Bluff body flowmeter utilizing a moveable shutter ball responsive to vortex shedding

Claim 2

Apparatus for measuring the flowrate of fluid in a conduit comprising a vortex shedding body including a base surface facing fluid flow and a pair of converging surfaces extending downstream from said base surface, and having a pair of orifices each of which is adjacent to one of said converging surfaces; said body having an inner cylindrical chamber elongated in a plane parallel to said base surface and converging surfaces, said chamber having end portions at opposite ends of said chamber, and a pair of relatively smaller channels each of which extends from an individual one of said end portions of said chamber to an individual one of said orifices for communication with fluid flow in said conduit; a spherical shaped member situated in said chamber and moveable in a direction transverse to said fluid flow and along an axis of said body substantially parallel to said base surface and said converging surfaces in response to vortex induced changes at each said orifice; and means in nonfluid communication with said fluid flow in said conduit and responsive to the movement in said chamber of said member away from and toward said means for producing an electrical signal related to said flowrate.

Claim 3

The apparatus of claim 1 wherein said spherical shaped member has a diameter d, and said chamber has restraining end walls separated a distance of substantially 1.1d for limiting horizontal movement.

Claim 4

The apparatus of claim 1 wherein said vortex shedding body includes a cylindrical shaft running parallel to the long axis of said body with an opening at an end of said body, and a chamber body adapted to be removably inserted into said shaft and said cylindrical chamber being housed within said chamber body.

Claim 5

The apparatus of claim 3 wherein said smaller channels comprise a first pair of channel elements each extending between said cylindrical shaft and an individual one of the converging surface orifices, and said chamber body contains a second pair of channel elements communicating with said cylindrical chamber and in registry with said first pair of channels.

Claim 6

The apparatus of claim 3 wherein said chamber body contains a tool engaging surface at an end thereof facing said opening suitable for accessing said chamber body to remove it from said shedding body.

Claim 7

The apparatus of claim 5 wherein said vortex shedding body includes at least one support member at an end thereof for mounting said vortex shedding body in said conduit, and said cylindrical shaft extends into said support member.

Claim 8

The apparatus of claim 6 wherein said vortex shedding body includes a second support member for mounting said body in said conduit, said first pair of channel elements are positioned relatively closer to said second support member than to said one support member, and said second support member incorporates a channel for receiving said signal producing means.

Claim 9

The apparatus of claim 7 wherein said signal producing means includes a magnetic fielD generating means insertable into said support member from outside said conduit, and a pickup head projecting into said support member along a horizontal axis of said shedding body common to an axis of said cylindrical shaft for detecting EMF''s induced in said generated field by perturbations of said field by said spherical shaped member.

Claim 10

The apparatus of claim 1 wherein said spherical shaped member comprises a hollow nickel sphere.

Claim 11

Apparatus for measuring the flowrate of fluid in a pipeline comprising a bluff body having a base facing fluid flow effective to produce vortex shedding in said fluid, said surface extending along a diameter of said pipeline and between the walls thereof and having further a pair of planar converging surfaces extending downstream of said base surface forming a substantially triangular cross section of said bluff body, said bluff body having a cylindrical shaft parallel both to said base and said converging surfaces extending therethrough, said bluff body further having a first and second channel extending between respective ones of said converging surfaces and said cylindrical shaft, said first and second channels being offset from each other with respect to a longitudinal axis through said cylindrical shaft, a cylindrically shaped ball receiver having an outer diameter smaller than the inner diameter of said shaft suitable for insertion into said shaft, said bluff body having an opening to said shaft at one end only to receive said ball receiver, said receiver including a cylindrically shaped ball retaining chamber in which a spherical member is situated, said chamber being so positioned within said receiver and of proportions sufficient to allow movement of said member along said long axis, said receiver further including third and fourth channels extending from an outside surface thereof to opposite ends of said retaining chamber, and said third and fourth channels being offset from one another so to be in alignment with said first and second channels when said receiver is inserted into said shaft.

Claim 12

Apparatus for measuring the flowrate of fluid in a pipeline comprising a bluff body having a base facing fluid flow effective to produce vortex shedding in said fluid, said surface extending along a diameter of said pipeline and between the walls thereof and having further a pair of planar converging surfaces extending downstream of said base surface forming a substantially triangular cross section of said bluff body, said bluff body having a cylindrical shaft parallel both to said base and said converging surfaces extending therethrough, said bluff body further having a first and second channel extending between respective ones of said converging surfaces and said cylindrical shaft, said first and second channels being offset from each other with respect to a longitudinal axis through said cylindrical shaft, a cylindrically shaped ball receiver having an outer diameter smaller than the inner diameter of said shaft suitable for insertion into said shaft, said bluff body having an opening to said shaft at one end only to receive said ball receiver, said receiver including a cylindrically shaped ball retaining chamber in which a spherical member is situated, said chamber being so positioned within said receiver and of proportions sufficient to allow movement of said member along said long axis, said receiver further including third and fourth channels extending from an outside surface thereof to opposite ends of said retaining chamber, and said third and fourth channels being offset from one another so to be in alignment with said first and second channels when said receiver is inserted into said shaft.

