|
[Sponsors] |
![]() |
![]() |
#1 |
New Member
Join Date: Jan 2025
Posts: 3
Rep Power: 2 ![]() |
Hi,
I would like to rerun a numerical simulation with an irregular sea. Is there a way to generate the same sea state more than once? For instance by using the output waves from a simulation as input to another simulation. |
|
![]() |
![]() |
![]() |
![]() |
#2 |
Member
Alexander Hanke
Join Date: Dec 2023
Location: Trondheim
Posts: 52
Rep Power: 4 ![]() |
Hi.
That should be possible using for example the hydrodynamic coupling, using the state file system and initializing the later simulations with your first one or using sea state data (B85, B92=50). Using sea state data is probably the saves as it will retain all relevant information. Coupling and state files might not retain all relevant information. |
|
![]() |
![]() |
![]() |
![]() |
#3 |
New Member
Join Date: Jan 2025
Posts: 3
Rep Power: 2 ![]() |
Thank you for answering.
I guess when using the same module twice hydrodynamic coupling is not an option. By the B 85 parameter, do you mean to use the spectrum generated in the Log-Wave folder as input to a later simulation? And what do you mean when you refer to the B 92 50 parameter, are you referring to the wave reconstruction method from this article: Aggarwal A., Pakozdi C., Bihs H., Berthelsen P.A., Myrhaug D., Alagan Chella M. (2018) Free Surface Reconstruction For Phase Accurate Irregular Wave Generation, Journal of Marine Science and Engineering, Vol. 6, Issue 3, Nr. 105 Again, thank you for helping me ![]() Last edited by vix3; January 14, 2025 at 04:09. |
|
![]() |
![]() |
![]() |
![]() |
#4 | ||
Member
Alexander Hanke
Join Date: Dec 2023
Location: Trondheim
Posts: 52
Rep Power: 4 ![]() |
Quote:
He also found a seed value B139 for the irregular waves. Quote:
|
|||
![]() |
![]() |
![]() |
![]() |
#5 |
Super Moderator
Widar W Wang
Join Date: Mar 2016
Location: Norway
Posts: 19
Rep Power: 11 ![]() |
Hi,
The wave reconstruction paper you mentioned is correct. Generally, there are two ways to reproduce the exact time series for irregular waves: 1) using a wavemaker signal (if available from an experiment) or 2) wave reconstruction (giving amplitude, frequency and phase for each component in an irregular wave train) If one does not have any of these, one can take the irregular wave time series, make an FFT, extract the wave components information, and then use that for wave reconstruction. Hope this helps. |
|
![]() |
![]() |
![]() |
![]() |
#6 |
New Member
Join Date: Jan 2025
Posts: 3
Rep Power: 2 ![]() |
Great, thank you!
I have been testing this method by generating waves using FNPF and using the wave component file from that run as input for another run in the CFD module. It looks like the two runs are producing the same waves ![]() |
|
![]() |
![]() |
![]() |
Tags |
cfd, fnpf, irregular waves, reconstruction |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Time-step size for coupled implicit simulations | pi120 | STAR-CCM+ | 3 | March 16, 2022 22:08 |
Water-Air simulations | Miguel Hernandez | OpenFOAM Running, Solving & CFD | 26 | September 18, 2021 06:38 |
Ways to get rid of negative pressure in numerical simulations | arungovindneelan | Main CFD Forum | 7 | July 28, 2017 05:05 |
Numerical viscosity due to the MUSCL and HLL coulpled scheme | sonsiest | Main CFD Forum | 0 | May 23, 2011 16:37 |
New Books and Numerical Software | Eleuterio TORO | Main CFD Forum | 0 | December 18, 1998 13:41 |