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2D water droplet fall in InterFoam

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Old   November 21, 2013, 05:12
Default 2D water droplet fall in InterFoam
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Muhanad Fakhri
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Dear foamers,

I am new to OpenFoam, and currently have a task to alter the dambreak case into two different cases:-

1- Falling 2D drop from the dam top to hit the empty bottom
2- Falling 2D drop from the dam top to hit a film of water in the bottom.

my problem:-

Defining the alpha1 phase to the spherical/cylindrical droplet, I used the following two expressions which i feel correct in setFieldsDict:-

25 sphereToCell
26 {
27 centre (0.05 0.1 0.5);
28 radius 0.01;
29 fieldValues
30 (
31 volScalarFieldValue alpha1 1

and:-
25 cylinderToCell
26 {
27 p1 (0.05 0.1 0);
28 p2 (0.05 0.1 0.5);
28 radius 0.01;
29 fieldValues
30 (
31 volScalarFieldValue alpha1 1

in the blockMeshDict, I considered having 3 blocks:- one block for the circular droplet where its bottom is tangible to the dam square top from the centreline, and 2 blocks for the dam, left and right to the tangible point centreline (just consider a sphere sitting on a box in the centre).

now i have 4 vertices for the droplet,6 vertices for the dam (one vertex is shared between the three blocks: the tangible point).

well, i defined my vertices, the three blocks..
when it came to the droplet i defined four circular arcs, each arc passes through a point (i used inscribed equal rectangle in the the circle to determine these points).

I had a challenge on boundary part of the blockMeshDict:

I have walls to describe the dam left, right and bottom wall, as well as atmosphere to describe the top part.

how to describe the droplet in this case? and how to describe its type/values in alpha1 file and U, & P in directory (0)?

Would be grateful for your support..Maybe all the above is incorrect??!

Regards
Muhanad
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Old   November 21, 2013, 07:57
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Muhanad Fakhri
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well, I have maintained everything in the dambreak case and just changed the setFields using cylinderToCell instead of box to cell, and altered the position of the droplet to be inside the domain on the top.

the simulation has captured the droplet fall successfully, just i noticed the slowness of the fall, like if there is a drag preventing it from falling quicker!..

Still need to investigate the situation more closely to find more about the required settings...would appreciate your inputs and discussions on this..
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Old   November 21, 2013, 08:33
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Muhanad Fakhri
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I have now used the refineMesh and got a finer mesh on my droplet, which is supposed to be smaller, the simulation is getting slower really, not falling on real time

still awaiting some comments/ feedbacks on droplet simulation and case setup from your expereinces..
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