Adding effect of gravity

[Ajay Rawat]

Dear All,

I'm interested in understanding the role of gravity during the atomisation problem. Here is a snippet of code that includes gravity.

/**
 * Add acceleration due to gravity
 */
event acceleration (i++) {
    face vector av = a;
    foreach_face(x)
        av.x[] += 9.81;
}

Is it okay to include gravity like this? I'm following the atomization (Basilisk - src/examples/atomisation.c) example to develop my code.

Thanks in advance.

With regards
Ajay RAWAT

[Edoardo Cipriano]

Dear Ajay,

Yes it looks good. Alternatively, for incompressible two-phase flow simulations, you can use the reduced.h approach:

http://www.basilisk.fr/src/reduced.h

which expresses gravity as an interfacial force. Using this approach you just have to provide the value of:

G.x = 9.81;

without adding any additional event. At the bottom of the reduced.h file you can find a bunch of examples.

PS: I don't know if the specific gravity value that you are using is coherent with the dimensions of the atomization.c problem.

Hope this helps,

Edoardo