Author Topic: Question about virtual grid for turbulentDFMInlet  (Read 6643 times)


  • Newbie
  • *
  • Posts: 18
    • View Profile
Question about virtual grid for turbulentDFMInlet
« on: February 04, 2021, 11:41:40 PM »
For the gridFactor, I use the default value (=1). For my inlet grid, the smallest grid area is 7.8125e-5 m^2. From the documentation “gridFactor entry defines ratio between the virtual grid spacing Δ with the square root of the area of the smallest face element on the inflow plane”, the virtual grid spacing Δ would be square root of 7.8125e-5 ~ 0.0088 m. Since my inlet plane is 4 m by 3 m, I expect there will be 4/0.0088 = 454 grids in the y-direction and 3/0.0088 = 341 grids in the z-direction, meaning there will be 454*341=154814 grids in the virtual grid. However, when I run pisoFoam, the output states “Generating Inflow for 25440 faces”. Does this mean there are only 25440 grids in the virtual grid? Is it possible to view the virtual grid, or output the coordinates of the virtual grids generated by TInF? Thank you.


  • Administrator
  • Full Member
  • *****
  • Posts: 232
    • View Profile
Re: Question about virtual grid for turbulentDFMInlet
« Reply #1 on: February 05, 2021, 12:19:15 AM »
The output status “Generating Inflow for 25440 faces” indicates there are a total of 25440 face elements on your inlet patch rather than the number of virtual grid nodes created. It is indeed possible to visualize the virtual grid by outputting the whole virtual grid system as a surface mesh and visualizing it using Paraview.  We will look into saving the grid fro viewing in paraview.