Flow measurement and control device and associated method
View Patent ↗A fluid flow device includes a body with an internal flow path that expands then contracts, the internal flow path having an inlet, a first region having a first cross-sectional area (A 1 ), a second region having a second cross-sectional area (A 2 ), a third region having a third cross-sectional area (A 3 ), and an outlet, where A 2 >A 1 , and where a minimum cross-sectional area (Amin) of the internal flow path between the inlet and the outlet is equal to or greater than AR·A 1 , with AR≥0.70. A high-pressure manifold fluidically connects to the internal flow path at the second cross-sectional area (A 2 ), a first low-pressure manifold fluidically connects to the internal flow path at the first cross-sectional area (A 1 ) and/or at the third cross-sectional area (A 3 ), and a first sensor is operatively connected to the high-pressure and first low-pressure manifolds to sense a pressure differential.
1 . A fluid flow device comprising:
a body with an internal flow path that expands then contracts in a direction of fluid flow, the internal flow path having an inlet, a first region having a first cross-sectional area (A 1 ), a second region having a second cross-sectional area (A 2 ), a third region having a third cross-sectional area (A 3 ), and an outlet, wherein the first, second, and third regions are each located in between the inlet and the outlet, wherein A 2 >A 1 , and wherein a minimum cross-sectional area (Amin) of the internal flow path between the inlet and the outlet is equal to or greater than AR·A 1 , where AR≥0.70;
a high-pressure manifold fluidically connected to the internal flow path at the second cross-sectional area (A 2 );
a first low-pressure manifold fluidically connected to the internal flow path at the first cross-sectional area (A 1 ), at the third cross-sectional area (A 3 ), or at both the first and third cross-sectional areas (A 1 and A 3 ); and
a first sensor operatively connected to the high-pressure manifold and the first low-pressure manifold, the first sensor configured to sense a pressure differential.
2 . The fluid flow device of claim 1 and further comprising:
a plateau region having a substantially constant area, wherein the second cross-sectional area (A 2 ) is located at or within the plateau region.
3 . The fluid flow device of claim 1 , wherein the first and third cross-sectional areas (A 1 and A 3 ) are substantially equal.
4 . The fluid flow device of claim 1 , wherein the first cross-sectional area (A 1 ) is located upstream of the second cross-sectional area (A 2 ) and the first region adjoins the inlet, and wherein the second cross-sectional area (A 2 ) is located upstream of the third cross-sectional area (A 3 ) and the third region adjoins the outlet, such that, in a direction of flow, the internal flow path expands in an expansion zone located between the first and second cross-sectional areas (A 1 and A 2 ) and then contracts in a contraction zone located between the second and third cross-sectional areas (A 2 and A 3 ).
5 . The fluid flow device of claim 1 and further comprising:
a second low-pressure manifold, wherein the first low-pressure manifold is fluidically connected to the internal flow path at the first cross-sectional area (A 1 ), and wherein the second low-pressure manifold is fluidically connected to the internal flow path at the third cross-sectional area (A 3 ).
6 . The fluid flow device of claim 5 , wherein the first sensor is further operatively connected to the second low-pressure manifold.
7 . The fluid flow device of claim 5 and further comprising:
a second sensor operatively connected to the high-pressure manifold and the second low-pressure manifold, the second sensor configured to sense a pressure differential.
8 . The fluid flow device of claim 1 , wherein the high-pressure manifold includes a channel open to the internal flow path along at least a portion of a perimeter of the second cross-sectional area (A 2 ).
9 . The fluid flow device of claim 8 , wherein the channel is open to the internal flow path along substantially the entire perimeter of the second cross-sectional area (A 2 ).
10 . The fluid flow device of claim 8 , wherein the channel is canted.
11 . The fluid flow device of claim 1 , wherein the high-pressure manifold includes a plurality of openings in fluid communication with the internal flow path, wherein the plurality of openings are circumferentially-spaced from each other along a perimeter of the second cross-sectional area (A 2 ).
12 . The fluid flow device of claim 1 , wherein the internal flow path has a substantially constant area immediately upstream of the first cross-sectional area (A 1 ), and wherein the internal flow path has a substantially constant area immediately downstream of the third cross-sectional area (A 3 ).
13 . The fluid flow device of claim 1 and further comprising:
a damper positioned in the internal flow path; and
a controller operatively coupled to the first sensor and the damper, the controller configured to regulate a position of the damper in response to the sensed pressure differential to control volumetric flow.
14 . The fluid flow device of claim 1 , wherein the internal flow path is asymmetrical at least at a perimeter of the second cross-sectional area (A 2 ).
