The main concept of the externalComm library is similar to the FMI Standard and it can be viewed as blackbox with time-dependent input and output values and parameters that are fixed in time.

Usage

add to OpenFOAM

add following library to the controlDict

libs(externalComm)

input

    // create new entry
    const Time& runTime = mesh_.time(); // we need the singleton time
    commDataLayer& data = commDataLayer::New(runTime);

    scalar varName = "varName";
    scalar varValue = "varValue";

    data.storeObj(varValue,varName,commDataLayer::causality::in);

    // work with data
    commDataLayer& data = commDataLayer::New(runTime);
    // get varName from registry
    scalar& val = data.getObj<scalar>("varName",commDataLayer::causality::in);
    val = newValue;

output

    // create new entry
    const Time& runTime = mesh_.time(); // we need the singleton time
    commDataLayer& data = commDataLayer::New(runTime);

    scalar varName2 = "varName2"; 
    
    vector varValue2(0,0,0); 
    data.storeObj(varValue2,varName2,commDataLayer::causality::out);

    // work with data
    commDataLayer& data = commDataLayer::New(runTime);
    // get varName2 from registry
    vector& val2 = data.getObj<vector>("varName2",commDataLayer::causality::out); 
    val2 = newValue;

Implementation

Data

As hinted above the approach is similar to FMI standard with the categorization of variables in 3 causality:

• input -> changes in time (and space)
• output -> changes in time (and space)
• parameter -> constant in time (and space)

The core class commDataLayer creates 3 objectRegistries one for each causality that are accessible with an enum:

• commDataLayer::causality::in
• commDataLayer::causality::parameter
• commDataLayer::causality::out

Each of these objectRegistries store and manage the objects passed to them. The elements in the objectsRegistry can be accessed similar to a hashtable. The data is stored in the template class registeredObject<Type> which currently features following Types:

• Primitive Types:
  • bool -> FMI 2.0
  • word -> FMI 2.0
  • label -> FMI 2.0
  • scalar -> FMI 2.0
  • vector
  • symmTensor
  • sphericalTensor
  • tensor
• Fields:
  • Field<scalar>
  • Field<vector>
  • Field<symmTensor>
  • Field<sphericalTensor>
  • Field<tensor>

Comm

Websocket

Zmq

grpc

Json

example