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Fire Dynamics Simulator
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Water_evaporation #2422

Closed gforney closed 9 years ago

gforney commented 9 years ago 
Please complete the following lines...

FDS Version:6.0.1
SVN Revision Number:
Compile Date:6/10/2015
Smokeview Version/Revision:
Operating System: Windows 

Describe details of the issue below:
In my evaporation model of water I have used an Initial Region options to define water.
The initial region is enclosed by stainless steal material having opening at the top.
The volume of initial region is .0043 meter cube having a mass of water is 4.35 kg.
I have used heater surface of net heat flux of 12.5 KW/m^2, the area of vent is 0.4m^2.
When i simulate it and obtain the results using Statistics option, the mass fraction
of water is drops from 1.0 to 0.0 in just 3 sec.
How is it possible for 4.35 kg of water.
Enclosing the FDS file and snapshot

Original issue reported on code.google.com by wali.thermal14 on 2015-06-10 07:46:22

gforney commented 9 years ago 
If you are using a species that we have built-in, you should just use the built-in properties
which we have ensured are self-consistent (e.g. just &SPEC ID='WATER VAPOR').

The line:
&INIT MASS_FRACTION=1.0, SPEC_ID='water', XB=4.53,4.67,4.93,5.07,0.91,1.132/ Init Region

is not adding liquid water.  This is putting in water vapor.  If you want to add liquid
droplets you need to put in Lagrangian particles defined with &PART.

The line:
&DEVC ID='[Species: water] Mass Fraction_VOLUME MEAN', QUANTITY='MASS FRACTION', SPEC_ID='water',
STATISTICS='VOLUME MEAN', XB=4.53,4.67,4.93,5.07,0.91,1.132/

would not measure liquid.  It measure the gas. You would need to use the PDPA outputs
for Lagrangian particles.

The reason the mass fraction drops so quickly, is the water vapor is moving out of
that &INIT region and mixing into the rest of the domain.  This is not evaporation.

I reccommend you read the User's Guide and the Verification Guide and look at the many
examples provided with FDS where we use drops (especially the water_evaporation test
cases).

Original issue reported on code.google.com by drjfloyd on 2015-06-10 11:56:46

gforney commented 9 years ago 
&INIT MASS_FRACTION=1.0, SPEC_ID='water', XB=4.53,4.67,4.93,5.07,0.91,1.132/
Init Region

SPEC_ID='water', In this i have provided the properties of liquid water
using Edit Species option, so how the Init Region contain the water vapor
rather than water in liquid phase.
Next thing is that when i calculated the wall clock time from the start of
simulation  to end of water mass fraction in Init Region (i.e mass
fraction=0) it gives a value of 1450 sec with respect to simulation time of
10 sec which is realistic in nature.

Please clear my issue about the Init Region.

Another problem is that I want to trace cooking oil vapor particles and
also I want to filter it. Please guide me in this direction.....

Thanks in advance

Original issue reported on code.google.com by wali.thermal14 on 2015-06-11 05:17:05

gforney commented 9 years ago 
Questions on using fds belong in the discussions forum.  Did you look at the water_evaporation
example cases as I said? Follow those examples.

Original issue reported on code.google.com by drjfloyd on 2015-06-11 10:17:15

gforney commented 9 years ago 
Dear, I want to confirm that FDS only plots the variation of any quantity
in gas phase only?

Yes I follow the example 1 and when I plot the different parameters like
density, humidity, mass fraction then density and humidity increases its
okay but the mass fraction also increases So. it means that it plot the
variation of water vapor only.
I want to plot the variation of mass fraction of water liquid (which is
decreasing in nature).
Plz guide me how to do this and one more thing how to trace water vapor
particles flow in domain and similarly for cooking oil vapors

I am waiting your response.....

Original issue reported on code.google.com by wali.thermal14 on 2015-06-11 17:48:51

gforney commented 9 years ago 
Jason asked you to please post your question to the forum.  This Issue has been marked
invalid.

https://groups.google.com/forum/?fromgroups#!forum/fds-smv

Original issue reported on code.google.com by randy.mcdermott on 2015-06-11 17:52:03

gforney commented 9 years ago 
I am enclosing here my FDS file in which i want to evaporate the water using particle
cloud plz check the file and respond me where I am wrong.

I am waiting....

Original issue reported on code.google.com by wali.thermal14 on 2015-06-11 18:08:24

gforney commented 9 years ago 
Last time, the issue tracker is for bug reports.  Questions on using FDS belong in the
forum.  We will no longer respond to this issue as it is not a bug report.

Original issue reported on code.google.com by drjfloyd on 2015-06-11 18:10:26