Closely coupled, dual turbine volumetric flow meter

Claim 2

A meter for measuring a volumetric flow of a fluid in a conduit, which comprises: a pair of independent turbine assemblies, each of said turbine assemblies having a plurality of rotor blades and each adapted to have a speed of rotation representative of the volumetric fluid flow; a flow randomizer located between said pair of turbine assemblies, said randomizer having at least a vane, said randomizer spaced from said rotor blades of one turbine assembly by a distance equal to between approximately 5 and approximately 10 times a thickness of said randomizer vane, and being operable to eliminate substantially all flow effects of one of said turbine assemblies upon said other turbine assembly; and a transducer for detecting said speed of rotation of at least one of said turbine assemblies.

Claim 3

The flow meter of claim 1, wherein said flow randomizer comprises a plurality of vanes emanating radially from a central diffuser.

Claim 4

The flow meter of claim 1, wherein said flow randomizer comprises a combination of concentric rings and a plurality of vanes.

Claim 5

The flow meter of claim 1, wherein a length of said flow meter is less than or equal to 3 times the nominal diameter of said conduit transporting said fluid.

Claim 6

The flow meter of claim 1, wherein said turbine assemblies are each cantilever turbine assemblies.

Claim 7

The flow meter of claim 1, wherein said transducer means is a magnetic inductance turbine pickup.

Claim 8

The flow meter of claim 6, further comprising two magnetic inductance turbine pickups for each turbine assembly electrically separated by about 90°.

Claim 9

The flow meter of claim 2, wherein said flow randomizer vanes have a thickness, t, that satisfies the relationship: L v /60≦t≦L v /20, where L v is the average length of said randomizer vanes.

Claim 10

The flow meter of claim 2, wherein said flow randomizer vanes have a height, h, that satisfies the relationship: 0.20d m ≦h≦0.275d m , where d m is the inside diameter of said flow meter.

Claim 11

The flow meter of claim 1, wherein said flow randomizer further comprises a plurality of vanes, and wherein said flow randomizer is spaced from a plane formed by leading edges of one of said turbine assemblies a distance substantially equal to a distance at which a flow shear layer produced by any one of said plurality of vanes converges.

Claim 12

The flow meter of claim 2, wherein said flow randomizer vanes have a length, L v , that satisfies the relationship: L v ≧d m /2, where d m is the nominal inside diameter of said flow meter.

Claim 13

A volumetric fluid flow meter for measuring flow in a conduit, which comprises: a first bi-directional, substantially non-magnetic, independent turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second bi-directional, substantially non-magnetic, independent turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first bi-directional turbine assembly and said second bi-directional turbine assembly, said randomizer having a plurality of vanes of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the speed of rotation of said first turbine; a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine; and wherein an overall length of said flow meter is equal to or less than 3 times an inside diameter of said flow meter.

Claim 14

A volumetric fluid flow meter for measuring flow in a conduit, which comprises: a first bi-directional, substantially non-magnetic, independent turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second bi-directional, substantially non-magnetic, independent turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first bi-directional turbine assembly and said second bi-directional turbine assembly, said randomizer having a plurality of vanes of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the speed of rotation of said first turbine; a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine; and wherein an overall length of said flow meter is equal to or less than 3 times an inside diameter of said flow meter.

Claim 15

The flow meter of claim 12, wherein said flow randomizer comprises a plurality of vanes emanating radially from a central diffuser.

Claim 16

A volumetric fluid flow meter which comprises: a first independent cantilevered turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second independent cantilevered turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first turbine assembly and said second turbine assembly, said randomizer having a plurality of vanes of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the Speed of rotation of said first turbine; and a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine; and wherein an overall length of said flow meter is equal to or less than 3 times an inside diameter of said flow meter.

Claim 17

A volumetric fluid flow meter which comprises: a first independent cantilevered turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second independent cantilevered turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of rotors, said turbine adapted to freely rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first turbine assembly and said second turbine assembly, said randomizer having a plurality of vanes of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the Speed of rotation of said first turbine; and a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine; and wherein an overall length of said flow meter is equal to or less than 3 times an inside diameter of said flow meter.

Claim 18

The flow meter of claim 13, wherein said flow randomizer vanes have a thickness, t, that satisfies the relationship: L v /60 ≦t≦L v /20, where L v is the average length of said randomizer vanes.

Claim 19

The flow meter of claim 13, wherein said flow randomizer vanes have a thickness, t, that satisfies the relationship: L v /40≦t≦L v /25, where L v , is the average length of said randomizer vanes.

Claim 20

The flow meter of claim 13, wherein said flow randomizer vanes have a height that is approximately one-half of a diameter of said central diffuser.

Claim 21

The flow meter of claim 13, wherein said flow randomizer vanes have a height, h, that satisfies the relationship: 0.20d m ≦h≦0.275d m , where d m is the nominal inside diameter of said flow meter.

Claim 22

The flow meter of claim 14, wherein said flow randomizer is spaced from a plane formed by leading edges of one of said turbine assemblies by a distance of between approximately 5 and approximately 10 times an average randomizer vane thickness.

