FLOW-RATE MEASUREMENT DEVICE AND FLOW-RATE MEASUREMENT METHOD

• Main Authors: KOBATA, Iwao, SUZUKI, Hiroshi, NAKAYA, Mitsuyoshi
• Format: Patent
• Language: English; French; German
• Published: 17.02.2021
• Subjects: MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; METERING BY VOLUME; PHYSICS; TESTING

Provided are a flow rate measurement device and a flow rate measurement method capable of accurately measuring flow rates not only in a turbulent flow region but also in a laminar flow region and a transition region. A processor includes: a parameter generator that obtains a reference differential pressure in a flow rate calculation formula of expression 1 as follows, based on already-known flow rates and measured differential pressures corresponding thereto, and generates two parameter sets each including coefficients c1 to c3 of the flow rate calculation formula, with the reference differential pressure being a boundary; a differential pressure determination unit that selects one of the two parameter sets by comparing a measured differential pressure of a fluid as a measurement target with the reference differential pressure; and a flow rate calculator that calculates a flow rate of the fluid from the parameter set and the measured differential pressure. ΔP=c1×η×Q+c2×ρ×Q2+c3 (Q: flow rate, ΔP: differential pressure, η: coefficient of kinematic viscosity, ρ: density, c1 to c3: coefficients)