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

Jet simulation using pimplefoam(LES)0OF2112

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 7, 2022, 02:29
Default Jet simulation using pimplefoam(LES)0OF2112
  #1
Senior Member
 
Farzad Faraji
Join Date: Nov 2019
Posts: 206
Rep Power: 8
farzadmech is on a distinguished road
Hello all
I am using pimpleFoam(LES) to simulate water jet. My mesh is good and it can resolve the jet, but I need to add synthetic turbulence in to nozzle jet since it is to strong and coherent without entrance turbulence. I am using OF2112, U(especially turbulentDFSEMInlet)and P boundary conditions as I put in below.
With 10% turbulence intensity, my jet is still very coherent and does not dissipate as I attached the jet figure to this thread. what should I do? Are mt Turbulence Intensity parameter defined logically?
Nozzle diameter = 0.005 m
Nozzle velocity = 0.64 m/s

Boundary conditions for Nozzle_Outlet (turbulentDFSEMInlet);

Code:
 Nozzle_Outlet
    {
    type            turbulentDFSEMInlet;
    delta           0.005; // 1*0.005; //Characteristic length scale	

    
     R    uniform (0.004096 0.0 0.0 0.004096 0.0 0.004096);     // 10%*0.64==>0.064=======>0.064^2=0.004096
        
     U               uniform (0.0 0.64 0.0);
     value	      uniform (0.0 0.64 0.0);
        
     L               uniform 0.001;   // 0.2*0.005=0.001

     nCellPerEddy    2;
		
    }
Boundary conditions for Velocity;

Code:
/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    location    "0";
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    TopWall
    {
        type            inletOutlet;
        inletValue      uniform (0 0 0);
        value           uniform (0 0 0);
    }
    fixedWalls
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    Nozzle_solidBodys
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    Nozzle_Outlet
    {
    type            turbulentDFSEMInlet;
    delta           0.005; // 1*0.005; //Characteristic length scale	

    
     R               uniform (0.004096 0.0 0.0 0.004096 0.0 0.004096);     // 10%*0.64==>0.064=======>0.064^2=0.004096
        
     U               uniform (0.0 0.64 0.0);
     value	      uniform (0.0 0.64 0.0);
        
     L               uniform 0.001;   // 0.2*0.005=0.001

     nCellPerEddy    2;
		
    }
}


// ************************************************************************* //
And for pressure, we have below boundary condition;
Code:
/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    TopWall
    {
        type            fixedMean;
        meanValue       constant 0;
        value           uniform 0;
    }
    fixedWalls
    {
        type            fixedFluxPressure;
        gradient        uniform 0;
        value           uniform 0;
    }
    Nozzle_solidBodys
    {
        type            fixedFluxPressure;
        gradient        uniform 0;
        value           uniform 0;
    }
    Nozzle_Outlet
    {
        type            zeroGradient;
    }
}


// ************************************************************************* //
Thanks,
Farzad
Attached Images
File Type: jpg photo_2022-07-07_00-15-33.jpg (50.0 KB, 31 views)
farzadmech is offline   Reply With Quote

Reply

Tags
jet, les, openfoam, pimplefoam, turbulence intensity


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


Similar Threads
Thread Thread Starter Forum Replies Last Post
simple Liquid jet simulation in an open domain canev.civelek FLUENT 3 January 23, 2024 00:20
Jet fan and Tunnel simulation ahlo7 CFX 9 November 13, 2019 05:54
Jet spray simulation, which solver we have to use virothi Main CFD Forum 9 December 28, 2018 16:25
2D LES simulation of turbulent jet adnan.nweilati FLUENT 6 December 3, 2014 10:33
2D LES simulation of turbulent jet adnan.nweilati FLUENT 0 November 12, 2014 11:50


All times are GMT -4. The time now is 12:55.