Examination on low-frequency QTF of a platform
(0) For deep water offshore structures, the second order different frequency force may induce large responses in the horizontal directions. The second order different frequency force is usually computed by the Fourier transformation of the second order quadratic transform function (QTF), which is hard to be obtained due to its complexity, time consuming and the influence of ‘irregular frequency in its computation. In practical application Newmans approximation5 is widely used, without considering its viability. Based on a higher-order boundary element method, a numerical model is established for complex solution of second-order diffractions and radiations at different frequencies in bichromatic incident waves. The second-order quadratic transform functions are obtained by the integration of secondorder fluid pressure on the body surface. With application of Teng et als method9, full QTFs are computed for a typical TLP model ISSC. Computation shows that the second-order quadratic functions have distinct distribution at lower frequency ranges. Comparisons are made on the Newmans approximation with the full difference-frequency QTF.
low-frequency ISSC full QTF Newman’s approximation
Bin Teng Pei-wen Cong Ying Gou
State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China
国际会议
9th International Conference on Hydrodynamics(第九届国际水动力学会议 ICHD2010)
上海
英文
963-968
2010-10-11（万方平台首次上网日期，不代表论文的发表时间）