[philiplu]

Hello,

does someone know what's the objective of

#sinclude "sampling"
in
controlDict dictionary

from the tutorial
$FOAM TUTORIALS/multiphase/interFoam/laminar/damBreak/damBreak

the tutorial-links:
https://develop.openfoam.com/Develop...amBreak/system


thank you in advance

[snak]

Hi

Some info...
https://www.openfoam.com/documentati...y.html#details

https://www.openfoam.com/documentati...y.html#details

The #sinclude directive (and the #includeIfPresent alias) behaves identically to the #include directive, but does not generate an error if the file does not exist.

And, the #include directive for including a file, expects a single string to follow.

[philiplu]

Hello, snak,
thanks for the reply and sure, it helps.

another concern:
literally I guess
#sinclude "sampling"
ONLY samples data during the solving, WITHOUT any impact on solving results...

As I'm not familiar with the OF-background-mechanism yet, so to rephrase my concern:

#sinclude "sampling" won't influence the results, right?



additionally: 1 question, 1 confirmation:

what's "phirb"?


confirmation:
i.e. pressure, if its input unit is e.g. m2/s2, then that of out-coming results stay still in the same unit (m2/s2), put simply
input in e.g. m2/s2
results still in m2/s2
right?



thank you and OF-friends in advance

[snak]

Originally Posted by philiplu

another concern:
literally I guess
#sinclude "sampling"
ONLY samples data during the solving, WITHOUT any impact on solving results...

As I'm not familiar with the OF-background-mechanism yet, so to rephrase my concern:

#sinclude "sampling" won't influence the results, right?

Yes.
#sinclude itself do nothing. Just copy and paste the content of the file.
In your case (damBreak), "type set" in "sample library" will do its job.
There should be no impact on solving.

Originally Posted by philiplu

additionally: 1 question, 1 confirmation:

what's "phirb"?

phirb is related to a compression velocity.
Details are explained in the PhD thesis by Henrik Rusche. It appears in eq.(4.14).
https://spiral.imperial.ac.uk/handle/10044/1/8110

Originally Posted by philiplu

confirmation:
i.e. pressure, if its input unit is e.g. m2/s2, then that of out-coming results stay still in the same unit (m2/s2), put simply
input in e.g. m2/s2
results still in m2/s2
right?

Yes.
You can check it by looking the output file itself.
A file wrriten as a result also have a line of "dimensions".

[philiplu]

hello, snak,

thanks for your scientifically summarized and clear answers, alleviating my "worry" essentially e.g. that p switches to kgm-1s-2 as output.

as I'm even new i.e. just start, online to post sth, so forgive my further Qs without self-refraining rationally:

Q1:
(still in damBreak case as in preceding posts)
as in the sampling file:
.........................................
sets
(
gauge_1
{
type face;
axis y;
start (0.02 0.20 0.005);
end (0.02 0.25 0.005);
nPoints 100;
}

gauge_2
{
type face;
axis y;
start (0.2 0.03 0.005);
end (0.2 0.55 0.005);
nPoints 100;
.........................................

what's the "nPoints 100"? 100 sample-points between e.g. 0.20-0.25 (0.03-0.55) of y?
anyhow, i checked the output: the output number i.e. number of points are different betwwen gauge_1 and _2 and neither is 100


Q2:
the output-format is vtk, certainly using e.g. python or math-software, even manually excel, the sampling output can be plotted. But paraView must be capable to visualize them.
i tried, individually (in one time step, e.g. one gauge) but without success, so do you or someone knows how to plot them in paraview?

Q3:
still Q2 related, when the time-steps exceeds e.g. 100, how to import them into paraview in batch (if paraview can plot them individually)


thank you and OF-friends in advance


regards

[philiplu]

hello, snak and OFOAM-friends

after an insight of UserGuide, the "face" (an example as in appendix) states:
"Intersection of specified line and cell faces"

then the "nPoints", i.e. "Number of sampling points" (e.g. =100 here) could be overridden, since

number of intersection won't always coincide with the (randomly decided) "Number of sampling points" (e.g. =100 here), right?


thank you and regards



____________________________
appendix:
.........................................
sets
(
gauge_1
{
type face;
axis y;
start (0.02 0.20 0.005);
end (0.02 0.25 0.005);
nPoints 100;
}