Strakes

Abstract

An improved strake for structures that are subject to vortex induced vibrations and motions due to fluid flow around the structure. One embodiment includes a streamliner on the edge of the strake. The streamliner may be added to existing strakes or may be formed at the same time as the strake for extruded strakes. The streamliner reduces vortex induced vibrations and motions of the structure to which the strake is attached. Another embodiment of the invention provides a tension resisting support attached to the strake and structure. The support provides a different load path along the strake than the previously known art for carrying the pressure loading from fluid pressure acting normal to the surface of the strake.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, forming a part of this specification, and in which reference numerals shown in the drawings designate like or corresponding parts throughout the same:

FIG. 1 illustrates a prior art strake arrangement with three starts.

FIG. 2 illustrates a prior art strake arrangement with four starts.

FIG. 3 is a sectional view of a prior art strake.

FIG. 4 is a sectional view of a prior art strake.

FIG. 5 is a sectional view of a prior art strake.

FIG. 6 is a sectional view of the invention.

FIG. 7 is a sectional view of another embodiment of the invention.

FIG. 8 is a view taken along lines 8-8 in FIG. 1 and illustrates another embodiment of the invention.

Claims

1. On a structure subject to fluid flow that results in vortex induced vibrations or motions and having at least one strake that extends radially from the structure, an improved strake, said improved strake comprising a streamliner attached to the end of the strake distant from the structure.

2. The improved strake of claim 1, wherein said streamliner is attached along the full length of the strake.

3. The improved strake of claim 1, wherein said streamliner is attached along a portion of the length of the strake.

4. The improved strake of claim 1, wherein said streamliner comprises an enlarged tip.

5. The improved strake of claim 4, wherein said enlarged tip is of a circular shape.

6. The improved strake of claim 4, wherein said enlarged tip is of a tear drop shape.

7. On a structure that has at least one strake that extends radially from the structure, an improved strake, said improved strake comprising an enlarged circular tip.

8. The improved strake of claim 7, wherein said enlarged circular tip extends along the full length of the strake.

9. The improved strake of claim 7, wherein said enlarged circular tip extends along a portion of the length of the strake.

10. On a structure that has at least one strake that extends radially from the structure, an improved strake, said improved strake comprising an enlarged tear drop shaped tip.

11. The improved strake of claim 10, wherein said enlarged tear drop shaped tip extends along the full length of the strake.

12. The improved strake of claim 10, wherein said enlarged tear drop shaped tip extends along a portion of the length of the strake.

13. On a structure that has at least one strake that extends radially from the structure, a tension resisting support comprising a rigid block attached to the structure and the strake at each end of the strake.