How to access Spreadsheet data

Hello everyone!

I have used OpenFOAM for a CFD simulation and right now I am manually trying to obtain the data I need. One of those is the Area averaged Velocity:
In order:

  • I have used the slice tool to get the area of interest
  • Used the “generate Surface normal” filter
  • Calculated with the calculator filter the quantity abs(U.Normals)
  • Implemented an integration by means of “IntegrateVariables”, activating the “divide per cell area/volume” function

I can correctly compute the area averaged velocity, but I need to isolate the value from the spreadsheet row in order to use this value in successive operations.

How can I do that?

thanks in advance for your help :slight_smile:

Do you want to use the value as a property value in a filter? That’s not easy, I’m afraid.

Or do you want to use it in a subsequent filtering operation? You can use the Programmable Filter to access the value in the table.

Hi and thank you for your very fast reply! I need it in order to calculate a flow uniformity index. I used the Catalyst script generator. Ideally, I would like to select a 2D Surface (a slice) and to obtain a flow uniformity index. The script generated by catalyst is the following:

create a new ‘Generate Surface Normals’

generateSurfaceNormals = GenerateSurfaceNormals(Input=slice)

create a new ‘Calculator’

phiCalc = Calculator(Input=generateSurfaceNormals)
phiCalc.ResultArrayName = ‘phiCalc’
phiCalc.Function = 'abs(mag(U)-UavgAveraged

create a new ‘Calculator’

uavg = Calculator(Input=generateSurfaceNormals)
uavg.ResultArrayName = ‘Uavg’
uavg.Function = ‘abs(U.Normals)’

create a new ‘Point Data to Cell Data’

pointDatatoCellData1 = PointDatatoCellData(Input=uavg)

create a new ‘Integrate Variables’

integrateVariables1 = IntegrateVariables(Input=pointDatatoCellData1)
integrateVariables1.DivideCellDataByVolume = 1

create a new ‘Point Data to Cell Data’

pointDatatoCellData2 = PointDatatoCellData(Input=phiCalc)

create a new ‘Integrate Variables’

integrateVariables2 = IntegrateVariables(Input=pointDatatoCellData2)

From the final integration the area averaged phiCalc (let’s say phiCalcAveraged) should be collected, in order to compute:


How can I implement it?:slight_smile:

Sorry for the delay in response.

You’ll need to Fetch the results of the integrate variables filter from the server proxy layer and use them in the expression. It’ll look like this:

from vtkmodules.numpy_interface import dataset_adapter as dsa
local_integrateVariables1 = dsa.WrapDataObject(servermanager.Fetch(integrateVariables1))
UavgAveraged = local_integrateVariables1.CellData['Uavg'][0]

You’ll do the same for the second Integrate Variables filter.

Alternate method:-

Can we Fetch the values from dsa