US 6,578,414 B2 · Split-flow-type flowmeter

Abstract

A split-flow-type flowmeter in which an end portion of a flow splitter tube 1 is inserted into a main-flow pipe 10 having a diameter D. A flow splitter tube 1 includes a U-shaped split-flow passage 1a. A detection element is disposed at a bottom portion (not shown) of the U-shaped split-flow passage 1a. The split-flow passage 1a assumes a flow path structure symmetrical with respect to a plane passing through the detection element. A flow inlet 2a and a flow outlet 2b of the split-flow passage 1a face in mutually opposite directions along the flow direction of the main-flow pipe 10 and open symmetrically at the same position on the flow cross section of the main-flow pipe 10. In order to divert into the split-flow passage 1a a portion of relatively high flow rate of flow from the main-flow pipe 10, the center of opening of the flow inlet 2a/flow outlet 2b is positioned between the center of the flow cross section of the main-flow pipe 10 and an average-flow-velocity position at which flow in the main-flow pipe 10 is of an average flow velocity, as observed on the flow cross section of the main-flow pipe 10.

Claims18

Dependent claims

the split-flow passage assumes a flow path structure that is symmetrical with respect to a plane passing through the detection element and being parallel to a flow cross section of the main-flow pipe;
a flow inlet and a flow outlet of the split-flow passage open in opposition to each other along a flow direction in the main-flow pipe and are symmetrically positioned with respect to the flow cross section of the main-flow pipe;
a center of opening of the flow inlet and the flow outlet of the split-flow passage is positioned between a center of the flow cross section of the main-flow pipe and an average-flow-velocity position at which flow in the main-flow pipe is of an average flow velocity, as observed on the flow cross section of the main-flow pipe,
whereby a regular-flow component and a backflow component of the pulsating flow arising in the main-flow pipe can be measured equivalently.

1 more element

A split-flow flowmeter for detecting a portion of flow diverted from a main-flow pipe into a split-flow passage, by use of a detection element facing the interior of the split-flow passage so as to measure a flow rate in the main-flow pipe, and adapted for measuring a pulsating flow arising in the main-flow pipe, comprising an introduction unit inserted into the main-flow pipe and having a flow inlet for diverting therein a portion of flow from the main-flow pipe, a flow outlet for discharging the portion of flow, and a first flow path communicating with the flow inlet and the flow outlet and that is symmetrical with respect to a predetermined plane;

and a detection unit having a second flow path that is symmetrical with respect to the predetermined plane and the detection element exposed to flow within the second flow path, wherein
the introduction unit and the detection unit are integrally attached to the main-flow pipe;
the first flow path and the second flow path communicate with each other to thereby establish the split-flow passage;
and
the predetermined plane passes through the detection element and is parallel to a flow cross section of the main-flow pipe;
whereby a regular-flow component and a backflow component of the pulsating flow arising in the main-flow pipe can be measured equivalently.

3 more elements

Dependencies are inferred from the claim text.

Split-flow-type flowmeter

Life of this patent

Split-flow-type flowmeter

Life of this patent

Abstract

Claims18