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-   -   Plotting Saturation Temperature (https://www.cfd-online.com/Forums/cfx/165514-plotting-saturation-temperature.html)

Jannssen January 19, 2016 07:45

Plotting Saturation Temperature
 
Hi everyone.

I`m trying to simulate flash evaporation of Water due to a sudden pressure-loss.

First I`ve tried to implement an expression for Saturation Temperature and Pressure correlation via Antoine Equation by myself, but I always had issues with negative Total Pressure, since the logarithm of a negative value isn`t defined.

Now I`ve found that the Antoine Equation is already implemented for HBM`s
so I`ve tried that

My Problem now is, that I`m not sure if I`ve got the right Coefficients. Since they differ with every source you look them up.

Is there any way to plot the Saturation Temperatur / Pressure Correlation to validate those Coefficients ?


Thanks a lot !
Jan

Jannssen January 26, 2016 18:24

does anyone have any of kind of idea ?

it would really be appreciated :)

Thanks a lot :)
Jan

ghorrocks January 27, 2016 05:36

Is saturation temperature a variable accessible in the results file? If so you should be able to plot sat temp versus pressure for every node in the domain. This will give you the curve it is following, at least for the range of pressures in your simulation.

Jannssen January 27, 2016 07:16

Hi Glenn. You mean I should try to include it into the transient results file, if possible ?
I`ll make sure to try that.
But what I really meant was to examine this, before starting the Simulation.


Anyways, thanks a lot :)

ghorrocks January 27, 2016 16:04

I cannot see any way to see it without running a simulation. But just running for an iteration or two should be enough to get some sort of curve.


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