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-   -   Why? Preferred droplet track in Two-Phase flows (https://www.cfd-online.com/Forums/siemens/52350-why-preferred-droplet-track-two-phase-flows.html)

Maurice Kettner February 2, 2000 05:39

Why? Preferred droplet track in Two-Phase flows
 
We have analized droplet tracks simulated with the lagrange model in Star-CD and we have found preferred direction of the moving droplets, which fly vantaged through cellcenters and avoid crossing cellborders if there is a small angle between droplet motion and cell orientation. What is the reason for this effect? Thank you for your help. Maurice

Joern Beilke February 7, 2000 15:48

Re: Why? Preferred droplet track in Two-Phase flows
 
There is at least a simple workaround for this (long known) problem. Just use a highly irregular mesh (tets).

David Schmidt March 31, 2000 18:00

Re: Why? Preferred droplet track in Two-Phase flows
 
Maurice,

Do you have droplet collisions turned on? If so, that could be the cause. I assume Star uses a droplet collision algorithm like O'Rourke's in Kiva. In this model, only droplets within the same call can collide. The collisions either result in coalesence or inelastic bouncing. In either case, the result is to turn droplet trajectories away from the sides of cells and towards cell centers. I have a paper under review by the Journal of Computational Physics that documents this problem in Kiva, if you are interested.

Regards, David Schmidt

Mori-Nik March 15, 2011 06:54

Hi David,

I am tryng to implement the other possibilties of collisions in KVIA, I was wondering if you know I should introduce the new satelite drops to KIVA, grateful for any help?

mel021184 January 3, 2012 11:25

examples for kiva 3V or kiva 4.
 
Hi, I'm working with kiva 3V.

I need examples for kiva 3V or kiva 4.
non engine application.
someone who can help me?
someone who has worked with kiva 3v or kiva4?
I'm trying to simulate a spray impacting on a surface.


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