... upstream oil & gas pore water pressure geomaterial excess pore water pressure ratio water pressure monopile foundation instability shear stress rubble mound cylindrical structure wave loading sediment countermeasure excess pore water pressure movable bed surface shape...

... instability ABSTRACT The objective of the current work is to study numerically the influence of large variations of Weber and Reynolds numbers on the global wave shape of a Single Impact Wave (SIW, wave generated from initial condition at rest and leading to an impact on a wall) just before impact...

... a significant impact on the open water performance, vortex structures, as well as the instability of the wake evolution. In this paper, based on the Ka4-70 propeller and 19A duct model, simulations of open water propeller and a ducted propeller with tip clearance d = 1.01mm are carried out. Firstly, open...

... consisting of two alternating phases: an approximately flutter motion and a vibration similar to noise with a small amplitude. INTRODUCTION The cantilevered pipe is a novel and most challenging device in the floating structure for deep-sea mining. The internal flow causes the instability...

... and continental structures (MacKinnon et al, 2017). In terms of nonlinear wave-wave interactions, parametric subharmonic instability (PSI) is considered as one possible dissipation mechanism of the internal waves. The energy will flow from the primary wave to a pair of subharmonic waves of half the frequency...

... Abstract The parametric resonance, which could induce severe consequence like fatigue, and further lead to oil-spill risk, has been vastly discussed in about the offshore pipelines. In this paper, a top-tensioned riser has been modelled, and the parametric instability of such structure has...

... ABSTRACT To research the phenomenon of heading instability of FPSO, the model test in a scale ratio 1:80 was carried out. It was observed that heading of the model drifted significantly in regular waves. For studying the motion in transitional and stabilized zones, simulation in SESAM...

... breaking induced by dispersive focusing waves and modulational instability. By comparison with some existing experiments, the ability of the present model to predict breaking-onset and breaking energy dissipation are verified. Additionally, the wavelet transform is applied to examine the variations of wave...

... equation gravity center limit curve equation instability coefficient amplitude motion happen Research of Porpoising Phenomenon of M-hull Planing Craft Xiaofei Mao1, 2, Zeshuang Yu2, Liang Yan2 1Key Laboratory of High Performance Ship Technology of Ministry of Education 2School of Transportation...

... ABSTRACT Sloshing model tests or wave impact tests in flumes show large variability of local impact pressure measurements. One of the reasons of such variability is the generation of free surface instabilities by the shearing gas flow at the free surface just before the impacts (Kelvin...

... of the pipe cross section. The torque can be generated by, for example route curves, or the weight of inline structures. The rotation phenomenon may be characterised as an instability, as in the case of top-heavy structures which only generate a torque when their centre of gravity becomes laterally displaced...

... wake transition vortex spatiotemporal symmetry three-dimensional reconstruction equation configuration wake control splitter plate instability cylinder wavelength reynolds number fluid mechanics circular cylinder stability analysis neutral stability curve transition mechanics...

... ABSTRACT Modulation instability describes the exponential amplification of a weak perturbation on top of a plane wave background and it has been extensively studied in the context of weakly nonlinear evolution equations such as the nonlinear Schrödinger equation (NLSE). It has been further...

.... The influence of the nonlinear visco-elastic rheology of ice and the eddy viscosity in the ice-adjacent water layer on wave damping and modulation instability are investigated and discussed in this paper. Introduction Surface waves can propagate below drift ice and create ice failure over large distances...

..., placing the embankment over the mound by using rubble materials or filter units was confirmed effective against breakwater instability. KEY WORDS: Centrifuge Model Test; Tsunami Overflow; Composite Breakwater; Seepage; Scour; Embankment. INTRODUCTION In the 2011 off the Pacific Coast of Tohoku Earthquake...

... liquefaction. It is found that liquefaction may, for some instances, trigger instability of rubble-mound breakwater through the seabed under regular waves. Introduction Marine infrastructure plays a vital role in relation to energy, environment and sustainable development. Coastal and offshore structures...

... lindgren evolution orbital amplitude spectrum wave interaction nouguier frequency fluid mechanics benjamin-feir instability instability gravity wave equation amplitude spectral amplitude second-order lagrangian interaction expansion interaction eulerian expansion particle...

... Abstract The influence of damage in the anti-birdcaging tape and plastic sheath on radial instability is examined through continuum finite element analysis. The numerical procedures are calibrated with physical tests on a flexible pipe subject to pure axial compression. An implicit solver...

... probability were investigated. The results showed that both modulation instability and linear directional focusing can generated the freak wave in multi-directional wave train. The directionality spreading had significant effects on freak wave occurrence probability. In relatively deep water, the waves...

... wavelength of 0.73L (Thiagarajan et al. 2013). In the present study, the authors aimed to look into the problem theoretically to analyse the heading instability. In this paper, the Cox equations for the mean drift force and moment are applied to find the approximate yaw motion of the system. For treating...