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Regarding: Choosing the Right X 41 Value for floating body simulations in REEF3D

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Old   August 23, 2023, 10:09
Default Regarding: Choosing the Right X 41 Value for floating body simulations in REEF3D
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Bhargav
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I'm working with REEF3D and I'm a bit confused about the X 41 parameter. The default value is 0.6, but in the ctrl.txt for heave decay of a sphere given in tutorial (user REEF3D guide), you used 2.1.

I tried both values for a cylinder's heave decay in a 2D wave tank, and the results are different. Any suggestions on which value I should use?

Thanks you
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Old   August 24, 2023, 06:15
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Please use 0.6. The old value was 2.1 for the old version of the direct forcing algorithm.
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Old   August 24, 2023, 06:16
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Will be updated in the upcoming release.
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Old   August 25, 2023, 10:32
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I've been continuously working on a heave decay simulation of a float using REEF3D, incorporating the valuable suggestions provided by the REEF3D team. The simulation setup closely follows the methodology outlined in the paper titled "Wendt, Fabian, Kim Nielsen, Yi-Hsiang Yu, Harry Bingham, Claes Eskilsson, Morten Kramer, Aurélien Babarit, Tim Bunnik, Ronan Costello, Sarah Crowley, and et al. 2019. 'Ocean Energy Systems Wave Energy Modelling Task: Modelling, Verification and Validation of Wave Energy Converters' (Journal of Marine Science and Engineering 7, no. 11: 379. https://doi.org/10.3390/jmse7110379)."

Initially, I achieved promising agreement between the results. However, as the simulation progresses over time, I've observed a growing deviation between these two sets of results. To gain a better understanding, I performed a comparison using different values of X41, 2.1 in one case and 0.6 in another. The plotted data clearly indicates that X41 = 2.1 provides a better match than X41 = 0.6.

For your convenience, I've attached the pertinent control, ctrl, and solid files that were utilized in the simulation. Additionally, I've included a comparative plot that highlights the observed differences. Your expert insights are invaluable, and if any discrepancies or potential errors are identified in my input files, please provide your guidance in addressing them.

Thank you for your time and assistance.
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Attached Files
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File Type: txt ctrl.txt (429 Bytes, 11 views)
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