reynolds number in my case is quite high ~ 20400. Future steps will be adding chemical species in phases and reactions.
But, my simulations are diverging.
Schematics and case files are included.
I have several assumptions about causes that I am checking:
1. The way I defined mesh as consisting of two blocks.
2. Sharp interface between gas and flow causing divergence.

3. Incorrect BCs.


Any help/hints/advises will be appreciated, thanks in advance!

Initial fields:

T.water:
dimensions [0 0 0 1 0 0 0];
internalField uniform 360;
boundaryField
{
inlet_gas
{
type fixedValue;
value $internalField;
}
outlet_gas
{
type inletOutlet;
phi phi.water;
inletValue $internalField;
value $internalField;
}
inlet_liquid
{
type fixedValue;
value $internalField;
}
outlet_liquid
{
type inletOutlet;
phi phi.water;
inletValue $internalField;
value $internalField;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

T.steam:
dimensions [0 0 0 1 0 0 0];
internalField uniform 360;//372.76;
boundaryField
{
inlet_gas
{
type fixedValue;
value $internalField;
}
outlet_gas
{
type inletOutlet;
phi phi.steam;
inletValue $internalField;
value $internalField;
}
inlet_liquid
{
type fixedValue;
value $internalField;
}
outlet_liquid
{
type inletOutlet;
phi phi.steam;
inletValue $internalField;
value $internalField;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

U.water:
dimensions [0 1 -1 0 0 0 0];
internalField uniform (0.1 0 0);
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform (0.1 0 0);
}
outlet_gas
{
type pressureInletOutletVelocity;
phi phi.water;
value $internalField;
}
inlet_liquid
{
type fixedValue;
value uniform (0.1 0 0);
}
outlet_liquid
{
type pressureInletOutletVelocity;
phi phi.water;
value $internalField;
}
top_gas
{
type noSlip;
}
bottom_liquid
{
type noSlip;
}
}

U.steam:
dimensions [0 1 -1 0 0 0 0];
internalField uniform (0.1 0 0);
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform (0.1 0 0);
}
outlet_gas
{
type pressureInletOutletVelocity;
phi phi.steam;
value $internalField;
}
inlet_liquid
{
type fixedValue;
value uniform (0.1 0 0);
}
outlet_liquid
{
type pressureInletOutletVelocity;
phi phi.steam;
value $internalField;
}
top_gas
{
type noSlip;
}
bottom_liquid
{
type noSlip;
}
}

p:
dimensions [ 1 -1 -2 0 0 0 0 ];
internalField uniform 1e5;
boundaryField
{
inlet_gas
{
type calculated;
value $internalField;
}
outlet_gas
{
type calculated;
value $internalField;
}
inlet_liquid
{
type calculated;
value $internalField;
}
outlet_liquid
{
type calculated;
value $internalField;
}
top_gas
{
type calculated;
value $internalField;
}
bottom_liquid
{
type calculated;
value $internalField;
}
}

p_rgh:
dimensions [ 1 -1 -2 0 0 0 0 ];
internalField uniform 1e5;
boundaryField
{
inlet_gas
{
type fixedFluxPressure;
value $internalField;
}
outlet_gas
{
type prghPressure;
p $internalField;
value $internalField;
}
inlet_liquid
{
type fixedFluxPressure;
value $internalField;
}
outlet_liquid
{
type prghPressure;
p $internalField;
value $internalField;
}
top_gas
{
type fixedFluxPressure;
value $internalField;
}
bottom_liquid
{
type fixedFluxPressure;
value $internalField;
}
}

water.water:
dimensions [0 0 0 0 0 0 0];
internalField uniform 1;
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform 0;
}
outlet_gas
{
type inletOutlet;
phi phi.water;
inletValue uniform 0;
// value $internalField;
}
inlet_liquid
{
type fixedValue;
value uniform 1;
}
outlet_liquid
{
type inletOutlet;
phi phi.water;
inletValue $internalField;
value $internalField;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

water.steam:
dimensions [0 0 0 0 0 0 0];
internalField uniform 1;
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform 1;
}
outlet_gas
{
type inletOutlet;
phi phi.steam;
inletValue $internalField;
value $internalField;
}
inlet_liquid
{
type fixedValue;
value uniform 0;
}
outlet_liquid
{
type inletOutlet;
phi phi.steam;
inletValue uniform 0;
// value $internalField;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

alpha.water:
dimensions [0 0 0 0 0 0 0];
internalField uniform 0;
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform 0;
}
outlet_gas
{
type inletOutlet;
phi phi.water;
inletValue uniform 0;
value uniform 0;
}
inlet_liquid
{
type fixedValue;
value uniform 1;
}
outlet_liquid
{
type inletOutlet;
phi phi.water;
inletValue uniform 1;
value uniform 1;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

alpha.steam:
dimensions [0 0 0 0 0 0 0];
internalField uniform 1;
boundaryField
{
inlet_gas
{
type fixedValue;
value uniform 1;
}
outlet_gas
{
type inletOutlet;
phi phi.steam;
inletValue uniform 1;
value uniform 1;
}
inlet_liquid
{
type fixedValue;
value uniform 0;
}
outlet_liquid
{
type inletOutlet;
phi phi.steam;
inletValue uniform 0;
value uniform 0;
}
top_gas
{
type zeroGradient;
}
bottom_liquid
{
type zeroGradient;
}
}

nut:
dimensions [0 2 -1 0 0 0 0];
internalField uniform 1e-8;
boundaryField
{
inlet_gas
{
type calculated;
value $internalField;
}
outlet_gas
{
type calculated;
value $internalField;
}
inlet_liquid
{
type calculated;
value $internalField;
}
outlet_liquid
{
type calculated;
value $internalField;
}
top_gas
{
type nutkWallFunction;
value $internalField;
}
bottom_liquid
{
type nutkWallFunction;
value $internalField;
}
}

Attached Images
File Type: png schematics.png (18.8 KB, 24 views)
Attached Files
File Type: zip 2domain2Dcase.zip (17.3 KB, 1 views)
tonnykz is offline   Reply With Quote

Old   March 13, 2019, 14:04
Default
  #2
New Member
 
Join Date: Oct 2016
Posts: 29
Rep Power: 6
tonnykz is on a distinguished road
I think I found an answer to my question from this Boundary conditions for Two-phase Flow with Different Inlet Pressures thread.
As I've been imposing different BC for two regions there is always the gradient of field. Therefore, my simulations kept diverging.
Now, I moved to formulation of single region (as single 2D pipe), and took the injection and fluidisedBed tutorials from multiphase/reactingTwoPhaseEulerFoam/laminar in OF6.

Hope that will help someone.
BlnPhoenix likes this.
tonnykz is offline   Reply With Quote

Old   June 15, 2020, 02:09
Default
  #3
New Member
 
yizzfaa
Join Date: Jan 2020
Posts: 1
Rep Power: 0
yizzf is on a distinguished road
Quote:
Originally Posted by tonnykz View Post
I think I found an answer to my question from this Boundary conditions for Two-phase Flow with Different Inlet Pressures thread.
As I've been imposing different BC for two regions there is always the gradient of field. Therefore, my simulations kept diverging.
Now, I moved to formulation of single region (as single 2D pipe), and took the injection and fluidisedBed tutorials from multiphase/reactingTwoPhaseEulerFoam/laminar in OF6.

Hope that will help someone.
Thanks for helping me too
yizzf is offline   Reply With Quote

Reply

Tags
chemistry, multiphase flow, reactingtwophaseeulerfoam

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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



All times are GMT -4. The time now is 02:32.