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Apply deltaT in utility

Dear all,

At the moment I am trying to modify a utility file, where I want to multiply a constant by deltaT. I use a fixed Courant number, so I do not know the time step beforehand.

I have tried the following:
alpha=C*runTime.deltaT().value();
where alpha is the expression I want to modify, and C is a constant.

When I recompile the utility I get the following error message: error: ‘runTime’ was not declared in this scope.

I know there is not much information in the post, but if anybody could give me an advise on how to declare runTime, it will be appreciated.

Kind regards,
Bo Terp

Ps. I am using OF 1.5-dev

Hi Bo Terp,

have a look at /applications/utilities/postProcessing/wall/wallGradU/wallGradU.C for example.

Here is a code snippet that shows how to access the time values:

Code:

    ... header from wallGradU.C ...

int main(int argc, char *argv[])

{

    timeSelector::addOptions();

    #include "setRootCase.H"

#   include "createTime.H"

    instantList timeDirs = timeSelector::select0(runTime, args);

#   include "createMesh.H"



    scalar lastTimeStep = 0; // added

    scalar deltaTime = 0; // added

    forAll(timeDirs, timeI)

    {

        runTime.setTime(timeDirs[timeI], timeI);

        deltaTime = timeDirs[timeI].value() - lastTimeStep; // added

        lastTimeStep = timeDirs[timeI].value(); // added



        Info<< "Time = " << runTime.timeName() << endl;

        Info<< "deltaT = " << deltaTime << endl; // added



        ... more code ...

Martin