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-   -   DieselFoam Droplet Temperature Issues - OF 1.6 (http://www.cfd-online.com/Forums/openfoam/73128-dieselfoam-droplet-temperature-issues-1-6-a.html)

viv05 February 27, 2010 12:20

DieselFoam Droplet Temperature Issues - OF 1.6
 
Hi all,

To people who are interested in dieselFoam

I tried running a case with single droplet to check the evaporation characteristics. (No velocity / gravity / crossflow)

When I output the values of the temperature, mass, diameter, saturation pressure, etc of the droplet, I find this anomaly.

The temperature of the droplet, just before the droplet completely evaporates starts to reduce and falls to negative values (which is offset by the 200K numerical setting in the code - parcel.C )

Why is the temperature of the droplet falling? From other values, such as the "evaporationSource" and "fCorrect" terms, the temperature must rise! (these terms pertain to the characteristic heat transfer and evaporation times).

In Openfoam 1.5, there was a problem where the droplet temperature on boiling used to rise up to the critical temperature of the liquid, and this has been tackled in openfoam 1.6, by not letting the droplet temp. go beyond the boiling temperature of the liquid.

Will there be any similar move to check this present scenario of the temperature falling to negative values?

Please let me know,

Thanks!
Viv


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