Correcting for two-phase flow in a digital flowmeter

PROBLEM TO BE SOLVED: To provide a Coriolis-type mass flowmeter capable of performing accurate measurement regardless of a change of a flow state of a fluid. ;SOLUTION: A controller includes: a generation means generating a raw mass flow rate measurement value from a sensor signal; a decision means deciding whether a state inside a conduit of the fluid is a single-phase flow state or a two-phase flow state; a first process execution means executing a first process for processing the raw mass flow rate measurement value to generate a first mass flow rate measurement value during the single-phase flow state when the decision means decides that it is the single-phase flow state; and a second process execution means executing a second process for generating a second mass flow rate measurement value during the two-phase flow state when the decision means decides that it is the two-phase flow state. The second process execution means includes: an error correction factor generation means generating an error correction factor on the basis of the raw mass flow rate measurement value; and a correction means correcting the raw mass flow rate measurement value by arithmetic processing by use of the error correction factor. ;COPYRIGHT: (C)2008,JPO&INPIT