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an important part of setting up the CFD

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simulation is configuring the settings

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for numerical schemes which are made in

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the FV schemes file the file is located

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in the system directory which I can list

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here for the case i'm currently running

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i can look inside the file by opening in

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an editor or by scrolling through it in

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the terminal with the less command as

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you can see here i hit the space bar to

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scroll like so and if I need to I use Q

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to quit I can see the settings for

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specific terms and equations for example

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diff Phi K gives me the disc realization

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of advection of turbulent kinetic energy

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in this case the scheme is limited

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linear the question users often asked is

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what other choices of schemes are there

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one way to get an idea of recommended

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schemes is to look through the tutorials

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examples and look in the settings for

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all cases by hand this would be

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time-consuming but to speed things up we

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can use foam search get help with foam

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search by the minus H option you can see

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that you need to provide the name of the

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file you want to search in the directory

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in which to search for files of that

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name and the keyword you're interested

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in so if we want to search through all

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the tutorials we give it the tutorials

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directory we can use the foam tutorials

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environment very variable for that then

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we have the keyword which must include

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the names of sub dictionaries that the

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keyword is inside here we want to search

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for diff I k in div schemes so we need

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do schemes dot do fight k then we add

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the file name which is FV schemes and we

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hit return

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now this lists all the unique choices of

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defy k so providing a list of all you

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schemes to see which schemes are most

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commonly used we can run the command

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again but this time with the minus C or

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count option and this displays the

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number of instances of each scheme hear

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it clearly shows that limited linear

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with 26 and upwind with 37 are the most

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used schemes these then provide the safe

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choices of schemes for this term which

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the user can try and there are the

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convenience