[arieljeds]

Hi all,

I am running free surface flow around a vertical surface piercing cylinder. I am having no trouble for longer wavelengths (smaller diameter to wavelength ratio) but am having a lot of trouble for a short wavelength (wavelength = 2.4 m, diameter = 0.5, waveheight = 0.25).

I am trying to use minimum 50 cells per wavelength and 8 per wave height, which have been plenty for previous simulations.

My constant/waveProperties.input file looks like this:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  1.5                                   |
|   \\  /    A nd           | Web:      http://www.OpenFOAM.org               |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      environmentalProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

seaLevel	0.00;

// A list of the relaxation zones in the simulation. The parameters are given
// in <name>Coeffs below.
relaxationNames (inlet outlet);

initializationName outlet;

//pName		   p_rgh;
inletCoeffs
{
    //waveType        potentialCurrent;
    //U               ( 0.6 0 0 );
    //Tsoft           0;
    
    waveType		stokesFirst;       	// Regular waves
    depth		2.5; 			// Water Depth 
    period		1.25;	 		// Wave period
    phi			0.00000;		// Phase
    direction		(1.0 0.0 0.0);		// Direction of incoming waves
    height		0.25;			// Wave height in meters
    Tsoft		0.0; 
   
    
    relaxationZone
    {
	relaxationScheme Spatial;
        relaxationShape  Rectangular;
        beachType        Empty;
        alphaCoefficient 1;
    
        relaxType   INLET;
        startX      ( -7.2 -3.5    0.0);
        endX        ( -3.6  3.5     0.0);
        orientation      (1.0 0.0 0.0);
    }
};




outletCoeffs
{
    waveType    potentialCurrent;
    U           (0 0 0);
    Tsoft       0;

    relaxationZone
    {
        relaxationScheme Spatial;
        relaxationShape  Rectangular;
        beachType        Empty;  
        alphaCoefficient 1;  

        relaxType   OUTLET;
        startX      (  4.5 -3.5    0.0);
        endX        (  7.2  3.5   0.0);
        orientation      (1.0 0.0 0.0);
    }
};


// ************************************************************************* //

The issue appears to be with the mesh (or perhaps the relaxation zones??) but the mesh isn't too bad (max aspect ratio 5.6, see attached image). I've attached an image of the contour plot of velocity at alpha.water = 0.5.

Any advice on what could be causing these problems??

[Narayan_UD]

Hi , which software you are using for visualization ?