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QTF

Hello, Professor David, I want to know how to set it in the platform file to calculate the sum-frequency loads on all potential flow bodies  using the full QTF method instead of the Newman approximation method.Is it right to just turn on ‘USE_ DIFF_ FREQS’ and ‘USE_ MEANDRIFT’ is enough?

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My statement above is wrong: calculate the difference-frequency loads on All potential flow bodies instead of the sum frequency

Hi Sun,

if you want to explicitly calculate the full QTF you need to set USE_DIFF_FREQS to “true” and both USE_NEWMAN and USE_MEANDRIFT to “false”.

  • If USE_MEANDRIFT is “true” only the mean difference forces are calculated, regardless of the settings of the other two variables.
  • If USE_NEWMAN is “true” and USE_MEANDRIFT is “false” the Newman approximation is used, regardless of the setting of USE_DIFF_FREQS.
  • If USE_DIFF_FREQS is “true” the full QTF is only calculated if both USE_NEWMAN and USE_MEANDRIFT  are set to false.

If you have multiple potential flow bodies then you need to assign a POT_DIFF_FILE to each of those bodies. Use POT_DIFF_FILE_2 for the 2nd body, POT_DIFF_FILE_3 for the 3rd and so on…

Best,

David

 

Thank you, Professor David

A simulation of the Lillgrund windfram in QBlade, using the Dynamic Wake Meandering Model