An underwater pipeline capable of suppressing vortex-induced vibration

Abstract

The invention discloses a submarine pipeline capable of restraining vortex-induced vibration. The submarine pipeline is formed in the mode that the cross section of the lower end of a pipeline body is pulled upwards in a spiral mode through the center axis in the axial direction, the outer boundary of the cross section of the lower end is formed by end-to-end connection of six 60-degree arcs in the tangential direction, the six 60-degree arcs are the arc a, the arc b, the arc c, the arc d, the arc e and the arc f in sequence in the clockwise rotation direction, the line connecting the circle center O1 of the arc a with the central point O of the lower cross section, the line connecting the circle center O2 of the arc c with the central point O of the lower cross section, and the line connecting the circle center O3 of the arc e with the central point O of the lower cross section are in the same length, and the included angles between the three lines are 120 degrees; a circle with a radius of R=O1O2+O1A is made to be tangent to the circle O2 and the circle O3, O1A is the radius of the arc a, the arc between tangent points is the arc d, and O2 serves as the circle center; a circle with a radius R is made to be tangent to the circle O1 and the circle O3, and the arc between tangent points is the arc f; a circle with a radius R and O3 serving as the circle center is made to be tangent to the circle O1 and the circle O2, and the arc between tangent points is the arc b. The submarine pipeline capable of restraining vortex-induced vibration is insensitive to incoming flow direction and excellent in flow-resistant strength and vibration restraining performance.

Description

technical field [0001] The invention belongs to the technical field of laying underwater facilities, and in particular relates to a pipeline capable of suppressing underwater vortex-induced vibration. Background technique [0002] There are many slender pipes (or pipelines) structures in marine oil production, exploration and other systems, which are used to fix platforms and transport fuel oil, etc., and are indispensable structures for offshore engineering ships or offshore platform operations. The cross-sectional shape of these pipelines is mostly circular, such as oil production risers and natural gas pipelines, etc. These pipelines have been submerged in seawater for a long time and are subjected to the action of water flow, and the water flow produces eddies due to uneven pressure distribution during the flow process. The formation and shedding of the vortex induces the phenomenon of vortex-induced vibration in the pipeline. When the vortex shedding frequency is close...

AI Technical Summary

Problems solved by technology

But in actual use, the cost is very high, and the operation is not easy to implement

Passive suppression means that no external power energy and real-time control are required, but an auxiliary spoiler device is added to control the vortex generation method and destroy the vortex development process. Commonly used devices include fairings, partition plates, spiral side plates, and axial slats , control rods, etc., but the cost is increased and additional installation is difficult. Among them, the spiral side plate is used as a protrusion suppression device on the surface of the cylinder, which disturbs the wake field of the vortex by separating the shear layer or separation line, and because of its isotropy , can adapt to the complex and changeable marine environment

However, due to the existence of the spiral side plate, the front flow area of ​​the riser is increased, resulting in an increase in the resistance along the flow direction

In addition, its installation and control requirements are relatively high

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