Simulation Settings

[hhh850]

Dear

I am conducting a simulation using FAST.Farm with the IEA 15MW reference wind turbine to replicate the wind farm configuration described in the paper https://doi.org/10.5194/wes-2024-6. The TurbSim-generated wind field aligns well with the paper’s specifications.

Specifically, I selected Case 1 from Figure 11 of the paper, where five turbines are spaced 7.7D apart with a 0° wind direction and 0° yaw angles for all turbines.

The simulation ran for 2400 seconds, and the normalized average power over the last 1800 seconds was analyzed. However, the results deviate from the trends reported in the paper: the third turbine’s power output is expected to be the highest, followed by a slight decrease in downstream turbines, but my simulation shows an inconsistent pattern (e.g., the third turbine does not exhibit the maximum power).

I suspect potential issues with the degree-of-freedom (DOF) settings in the ElastoDyn (ED) file or other configuration parameters. The paper explicitly uses the fixed-bottom IEA 15MW reference turbine, and I have attached my key parameter settings and configuration files for review. Any insights into resolving this discrepancy would be greatly appreciated.

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IEA-15-240-RWT-Monopile-5-4.zip

[jjonkman]

Dear @hhh850,

I haven't reviewed your zip attachment yet, but I would first check k_VortexDecay, where you have used the DEFAULT value of 0.0001, whereas the paper you reference uses 0.0.

Best regards,

[hhh850]

dear @jjonkman
Thank you for your reply. Previously, I overlooked the influence of the parameter k_VortexDecay. After modifying this parameter, I obtained good agreement with the reference results for Case 1.

I then extended the comparison to two additional operating conditions. Overall, the results are much closer to those presented in the paper; however, noticeable discrepancies still remain in some areas. For example, there is a significant deviation in the average power output of WT1 under Operating Case 2.

From your professional perspective, do you consider these differences to be within a reasonable range?

[jjonkman]

Dear @hhh850,

Overall, the trends in your plots are similar to those from the paper. It could be that the use of different random seeds in the turbulent inflow generation would change the results.

Best regards,

[hhh850]

Dear @jjonkman
Thank you very much for your detailed explanation.Your insights have been extremely helpful and clarified the issue I was struggling with.I truly appreciate the time and effort you took to assist me.
Thanks again for your generous support.

Best regards,