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http://dx.doi.org/10.12989/ose.2019.9.1.097

Irregular frequency effects in the calculations of the drift forces  

Liu, Yujie (Marine Dynamics Laboratory, Department of Ocean Engineering, Texas A&M University)
Falzarano, Jeffrey M. (Marine Dynamics Laboratory, Department of Ocean Engineering, Texas A&M University)
Publication Information
Ocean Systems Engineering / v.9, no.1, 2019 , pp. 97-109 More about this Journal
Abstract
Accurate calculation of the mean drift forces and moments is necessary when studying the higher order excitations on the floater in waves. When taking the time average of the second order forces and moments, the second order potential and motion diminish with only the first order terms remained. However, in the results of the first order forces or motions, the irregular frequency effects are often observed in higher frequencies, which will affect the accuracy of the calculation of the second order forces and moments. Therefore, we need to pay close attention to the irregular frequency effects in the mean drift forces. This paper will discuss about the irregular frequency effects in the calculations of the mean drift forces and validate our in-house program MDL Multi DYN using some examples which are known to have irregular frequency effects. Finally, we prove that it is necessary to remove the effects and demonstrate that the effectiveness of the formula and methods adopted in the development of our program.
Keywords
irregular frequency effect; drift force; hydrodynamics; body-wave interaction;
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Times Cited By KSCI : 3  (Citation Analysis)
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