Question about data mapping from solid solver to fluid solver

Using preCICE
7

Sorry for deleting the previous wrong results since there are some mistakes in case setting. After modifing the case setting for our solid solver and modifying the preciceDict according to @Michael , the case works fine even though the pressures are still smaller than expected (due to mapping?). I’m refering to Mapping Configuration and the topic How does precice use meshes for mapping and communication, however, I have a few more questions to ask.

  1. In partitioned-pipe case, the locations where to exchange Pressure and ‘Velocity’ are not defined.
    preciceDict_partitioned-pipe.txt (437 Bytes)
    For Pressure and Velocity, should we exchange these kind of data on faceCenters or faceNodes?
  2. At present, I exchange Pressure on faceCenters, Displacement and Velocity on faceNodes.
    precice-config.xml (3.0 KB)
    preciceDict.txt (735 Bytes)
    preCICE-output in solid part:
    Fluid-Mesh-Centers-Solid.dt1.txt (5.1 KB)
    Fluid-Mesh-Nodes-Solid.dt1.txt (10.8 KB)
    Solid-Mesh-Solid.dt1.txt (5.6 KB)
    For preCICE-output in solid part, Fluid-Mesh-Centers-Solid.dt*.vtk contains the coordinates of fluid cell face centers and pressures. The pressures in this file are interpolated by the pressures in Fluid-Mesh-Centers-Fluid.dt1_r*.vtu, right? For Fluid-Mesh-Nodes-Solid.dt*.vtk, it contains the coordinates of fluid cell nodes but all the variables are zero, why? Additionally, for Solid-Mesh-Solid.dt*.vtk, it includes the coordinates of all solid face nodes, pressures (mapped from Fluid-Mesh-Centers-Fluid.dt1_r* or Fluid-Mesh-Centers-Solid.dt1?)
    preCICE-output in fluid part:
    Fluid-Mesh-Centers-Fluid.dt1_r0.txt (2.0 KB)
    Fluid-Mesh-Centers-Fluid.dt1_r1.txt (2.0 KB)
    Fluid-Mesh-Nodes-Fluid.dt1_r0.txt (3.2 KB)
    Fluid-Mesh-Nodes-Fluid.dt1_r1.txt (3.2 KB)
    Solid-Mesh-Fluid.dt1_r0.txt (3.1 KB)
    Solid-Mesh-Fluid.dt1_r1.txt (2.9 KB)
    For preCICE-output in fluid part, Fluid-Mesh-Centers-Fluid.dt1_r* contains all the pressures on faceCenters and Fluid-Mesh-Nodes-Fluid.dt1_r* contains all the displacements and velocities on fluid faceNodes. The pressures here are directly obtained from OpenFOAM by interpolation from volume center to face certer, and the displacements and velocities here are interpolated from the data in Solid-Mesh-Fluid.dt1_r*, right?
  3. In fluid part, there are repetitive points and data in files such as Solid-Mesh-Fluid.dt1_r0 and Solid-Mesh-Fluid.dt1_r1. Is it a kind of method preCICE handling data mapping or anything wrong in my case setting?
  4. AFAIK, OpenFOAM stores and calculates variables at volume centers. I also wonder if it is OpenFOAM itself or preCICE that does the interpolation from face centers to volume centers (or from face nodes to volume centers) when I read variables from solid solver by faceCenters (or faceNodes). If it is preCICE, since preCICE only has the values on the interface, the data at the volume centers seems to be the extrapolation from the face centers or face nodes, which may be not so accurate. If it is OpenFOAM, since it has both the data of inner cells and the values on the interface, the value at the volume center can be interpolated well.
    If my understanding is wrong, please point it out. Any suggestions will be appreciated!

Best,
Stan