Interpolation points of pointsheight.txt in Measuretool

mzbr1g12

Hi,

I am quite new to DualSphysics. I tried the casewavemaker to compare to my coding as I am now working on generating propagating wave using paddle motion. From the example, I noticed that the positions where the interpolation is performed for capturing wave elevation/wave height are given in the text file pointHeight.txt. I plotted the data from the excel file (pointsHeight.docx) and compared the free surface predictions with my c++ results. However, it seems that the interpolation data quite flat on the wave crest and trough and do not show a good representation of free surface elevation.

The wave elevation seems good in the simulation but when it comes to using measuretool.exe, the interpolation quite bad. So its difficult to get a good pressure and velocity under the wave crest and wave trough.

Anyone can help me to refine the interpolation process so that I can get much smoother free surface representation. I have tried changing the points list of z-axis from 140 to 200 and not much difference I can say.

Thank you.

Alex

StepsZ is the parameter that will give you better accuracy.
Try to define as much as points as possible in Z position.

Regards

mzbr1g12

Thank you.. the default stepZ in the textfile is 0.01. I tried 0.005 but somehow its not working. Does the code have limitation on this stepz value?? I cant really look on how Measuretool works as it is not provided as opensource code.

Alex

In Points.txt you can define the following parameters:

"POINTSLIST"
BeginX BeginY BeginZ
StepX StepY StepZ
CountX CountY CountZ

So that you are creating points to "measure" values at the positions from BeginZ till StepZ*CountZ separated StepZ. In all these points a value of mass is computed, when this value of mass becomes the half of the reference mass, that Z position is assumed to be the free-surface position. Thus as much points you have in Z, more accurate will be.

Regards

Alex

mzbr1g12

Thank you.

One more thing. I have noticed there is no command in the xml files/parameters on changing the use of riemann solver, from none to conservative or to non conservative option. Does this mean Riemann solver already included in the coding ?

Alex

Read the guide