The wave forces on pipes near the ocean bottom are studied with model test in this paper. Comparisons of four different methods show that the uncommonly used method - Least Square Mass (LSM) is the most stable one. Th...The wave forces on pipes near the ocean bottom are studied with model test in this paper. Comparisons of four different methods show that the uncommonly used method - Least Square Mass (LSM) is the most stable one. The in-line and transverse forces on the pipe, which is placed at various distances from the bottom of the wave tank, are measured. The force transfer coefficients (CD, CM, CL) are much larger when the pipe is near the bottom than when it is free. But the coefficients do not increase unlimitedly: they reach their maxima at ζ (gap ratio = e / D) = 0.1 (gap ratio ζ = e / D). An interesting result is that the ratio of lift force frequency (f′L) to wave frequency (fw) is 2.0. In the paper, the curves of coefficients are given.展开更多
文摘The wave forces on pipes near the ocean bottom are studied with model test in this paper. Comparisons of four different methods show that the uncommonly used method - Least Square Mass (LSM) is the most stable one. The in-line and transverse forces on the pipe, which is placed at various distances from the bottom of the wave tank, are measured. The force transfer coefficients (CD, CM, CL) are much larger when the pipe is near the bottom than when it is free. But the coefficients do not increase unlimitedly: they reach their maxima at ζ (gap ratio = e / D) = 0.1 (gap ratio ζ = e / D). An interesting result is that the ratio of lift force frequency (f′L) to wave frequency (fw) is 2.0. In the paper, the curves of coefficients are given.
