Fluid flowmeter

• US 4,485,679 A
• Filed: 12/02/1982
• Issued: 12/04/1984
• Est. Priority Date: 12/10/1981
• Status: Expired due to Fees

• Current Assignee: IIT Industries Incorporated
• Original Assignee: ITT Industries (ITT, Inc.)
• Inventors: Batchelder, David N., Williamson, Roger J., Pitt, Gillies D., Prabakaran, Arulanandam M.
• Primary Examiner(s): Goldstein, Herbert
• Application Number:
  US06/446,158
• Time in Patent Office: 733 Days
• Field of Search: 73/861.22, 73/861.24
• US Class Current: 73/861.22
• CPC Class Codes: G01F 1/3218 bluff body design

Abstract

A vortex flowmeter having a double bluff body arrangement whereby vortices are generated at a rate corresponding to the fluid flow velocity. The upstream body and the downstream body together interact with the fluid stream to generate vortices. The arrangement introduces a relatively low blocking factor in comparison to simple bluff body arrangements. Vortex sensors are located between the bodies and downstream of the second body a distance between three and five times the diameter of that body.

Claims

1. A vortex flowmeter comprising:

a pipe section through which a fluid flow is directed;

first and second bodies disposed in the fluid path in said pipe section and in respective upstream and downstream positions;

means for detecting vortices generated by the interaction of the fluid flow with the combination of the two bodies, said vortices being generated at a rate proportional to the fluid flow rate;

means for translating said vortex frequency into a measure of the fluid flow rate, said first bluff body being tapered and pointing upstream, said second bluff body having a substantially flat surface normal to the flow;

vortex detecting means disposed between the first and second bodies; and

vortex detecting means disposed downstream of the second body by a distance between three and five times the diameter of that body.

2. A flowmeter as claimed in claim 1, wherein said first body is wedge shaped in cross-section and is disposed with the apex of the wedge directed in an upstream direction.

3. A flowmeter as claimed in claim 2, wherein said wedge has a half angle of 19°

to 20°

.

4. A flowmeter as claimed in claim 3, wherein said second body is T-shaped in cross-section and is disposed with the tail of the T directed in a downstream direction from the cross.

5. A flowmeter as claimed in claim 4, wherein the diameter of the second body is from 0.26 to 0.27 times the diameter of the pipe section.