US 12,264,949 B2
Gas flow estimation method, hole diameter estimation method, gas flow rate estimation device, and hole diameter estimation device
Hajime Yoshida, Tsukuba (JP); Yoshinori Takei, Tsukuba (JP); Kenta Arai, Tsukuba (JP); Mao Hirata, Tokyo (JP); Tsutomu Hara, Tokyo (JP); and Jun Inomata, Tokyo (JP)
Assigned to NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, Tokyo (JP); and FUKUDA CO., LTD., Tokyo (JP)
Appl. No. 17/764,304
Filed by NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, Tokyo (JP); and FUKUDA CO., LTD., Tokyo (JP)
PCT Filed Oct. 16, 2020, PCT No. PCT/JP2020/039118
§ 371(c)(1), (2) Date Mar. 28, 2022,
PCT Pub. No. WO2021/079833, PCT Pub. Date Apr. 29, 2021.
Claims priority of application No. 2019-194488 (JP), filed on Oct. 25, 2019.
Prior Publication US 2022/0349735 A1, Nov. 3, 2022
Int. Cl. G06F 11/30 (2006.01); G01F 1/34 (2006.01); G01M 3/28 (2006.01); G06F 113/08 (2020.01)
CPC G01F 1/34 (2013.01) [G01M 3/28 (2013.01); G06F 2113/08 (2020.01)] 12 Claims
OG exemplary drawing
 
1. A gas flow rate estimation method, comprising:
determining a flow rate of gas flowing through a hole by a computation unit, based on a type of the gas flowing through the hole, pressures upstream and downstream from the hole, and information about the hole, wherein
the flow rate of the gas is determined by the computation unit, regardless of a state of flow of the gas, from a molecular weight, a viscosity coefficient, and a specific heat ratio of the gas, a diameter and a length of the hole, and the upstream and downstream pressures of the gas flowing through the hole, based on a predetermined relational expression including, as parameters, all of the flow rate of the gas, the diameter of the hole, the length of the hole, the upstream and downstream pressures of the hole, a temperature of the gas, the molecular weight of the gas, the viscosity coefficient of the gas, and the specific heat ratio of the gas, and
the predetermined relational expression includes Qc represented by the following expression:

OG Complex Work Unit Math
where Qc is the flow rate of the gas under assumption of continuous flow, QVL is the flow rate of the gas under assumption of laminar flow, QTB is the flow rate of the gas under assumption of turbulent flow, and QCF′ is the flow rate of the gas under assumption of compressible flow.