Bionic fish-shaped ocean riser streaming control and vibration suppression device and method

Abstract

The invention relates to a bionic fish-shaped ocean riser streaming control and vibration suppression device and method. The device is composed of two steering bearings, a fish-shaped fairing and a rotating five-impeller. The fish-shaped fairing is of an integrally-formed spun-cone-shaped streamline structure and is arranged outside an ocean riser in a sleeving mode, so that a streaming boundary layer separation point is migrated backwards, and formation of vortexes is delayed. A flat plate is separated at the tail of the fish-shaped fairing to divide a flowing space, interference of shear layers on the two sides is avoided, and the attack angle is adjusted through rotation under ocean current impact. In addition, under the synergistic effect of sieve mesh fin circular flow guide hole drainage, fishbone-shaped through hole fluid allocation, rotating of the rotating five-impeller and conical fish mouth jet flow, development of the ocean riser streaming boundary layer and the shear layers is interfered, the boundary layer separation point is changed, the three-dimensional structure of wake flow vortexes and a flow field around a front stagnation point are damaged, formation and development of the vortexes are suppressed, the flowing resistance and lift force are reduced, and vortex-induced vibration suppression without energy consumption is achieved.

Description

technical field [0001] The invention belongs to the technical field of vortex-induced vibration suppression of marine risers, and in particular relates to a bionic fish-shaped marine riser flow control and vibration suppression device and method. Background technique [0002] In the process of developing marine energy, marine risers, risers, submarine pipelines, mooring chains, jumpers, suspension pipes, offshore platform pillars, drilling derricks and other equipment are affected to varying degrees by ocean winds, waves, currents, etc. vortex-induced vibration hazards. [0003] In order to suppress the vortex-induced vibration of blunt structures, scholars have designed many suppression devices in recent years. According to whether the devices need to consume extra energy, they can be divided into two categories: active control and passive control. Among them, active control needs to consume external energy, including suppression methods such as air jets and rotating contr...

AI Technical Summary

Problems solved by technology

Although there are passive suppression devices such as separation disks, fairings, and spiral strakes, they all have significant shortcomings. The separation disks and fairings are very sensitive to the angle of attack of the incoming flow, and the spiral strakes will increase the drag force of the structure.

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