Testing device for simulating bidirectional self-induced vibration of deep-sea stand columns under inclined uniform flow

Abstract

The invention discloses a testing device for simulating bidirectional self-induced vibration of deep-sea stand columns under inclined uniform flow. The testing device obtains velocity and stress of a cylinder body through measuring, obtains actual motion response signals under the effect of water flow by solving a motion equation of the cylinder body and exerts the actual motion signals onto models through a servo motor to enable the models to move, so that self-oscillation motion is simulated. During test, a horizontally sliding module is used for simulating flow and vortex-induced oscillation in the horizontal direction, and a vertically sliding module is used for simulating vortex-induced vibration in the vertical direction. The device sets parameters to simulate model structure performance, avoids messy testing operations in a traditional self-oscillation device, accelerates testing progress, provides large freedom degree for selection of parameters of a vibration system, simulates vortex-induced vibration bidirectionally and synchronously, simulates special working conditions of inclined flow, adopts large-scale stand column subsection to reduce scale effect, and adopts an end prosthesis device to solve the problem of model boundary effect.

Description

technical field [0001] The invention relates to the field of marine engineering, in particular to a test device for simulating bidirectional self-excited vibration of a deep-sea riser that flows obliquely and uniformly. Background technique [0002] The riser in the actual marine environment is a slender and flexible structure, which will generate vortex-induced vibration under the action of ocean currents. The structural fatigue or possible resonance caused by the vibration will pose a great threat to the safety of marine structures. [0003] The vortex-induced vibration is self-excited for the riser in the ocean. Due to the limitation of real-scale test conditions, the vortex-induced vibration phenomenon of flexible risers is mainly studied through model tests and numerical simulations. The model test divides the flexible riser into multiple sections, assuming that each section is a rigid cylinder, and performs a forced oscillation test or a self-excited oscillation test ...

AI Technical Summary

Problems solved by technology

[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides a test device for simulating the two-way self-excited vibration of a deep-sea riser with oblique uniform flow. Numerical simulation of the motion characteristics of the riser with virtual structural parameters solves the problem that the existing test device is limited to the actual structural performance of the model, and can only carry out forced vibration with a predetermined period, which is limited to the simulation of downstream single-degree-of-freedom vibration, and the scale effect is large. In short, it is impossible to more realistically simulate the movement of the riser in the actual sea state

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