[Tlinxo]

I have simulated a progressive, small amplitude wave (wave length=6m,wave height=0.0304m, water depth=1m, calculating zone length=60m, and damping zone set at 48m) by Fluent VOF in k-wSST turbulent model. And I have transfer the waveform into Tecplot.

it looks a little decay , I'd like to know how can we determined the wave is "physically decay" or "artificially decay"? How can we know this decay is reasonable?

From now on I found out every value of amplitude at the wave crests and wave trough, and calculated the differences between them and the setting wave amplitude. And transfer the value into percentages.

But I can't decide how low is the difference, error of the percentage is physically decay for waves without artificial decay cause meshing or else.

[FMDenaro]

Originally Posted by Tlinxo

I have simulated a progressive, small amplitude wave (wave length=6m,wave height=0.0304m, water depth=1m, calculating zone length=60m, and damping zone set at 48m) by Fluent VOF in k-wSST turbulent model. And I have transfer the waveform into Tecplot.

it looks a little decay , I'd like to know how can we determined the wave is "physically decay" or "artificially decay"? How can we know this decay is reasonable?

From now on I found out every value of amplitude at the wave crests and wave trough, and calculated the differences between them and the setting wave amplitude. And transfer the value into percentages.

But I can't decide how low is the difference, error of the percentage is physically decay for waves without artificial decay cause meshing or else.

First of all, when you use a certain numerical scheme you have to be already aware if it introduces numerical diffusion or not.
Then, some specific test-case can be used to check if you work with a lot of numerical diffusion or not.
Finally, a grid refinement can help to check if the numerical diffusion tends to vanish. But you have also to know some characteristic of the flow problem you are studying, the equations will say you if you have a physical damping.