[NotOverUnderated]

Hello,

I am using OpenFOAM v2306. I wonder if it is possible to use expressions or Function1 to set the values in controlDict, here is what I mean:

adjustTimeModifiable  true;
maxCo       foo; <<< I want to adjust this using a table of values or using expression

I want to use a value for foo that depends on the simulation time, t, for example:

• foo = 0.5 for t < 0.7 .
• foo = 1.5 for 0.7 < t < 1.3
• foo = 2.0 for t > 1.3

Please note that I am aware of the timeActivatedFileUpdate function object (which is in my exprience becomes quickly confusing, and it is error prone) or using the coded function object to adjust some parameters by using C++ code.

The reasons why I don't like using coded Function object:

• It is not clean, and the file becomes quickly hard to read, and requires the user to write C++ code which is in most cases tricky to get right.
• Sometimes I have very good reasons to use OpenFOAM on Windows with the native mingw installation which does not support compiling code. Also I don't have WSL2 installed for good reasons too.

So my questions are:

• Is it possible to use Function1 table in controlDict to adjust values?
• Is it possible to use expressions(see link below) ?

any help is appreciated


Link to expressions: https://www.openfoam.com/documentati...on-syntax.html

[olesen]

There obviously isn't a trivial way for that at the moment. In general, it should be somewhat doable since controlDict is used almost exclusively by Time, which means it would be possible to have access to a registry and define a Function1 (constant, table, expression, whatever).
It is probably worth taking a look at solution.H, solution.C in OpenFOAM-v2112 or later (commit 53e8f2a807b). There is support for regular Function1 handling for relaxation, which is a similar idea to what you are asking, but it also has a slightly clever approach of caching various Function1 items so that they are only created on-demand once (per field).