Plotting Saturation Temperature

Jannssen · January 19, 2016, 08:45

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, 19:24

does anyone have any of kind of idea ?

it would really be appreciated

Thanks a lot

Jan

ghorrocks · January 27, 2016, 06:36

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, 08:16

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, 17:04

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.

January 19, 2016, 08:45	Plotting Saturation Temperature	#1
Jannssen New Member Jan Join Date: Nov 2015 Location: Germany Posts: 7 Rep Power: 11	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

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Below Saturation Temperature Evaporation	amit.garg	FLUENT	0	May 11, 2015 04:59
Calculation of the Governing Equations	Mihail	CFX	7	September 7, 2014 07:27
Too low temperature at combustor outlet	romekr	FLUENT	2	February 6, 2012 11:02
monitoring point of total temperature	rogbrito	FLUENT	0	June 21, 2009 18:31
chemical reaction - decompostition	La S. Hyuck	CFX	1	May 23, 2001 01:07

January 26, 2016, 19:24		#2
Jannssen New Member Jan Join Date: Nov 2015 Location: Germany Posts: 7 Rep Power: 11	does anyone have any of kind of idea ? it would really be appreciated Thanks a lot Jan

January 27, 2016, 06:36		#3
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,854 Rep Power: 144	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.

January 27, 2016, 08:16		#4
Jannssen New Member Jan Join Date: Nov 2015 Location: Germany Posts: 7 Rep Power: 11	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

January 27, 2016, 17:04		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,854 Rep Power: 144	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.