an important part of setting up the CFD
simulation is configuring the settings
for numerical schemes which are made in
the FV schemes file the file is located
in the system directory which I can list
here for the case i'm currently running
i can look inside the file by opening in
an editor or by scrolling through it in
the terminal with the less command as
you can see here i hit the space bar to
scroll like so and if I need to I use Q
to quit I can see the settings for
specific terms and equations for example
diff Phi K gives me the disc realization
of advection of turbulent kinetic energy
in this case the scheme is limited
linear the question users often asked is
what other choices of schemes are there
one way to get an idea of recommended
schemes is to look through the tutorials
examples and look in the settings for
all cases by hand this would be
time-consuming but to speed things up we
can use foam search get help with foam
search by the minus H option you can see
that you need to provide the name of the
file you want to search in the directory
in which to search for files of that
name and the keyword you're interested
in so if we want to search through all
the tutorials we give it the tutorials
directory we can use the foam tutorials
environment very variable for that then
we have the keyword which must include
the names of sub dictionaries that the
keyword is inside here we want to search
for diff I k in div schemes so we need
do schemes dot do fight k then we add
the file name which is FV schemes and we
hit return
now this lists all the unique choices of
defy k so providing a list of all you
schemes to see which schemes are most
commonly used we can run the command
again but this time with the minus C or
count option and this displays the
number of instances of each scheme hear
it clearly shows that limited linear
with 26 and upwind with 37 are the most
used schemes these then provide the safe
choices of schemes for this term which
the user can try and there are the
convenience