Fluid flowmeter

• US 4,638,672 A
• Filed: 09/11/1984
• Issued: 01/27/1987
• Est. Priority Date: 09/11/1984
• Status: Expired due to Term

• Current Assignee: McCrometer, Inc. (Danaher Corporation)
• Original Assignee: Ametek Incorporated
• Inventors: McCall, Floyd
• Primary Examiner(s): WOODIEL, DONALD
• Application Number:
  US06/649,512
• Time in Patent Office: 868 Days
• Field of Search: 73/861.52, 73/861.22, 73/861.24, 73/861.63, 73/861.64, 73/861.61, 73/202, 138/44
• US Class Current: 73/861.52
• CPC Class Codes: B01F 25/3131 with additional mixing means other than injector mixers, e.g. screens, baffles or rotating elements
• CPC Class Codes: B01F 25/441 characterised by the configuration of the surfaces forming the slits
• CPC Class Codes: G01F 1/40 Details of construction of the flow constriction devices

Abstract

A fluid flowmeter is disclosed herein which includes a fluid displacement member positioned in the fluid flow to substantially linearize the velocity profile associated therewith. In one form of the invention the pressure differential in the fluid existing across the fluid displacement member is advantageously exploited, and several embodiments thereof are disclosed. In another form of the invention the fluid displacement member is utilized to produce trailing vortices.

Claims

1. Apparatus for measuring fluid flow through a conduit, comprising:

(a) A fluid flow displacement member mounted in said conduit and having sloped wall means for deflecting the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said slope wall means being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit;

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary flowpath having one end positioned upstream of said fluid displacement member and its opposite end positioned downstream of said region; and

(c) totalizer means in said auxiliary flowpath for determining the total fluid flow therethrough.

7. Apparatus as set forth in claims 1, 2, 3, 4, 5 or 6 wherein said displacement member is a disc in the form of frustums of two cones joined at their larger ends.

8. Apparatus as set forth in claims 1, 2, 3, 4, 5, 6, or 7 wherein said conduit means passes through the central axis of said fluid displacement member, providing an inlet in the upstream side thereof, and an outlet downstream of said region.

2. Apparatus for measuring fluid flow through a conduit comprising:

(a) a fluid displacement member mounted in said conduit and having sloped wall means for deflecting the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said sloped wall means being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates throughs said conduit;

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary flowpath having one end positioned upstream of said fluid displacement member and its opposite end positioned downstream of said regions; and

(c) rate-of-flow means in said auxiliary flowpath for determining the rate of fluid flow therethrough.

3. Apparatus for measuring fluid flow through a conduit, comprising a fluid displacement member mounted in said conduit to deflect the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said fluid displacement member being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit;

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary flowpath having one end positioned upstream of said fluid displacement member and its opposite end positioned downstream of said region;

(c) totalizer means in said auxiliary flowpath for determining the total fluid flow therethrough.

4. Apparatus for measuring fluid flow through a conduit comprising:

(a) a fluid displacement member mounted in said conduit to deflect the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said fluid displacement member being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit;

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary flowpath having one end positioned upstream of said displacement member and its opposite end positioned downstream of said region;

(c) rate-of-flow means in said auxiliary flowpath for determining the rate of fluid flow therethrough.

5. Apparatus for measuring fluid flow through a conduit comprising:

(a) a fluid flow displacement member mounted in said conduit and having sloped wall means for deflecting the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said sloped wall means being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit;

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary path having one end positioned upstream of said fluid displacement member and its opposite end positioned downsteam of said region; and

(c) transducer means, mounted across said auxiliary path for directly sensing and measuring the pressure differential between the said ends of said auxiliary path.

6. Apparatus for measuring fluid flow through a conduit, comprising:

(a) a fluid displacement member mounted in said conduit to deflect the fluid to flow through a region defined by the periphery of said displacement member and the interior surface portion of said conduit proximate said periphery, said fluid displacement member being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit; and

(b) conduit means extending transversely through said displacement member for diverting a portion of the fluid passing through said conduit along an auxiliary path having one end positioned upstream of said fluid displacement member and its opposite end positioned downstream of said region; and

(c) transducer means, mounted across said auxiliary path, for directly sensing and measuring the pressure differential between the said ends of said auxiliary path.

9. Apparatus for measuring fluid flow through a conduit, comprising:

(a) a fluid flow displacement member in the form of frustums of two cones joined at their larger ends for deflecting the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said fluid displacement member being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit; and

(b) conduit means passing through the central axis of said fluid displacement member and having one end in the upstream side thereof, and one end downstream of said region whereby fluid entering said conduit means is adapted to communicate with transducer means for directly sensing and measuring the pressure differential between the said ends.

10. Apparatus as set forth in claim 9 wherein the frustum positioned on the upstream side has a longer central axis than does the frustum positioned on the downstream side.

11. Apparatus for measuring fluid flow through a conduit, comprising:

(a) a fluid flow displacement member mounted in said conduit and having a sloped wall means for deflecting the fluid to flow through a region defined by the periphery of said fluid displacement member and the interior surface portion of said conduit proximate said periphery, said sloped wall means being effective to substantially linearize the velocity profile of said fluid in at least said region over a predetermined range of fluid flow rates through said conduit;

(b) conduit means through the central axis of said fluid displacement member, having one end in the upstream side thereof; and

(c) transducer means for directly sensing and measuring pressure differential between said upstream end and a point downstream of said region.