Claim 23

The flow meter of claim 12, wherein said flow randomizer is spaced from a plane formed by leading edges of one of said turbine a distance at which a flow shear layer produced by any one of said plurality of vanes converges for a predetermined fluid flow.

Claim 24

The flow meter of claim 14, wherein said flow randomizer is spaced from a plane formed by leading edges of one of said turbine assemblies a distance of about 6 to 8 times an average randomizer vane thickness.

Claim 25

The flow meter of claim 13, wherein said flow randomizer vanes have a length, L v , that satisfies the relationship: L v ≧d m /2, where d m is the nominal inside diameter of said flow meter.

Claim 26

The flow meter of claim 13, wherein said flow randomizer vanes have a length, L v , that satisfies the relationship: 3d m /4≦L v ≦d m , where d m is the nominal inside diameter of said flow meter.

Claim 29

The flow meter of claim 14, wherein dimples are formed on a surface of at least one of said plurality of vanes.

Claim 30

The flow meter of claim 14, wherein bumps are formed on a surface of at least one of said plurality of vanes.

Claim 31

A meter for measuring a volumetric flow of a fluid in a conduit, which comprises: a first independent cantilever turbine assembly having a fixed end and a free end; a second independent cantilever turbine assembly having a fixed end and a free end; said first and second turbine assembly each having a plurality of rotor blades and each adapted to have a speed of rotation representative of the volumetric fluid flow; and a flow randomizer intermediate said first and second turbine assembly, said randomizer having a first end and a second end and at least one vane, said first end of said randomizer adapted to shroud at least a portion of said free end of said first turbine assembly; said second end of said randomizer adapted to shroud at least a portion of said free end of said second turbine assembly, said flow randomizer vane spaced from said rotor blades of said first and second turbine assembly by a predetermined distance.

Claim 32

A meter for measuring a volumetric flow of a fluid in a conduit, which comprises: a first independent cantilever turbine assembly having a fixed end and a free end; a second independent cantilever turbine assembly having a fixed end and a free end; said first and second turbine assembly each having a plurality of rotor blades and each adapted to have a speed of rotation representative of the volumetric fluid flow; and a flow randomizer intermediate said first and second turbine assembly, said randomizer having a first end and a second end and at least one vane, said first end of said randomizer adapted to shroud at least a portion of said free end of said first turbine assembly; said second end of said randomizer adapted to shroud at least a portion of said free end of said second turbine assembly, said flow randomizer vane spaced from said rotor blades of said first and second turbine assembly by a predetermined distance.

Claim 33

A meter for measuring a volumetric flow of a fluid in a conduit, which comprises: a first independent turbine assembly; a second independent turbine assembly; said first and second turbine assembly each having a plurality of rotor blades and each adapted to freely rotate at a speed representative of the volumetric fluid flow; a flow randomizer intermediate said first and second turbine assembly, said flow randomizer spaced from said rotor blades of said first turbine assembly a distance substantially equal to a distance at which a flow shear layer caused by said randomizer converges for a predetermined fluid flow.

Claim 34

A meter for measuring a volumetric flow of a fluid in a conduit, which comprises: a first independent turbine assembly; a second independent turbine assembly; said first and second turbine assembly each having a plurality of rotor blades and each adapted to freely rotate at a speed representative of the volumetric fluid flow; a flow randomizer intermediate said first and second turbine assembly, said flow randomizer spaced from said rotor blades of said first turbine assembly a distance substantially equal to a distance at which a flow shear layer caused by said randomizer converges for a predetermined fluid flow.

Claim 35

A volumetric fluid flow meter, which comprises: a first bi-directional, substantially non-magnetic turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second bi-directional, substantially non-magnetic turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first bi-directional turbine assembly and said second bi-directional turbine assembly, said randomizer having a plurality of vanes emanating radially from a central diffuser of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly, said randomizer spaced from a plane formed by leading edges of one of said turbine assemblies a distance of about 6 to 8 times an average randomizer vane thickness; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the speed of rotation of said first turbine; and a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine.

Claim 36

A volumetric fluid flow meter, which comprises: a first bi-directional, substantially non-magnetic turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to rotate at speeds representative of differing rates of fluid flow past said first turbine assembly; a second bi-directional, substantially non-magnetic turbine assembly, said turbine assembly having a vane assembly and a turbine having a plurality of substantially magnetic rotors, said turbine adapted to rotate at speeds representative of differing rates of fluid flow past said second turbine assembly; a flow randomizer located between said first bi-directional turbine assembly and said second bi-directional turbine assembly, said randomizer having a plurality of vanes emanating radially from a central diffuser of sufficient length to eliminate substantially all flow effects of one of said turbine assemblies upon the other turbine assembly, said randomizer spaced from a plane formed by leading edges of one of said turbine assemblies a distance of about 6 to 8 times an average randomizer vane thickness; a first magnetic pickup located adjacent said magnetic rotors of said first turbine assembly for transducing the speed of rotation of said first turbine; and a second magnetic pickup located adjacent said magnetic rotors of said second turbine assembly for transducing the speed of rotation of said second turbine.