15 . The fluid flow device of claim 1 , wherein Amin≈A 1 ≈A 3 .
16 . A method of operating a fluid flow device, the method comprising:
moving a fluid through an internal flow path that expands and then contracts in a direction of fluid flow, the internal flow path having a first cross-sectional area (A 1 ) at a first position, a second cross-sectional area (A 2 ) at a second position, and a third cross-sectional area (A 3 ) at a third position, wherein the first, second, and third positions are at different locations along the internal flow path, wherein A 2 >A 1 , and wherein A 3 is equal to or greater than AR·A 1 , where AR≥0.70; and
measuring a pressure differential between a high-pressure manifold and at least one low-pressure manifold, wherein the high-pressure manifold is fluidically connected to the internal flow path at the second cross-sectional area (A 2 ), and wherein the at least one low-pressure manifold is fluidically connected to the internal flow path at the first cross-sectional area (A 1 ), at the third cross-sectional area (A 3 ), or at both the first and third cross-sectional areas (A 1 and A 3 ).
17 . The method of claim 16 , wherein the first cross-sectional area (A 1 ) is located upstream of the second cross-sectional area (A 2 ), and wherein the second cross-sectional area (A 2 ) is located upstream of the third cross-sectional area (A 3 ), the method further comprising expanding the fluid in the internal flow path in an expansion zone located between the first and second cross-sectional areas (A 1 and A 2 ) and constricting the fluid in the internal flow path in a contraction zone located between the second and third cross-sectional areas (A 2 and A 3 ).
18 . The method of claim 16 , wherein the step of moving the fluid through an internal flow path includes expanding the fluid asymmetrically relative to a centerline of the internal flow path.
19 . The method of claim 16 and further comprising:
actuating a damper as a function of the sensed pressure differential to control volumetric flow along the internal flow path.
20 . The method of claim 16 , wherein a minimum cross-sectional area (Amin) of the internal flow path between an inlet and an outlet satisfies Amin≈A 1 ≈A 3 .
21 . The method of claim 16 , wherein the fluid is moved along the internal flow path from an inlet followed by an expansion zone downstream from the inlet that expands in cross-sectional area, followed by a constriction zone downstream from the expansion zone that contracts in cross-sectional area, and then to an outlet, wherein a minimum cross-sectional area of the internal flow path is substantially the same between (a) the inlet and the expansion zone and (b) the expansion zone and the outlet.
22 . The method of claim 16 wherein the measured pressure differential is measured at a single measurement zone extending from the second cross-sectional area (A 2 ) either upstream or downstream to just one of the first cross-sectional area (A 1 ) or the third cross-sectional area (A 3 ).
23 . The method of claim 16 , wherein the measured pressure differential is either an average or combination of a plurality of pressure differential values collected at different zones along the internal flow path.
24 . The method of claim 16 , wherein the measured pressure differential includes both a static pressure component and a velocity pressure component.
25 . A fluid flow assembly comprising:
a body with an internal flow path that expands then contracts in a direction of fluid flow, the internal flow path having an inlet, a first region located downstream of the inlet and having a first cross-sectional area (A 1 ), a second region located downstream of the first region and having a second cross-sectional area (A 2 ), a third region located downstream of the second region having a third cross-sectional area (A 3 ), and an outlet located downstream of the third region, wherein A 2 >A 1 , and wherein a minimum cross-sectional area (Amin) of the internal flow path between the inlet and the outlet satisfies the relationship Amin≈A 1 ≈A 3 ;
a high-pressure manifold fluidically connected to the internal flow path at the second cross-sectional area (A 2 );
a first low-pressure manifold fluidically connected to the internal flow path, wherein the first low-pressure manifold is located at or adjacent to a perimeter of the first cross-sectional area (A 1 );
a second low-pressure manifold fluidically connected to the internal flow path, wherein the second low-pressure manifold is located at or adjacent to a perimeter of the third cross-sectional area (A 3 );
a first transducer operatively connected to the high-pressure manifold and to at least one of the first low-pressure manifold and the second low-pressure manifold, the first transducer configured to sense a pressure differential;
a damper positioned in the internal flow path; and
a controller operatively coupled to the first transducer and the damper, the controller configured to regulate a position of the damper in response to the sensed pressure differential to control volumetric flow.
26 . The fluid flow assembly of claim 25 , wherein the first transducer is operatively connected to both the first and second low-pressure manifolds.
27 . The fluid flow assembly of claim 25 and further comprising:
a second transducer operatively connected to the high-pressure manifold and to the second low-pressure manifold, the second transducer configured to sense a pressure differential, and wherein the first transducer is operatively connected to the first low-pressure manifold.