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Reply To: Avoiding spurious peak in residual convergence plot

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#4906
sthavishtha
Participant

Dear Dr. Mathias

Thanks for your fast reply.

I was actually referring to the peak in the residual convergence plot at around 100,000 time steps (plot of residual error vs number of time steps) at the link. I compute the residual error as energy1 - energy0)/energy1 where energy1 and energy0 are sLattice.getStatistics().getAverageEnergy() computed at the current time step and previous time step respectively.

Though sudden peaks and troughs are possible in such residual convergence plots, the reason I call this as a “Spurious peak” is because I notice a typical change in the flow structure at a time instant around this peak only at high Reynolds numbers. This was not noticed at low Reynolds numbers.

Regards
Sthavishtha