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Jay December 20, 2007 03:35

atomization model vs breakup model
Can anybody explain to me the difference btn atomization model and breakup model?

dong December 20, 2007 05:39

Re: atomization model vs breakup model
atomization model - primary breakup, i.e. the breakup of the liquid as it leaves the nozzle

breakup model - secondary breakup, i.e. the further breakup of the droplets due to interaction with the flow field.

Jay December 20, 2007 12:35

Re: atomization model vs breakup model
I mean both model in Star-CD. there are several models of both case in star-cd

So, you mean I can't deal with primary breakup thru breakup model such as Hsiang and Faeth model.

Is that right?

Pauli December 20, 2007 17:30

Re: atomization model vs breakup model

Details regarding the droplet breakup and spray atomization models are described in section 12 of the version 3.26 methodology manual.

If you don't like what's built into the code, you might be able to code you own algorithms via user subroutines. I've never tried this so I'm not sure exactly how far you can go.

Jay December 21, 2007 01:50

Re: atomization model vs breakup model
Actually I have Star-cd ver.3.24

Pauli, would u like to send the ver.3.26 methodology?

Pauli December 21, 2007 20:32

Re: atomization model vs breakup model
Sorry but tha's copyrighted material.

You should have a copy in your installation. If not, it's on the installation disks. It's a PDF file. It should be installed at:


You will need to replace 3.26.008 with your version.

Andrea January 24, 2008 20:41

Re: atomization model vs breakup model
Hi Jay,
you can find detailed description of model also on literature...and also in old metodology books from Cd-Adapco! I use ver 3.26 too and I have that met. but a detailed and sufficient description of breakup/atomization models it's also present on metodology ver 3.22...hope it's tha same for ver 3.24!
There aren't any big changes in those models...

Andrea January 24, 2008 20:51

Re: atomization model vs breakup model
Well, if you're interested in a model that predict the atomization process and also the secondary breakup, just try to use the Reitz-Diwakar models for those subjects. It's a model that can be extended from atomization to secondary you don't need to modify many constants...
Hope that helps you...

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