US 11,927,463 B2
Measurement system, measurement device, and measurement method to detect a direction in which fluid flows
Yutaka Yano, Tokyo (JP); Eitaro Misumi, Tokyo (JP); and Makoto Saitoh, Tokyo (JP)
Assigned to NEC CORPORATION, Tokyo (JP)
Appl. No. 17/777,665
Filed by NEC Corporation, Tokyo (JP)
PCT Filed Aug. 25, 2020, PCT No. PCT/JP2020/031944
§ 371(c)(1), (2) Date May 18, 2022,
PCT Pub. No. WO2021/100274, PCT Pub. Date May 27, 2021.
Claims priority of application No. 2019-209868 (JP), filed on Nov. 20, 2019.
Prior Publication US 2023/0043442 A1, Feb. 9, 2023
Int. Cl. G01D 5/353 (2006.01); G01F 1/32 (2022.01); G01F 1/661 (2022.01); G01H 9/00 (2006.01)
CPC G01D 5/35358 (2013.01) [G01F 1/3209 (2013.01); G01F 1/661 (2013.01); G01H 9/004 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A measurement system comprising:
an object provided in a fluid, and configured to generate a self-excited vibration by the fluid;
an optical fiber provided in the fluid, and configured to detect the vibration;
a light source configured to output light to the optical fiber;
a detector configured to acquire backscattered light that is generated from the light in the optical fiber and includes a pattern indicating the vibration in a vibration position on the optical fiber to which the vibration of the fluid is transmitted; and
a calculator configured to measure, from a pattern that is included in the backscattered light and indicates the vibration, a flow speed of the fluid in the vibration position,
wherein an object configured to generate a self-excited vibration by the fluid 1 s integrated as an optical fiber cable including the optical fiber configured to detect the vibration,
wherein the optical fiber configured to detect the vibration is disposed in a plurality of directions, and thus has a plurality of vibration detection sections at different angles formed with a flow of the fluid, and
wherein the calculator is configured to perform a comparison analysis on the vibration in each of the vibration detection sections, and to also detect a direction in which the fluid flows, using a comparison result.