Claim 13

The invention set forth in claim 10 wherein said bluff body includes a mounting member at one end thereof for securing said body to said pipeline, a magnetic field generating device being installed within said member for establishing a magnetic field about said retaining chamber, said spherical member being adapted to movement along said chamber axis in response to vortex shedding at a rate proportional to the fluid flowrate, and pickup means integrated with said generating device for detecting perturbations in said field as a result of the movement of said spherical member.

Claim 14

The invention set forth in claim 10 wherein said receiver incorporates a tool engaging surface which is accessible through said opening in said shaft to facilitate removal of said receiver from within said shaft.

Claim 15

The invention set forth in claim 10 wherein the distance along said one axis of said chamber in the direction of movement of said spherical member is equal approximately to 1.1 times the diameter of said spherical member.

Claim 16

Apparatus for measurement of the flowrate of fluid in a pipeline comprising a bluff body having a base facing fluid flow effective to produce vortex shedding in said fluid, said body being in registry with the inner walls of said pipeline and having a longitudinal axis coincident with a diametric axis of said pipeline, said body further including a pair of planar converging surfaces extending downstream of said base surface thereby defining a substantially triangular cross section of said bluff body, said bluff body having a substantially cylindrical shaftway along said longitudinal axis with an opening at one end of said body, said body further having a first and a second channel extending between respective ones of said converging surfaces and said shaftway, the central axis of said first and second channels being respectively perpendicular to a central axis of said shaftway and being offset from eaCh other with respect to said central axis a fixed distance, a ball receiver having a substantially cylindrically shaped outer surface and the diameter of said receiver is constant over its length and smaller than the inner diameter of said shaftway to permit insertion of said receiver therein, said receiver including a cylindrical ball retaining chamber having length 1.1m, a diameter m and a central longitudinal axis which is coincident with a central longitudinal axis of said retaining chamber, a spherical member having a diameter substantially equal to m situated within said retaining chamber and free to move along the central longitudinal axis thereof, said receiver further including third and fourth channels extending from an outside surface thereof to opposite ends of said retaining chamber along the circumferential inner walls thereof, said third and fourth channels being offset from one another and in axial alignment with said first and second channels when said receiver is installed within said shaftway, said receiver further incorporating a tool engaging surface on said outer surface which is adapted to be accessible through said shaftway opening to facilitate removal of said receiver, said bluff body including a mounting member at an end thereof for fastening said body through an opening in said pipeline, a magnetic field generating device being installed within said mounting member for establishing a magnetic field about said receiver, and said spherical member being adapted when oscillating in response to vortex shedding to cause perturbations in said field.

Claim 17

Apparatus for measurement of the flowrate of fluid in a pipeline comprising a bluff body having a base facing fluid flow effective to produce vortex shedding in said fluid, said body being in registry with the inner walls of said pipeline and having a longitudinal axis coincident with a diametric axis of said pipeline, said body further including a pair of planar converging surfaces extending downstream of said base surface thereby defining a substantially triangular cross section of said bluff body, said bluff body having a substantially cylindrical shaftway along said longitudinal axis with an opening at one end of said body, said body further having a first and a second channel extending between respective ones of said converging surfaces and said shaftway, the central axis of said first and second channels being respectively perpendicular to a central axis of said shaftway and being offset from eaCh other with respect to said central axis a fixed distance, a ball receiver having a substantially cylindrically shaped outer surface and the diameter of said receiver is constant over its length and smaller than the inner diameter of said shaftway to permit insertion of said receiver therein, said receiver including a cylindrical ball retaining chamber having length 1.1m, a diameter m and a central longitudinal axis which is coincident with a central longitudinal axis of said retaining chamber, a spherical member having a diameter substantially equal to m situated within said retaining chamber and free to move along the central longitudinal axis thereof, said receiver further including third and fourth channels extending from an outside surface thereof to opposite ends of said retaining chamber along the circumferential inner walls thereof, said third and fourth channels being offset from one another and in axial alignment with said first and second channels when said receiver is installed within said shaftway, said receiver further incorporating a tool engaging surface on said outer surface which is adapted to be accessible through said shaftway opening to facilitate removal of said receiver, said bluff body including a mounting member at an end thereof for fastening said body through an opening in said pipeline, a magnetic field generating device being installed within said mounting member for establishing a magnetic field about said receiver, and said spherical member being adapted when oscillating in response to vortex shedding to cause perturbations in said field.