[kavatar]

Hello All,

I am developing a Magneto-hydrodynamic (MHD) solver which reads an externally applied rotating magnetic field (RMF). The magnetic field complete one rotation in one second.

I have generated the rotating magnetic field data for one second using a third party software and stored the field distribution at discrete times in time directories/folders. i.e. 0/0.1/0.2/………0.9/1.

(Point-1:- For time 0 to 1 second)) Now I want to use this magnetic field such that, between time 0 and 0.1 solver uses data stored in 0 directory and between time 0.1 and 0.2 solver uses data stored in 0.1 directory and so on.

(Point-2:- For time >1 second) And since magnetic field is rotating, it repeats after one second so between time 1 and 1.1 solver should use magnetic field stored in directory 0 and between time 1.1 and 1.2 solver should use field stored in directory 0.1. And so on….

Solution for Point 1:- I could perform calculation for time<1 second (Point 1) by below mentioned piece of code written in solver (not in the createFields file). And it works fine within this time interval.

IOobject BHeader
(
"B0",
runTime.timeName(),
mesh,
IOobject::NO_READ
);

if (BHeader.typeHeaderOk<volVectorField>(true))
{
volVectorField BNew
(
IOobject
(
"B0",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::NO_WRITE
),
mesh
);

B0 = BNew;
}

Here B0 is original volumeVectorField stored at 0 and is declared in createFields. As solver reaches a particular time it search for the folder with timeName and check if it contains the field B0. If the folder contains the field it will replace the original B0 with BNew.

Now my question is for time>1 (Point-2) i.e. At time 1.1, I want to read the variable stored in folder/directory 0.1 and similarly at time 1.2 read variable stored in folder 0.2 and so on. Can anyone help me with this point?

(I can perform the calculation by making folder named 1.1, 1.2, 1.3 and so on. And the solver will read the field just like it read for time<1. But, I don’t want to do this since my simulation will run for almost 300 seconds and for that I will have to make so many folders)

Thanks in advance

[kavatar]

Hello,

I solved this problem on my own with following steps:

- scalar A=float value of time
- label B=int value of time
- scalar C=A-B;
- string D=std::to_string(C);

This will give me the value between 0 to 1 for current time.

I stored the files in a folder named "B" and read them from that folder at every time step using the code:

IOobject BHeader
(
D,
"B",
mesh,
IOobject::NO_READ
);

if (BHeader.typeHeaderOk<volVectorField>(true))
{
volVectorField BNew
(
IOobject
(
D,
"B",
mesh,
IOobject::MUST_READ,
IOobject::NO_WRITE
),
mesh
);

B0 = BNew;
}

Thanks !!