[taajaki]

Hi Foamers.
I am trying to simulate a micro channel and I expect to see droplets in it but as you can see here the droplets are not formed . Blue color is oil(continuous phase) in main channel and the red one is water (dispersed phase) which is flow in two lateral channels.(I have two lateral channel and one main channel).
Is there any comment ?
thanks for your attention
these are boundary conditions :
alpha.water

boundaryField
{
   oil
    {
        type            fixedValue;
	value		uniform 0.0;
    }
    water-1
    {
        type            fixedValue;
	value		uniform 1.0;
    }
     water-2
    {
        type            fixedValue;
	value		uniform 1.0;
    }
   outlet
    {
        type            zeroGradient;
    }

    walls
    {
        type            zeroGradient;
    }
 

    defaultFaces
    {
        type            empty;
    }


}

alpha.water.org

internalField   uniform 0;

boundaryField
{
   oil
    {
        type            fixedValue;
	value		uniform 0.0;
    }
    water-1
    {
        type            fixedValue;
	value		uniform 1.0;
    }
     water-2
    {
        type            fixedValue;
	value		uniform 1.0;
    }
    outlet
    {
        type            zeroGradient;
    }

    walls
    {
        type            zeroGradient;
    }
 

    defaultFaces
    {
        type            empty;
    }


}

p_rgh

internalField   uniform 0;

boundaryField
{
    oil
    {
        type            zeroGradient;
    }
    water-1
    {
        type            zeroGradient;
    }
    water-2
    {
        type            zeroGradient;
    }
    outlet
    {
        type            fixedValue;
	value		uniform 0;
    }

    walls
    {
        type            zeroGradient;
    }

   
}

U

boundaryField
{
   oil 
    {
        type            fixedValue;
        value           uniform (0.01386 0 0);

    }
    
    water-1
    {
        type            fixedValue;
        value           uniform (0 -0.011 0);
    }
    water-2
    {
        type            fixedValue;
        value           uniform (0 -0.011 0);
    }

    outlet
    {
        type		zeroGradient;
    }

    walls
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }

}

[taajaki]

hi everyone
this is my third question in succession that none of them were answered however I hope to find the solution and post it here to help others...
I have a micro channel which you can see it here

http://www.cfd-online.com/Forums/ope...o-channel.html

I have a question about defining contact angel in this micro channel hopefully to see droplets in main channel.
1-Is it necessary to define contact angle to making droplets?(boundaries are correct?)
2-Is it suppose to define in main or lateral channels?
3-In which phase should I define it and how?
thank you

[wyldckat]

Greetings taajaki,

Sorry for the late reply, but I only now managed to have a somewhat better look at your questions.

For what I can figure out so far, the VOF approach in OpenFOAM does not yet contemplate micro-fluid behaviour or at least not very well. Here are some threads I've kept some track on regarding this issue, perhaps you can figure out something more from them:

• http://www.cfd-online.com/Forums/ope...lat-plate.html
• http://www.cfd-online.com/Forums/ope...ofluidics.html
• http://www.cfd-online.com/Forums/ope...y-channel.html

Best regards,
Bruno

[taajaki]

thanks for your attention Bruno
could you please take a look at this question: http://www.cfd-online.com/Forums/ope...o-channel.html

thanks alot