A multichannel flow tube (300) for a vibratory meter (5), and a method of manufacturing the multichannel flow tube are provided. The multichannel flow tube comprises a tube perimeter wall (304), a first channel division (302b), and a first support structure (308a). The first channel division is enclosed within and coupled to the tube perimeter wall, forming a first channel (306b) and a second channel (306c). The first support structure is coupled to the tube perimeter wall and the first channel division.

Vibratory meters (5), and methods for their use measuring a fluid are provided. Each vibratory meter includes a multichannel flow tube (300) comprising two or more fluid channels (302), a pickoff (170), a driver (180), and meter electronics (20) configured to apply a drive signal to the driver at a drive frequency, and measure a deflection of the multichannel flow tube with the pickoff. In examples, at least one fluid channel has an effective diameter that is related to kinematic viscosity, inverse Stokes number, and drive frequency; velocity of sound and drive velocity; or the length of the flow tube. In further examples, the driver may apply a drive signal to the driver having a drive frequency proportional to the kinematic viscosity, inverse Stokes number, and effective diameter; or velocity of sound and effective diameter.

The invention relates to a method for ascertaining a physical parameter of a gas using a measuring transducer having a measuring tube for conveying the gas, wherein the measuring tube is excitable to execute bending oscillations of different modes and eigenfrequencies, the method includes: ascertaining the eigenfrequency of the f1-mode and f3-mode; ascertaining preliminary density values for the gas based on the eigenfrequencies of the f1-mode and f3-mode; ascertaining a value for the velocity of sound of the gas, and/or, dependent on the velocity of sound and the eigenfrequency of a mode, at least one correcting term and/or density error for the preliminary density value; and/or a correcting term for a preliminary mass flow value for determining a corrected mass flow measured value based on the first preliminary density value, the second preliminary density value, the eigenfrequencies of the f1-mode and f3-mode.

A flowmeter (5) is provided. The flowmeter (5) has a wetted assembly (200) comprising one or more conduits (208, 208), and at least one driver magnet (218, 218) attached to the one or more conduits (208, 208). A dry assembly (202) houses a driver coil (224), and meter electronics (20) are in electrical communication with the driver coil (224). A case (236) at least partially covers the wetted assembly (200) and the dry assembly (202). The dry assembly (202) is removably attachable to the wetted assembly (200). The driver coil (224) is in magnetic communication with the at least one driver magnet (218, 218) when the dry assembly (202) is attached to the wetted assembly (200), and the driver coil (224) is configured to provide a vibratory signal to the at least one driver magnet (218, 218) when the dry assembly (202) is attached to the wetted assembly (200).

A first and second vibratory meter (5), and methods of manufacturing the same are provided. The first vibratory meter includes a pickoff (170l), a driver (180), and a flow tube (400) comprising a tube perimeter wall with: a first substantially planar section (406a), a second substantially planar section (406b) coupled to the first substantially planar section to form a first angle ?1#191 (404), and a first curved section (406c). The second vibratory meter includes a pickoff, a driver, and a flow tube (700) comprising a tube perimeter wall with: a first substantially planar section (706a), a second substantially planar section (706b) coupled to the first substantially planar section to form a first angle ?1#191 (704), a third substantially planar section (706c), a fourth substantially planar section (706d), and a fifth substantially planar section (706e).

Vibratory meters (5), and methods for their use measuring a fluid are provided. Each vibratory meter includes a multichannel flow tube (300) comprising two or more fluid channels (302), a pickoff (170), a driver (180), and meter electronics (20) configured to apply a drive signal to the driver at a drive frequency , and measure a deflection of the multichannel flow tube with the pickoff. In examples, at least one fluid channel has an effective diameter that is related to kinematic viscosity, inverse Stokes number, and drive frequency. In further examples, the driver may apply a drive signal to the driver having a drive frequency proportional to the kinematic viscosity, inverse Stokes number, and effective diameter.

Vibratory meters (5), and methods for their use measuring a fluid are provided. Each vibratory meter includes a multichannel flow tube (300) comprising two or more fluid channels (302), a pickoff (170), a driver (180), and meter electronics (20) configured to apply a drive signal to the driver at a drive frequency , and measure a deflection of the multichannel flow tube with the pickoff. In examples, at least one fluid channel has an effective diameter that is related to velocity of sound and drive velocity. In further examples, the driver may apply a drive signal to the driver having a drive frequency proportional to the velocity of sound and effective diameter.

A vibratory meter (5), and methods of manufacturing the same are provided. The vibratory meter includes a pickoff, a driver, and a flow tube (700) comprising a tube perimeter wall with: a first substantially planar section (706a), a second substantially planar section (706b) coupled to the first substantially planar section to form a first angle .sub.1 (704), a third substantially planar section (706c), a fourth substantially planar section (706d), and a fifth substantially planar section (706e).

A system (800) for minimizing a crest in a multi-tone drive signal in a vibratory meter (5) is provided. The system (800) includes a drive signal generator (810) configured to generate the multi-tone drive signal for the vibratory meter (5) and a drive signal detector (820). The drive signal detector (820) is configured to receive the multi-tone drive signal, determine a first maximum amplitude of the multi-tone drive signal having a component at a first phase, determine a second maximum amplitude of the multi-tone drive signal having the component at a second phase, and compare the first maximum amplitude and the second maximum amplitude.

A method for operating a Coriolis mass flowmeter having at least one measuring tube, at least one oscillation generator, at least two oscillation sensors, and at least one control and evaluation unit, the oscillation generator and the oscillation sensors being arranged on the measuring tube, wherein the measuring tube has a medium flowing through it, wherein the oscillation generator puts the measuring tube into a harmonic oscillation with the excitation frequency f.sub.0 and the excitation amplitude A.sub.0, wherein the first and the second oscillation sensors detect the oscillation of the measuring tube and wherein the first oscillation sensor forwards the oscillation to the control and evaluation unit as first measuring signal and wherein the second oscillation sensor forwards the oscillation to the control and evaluation unit as second measuring signal, and wherein at least one comparison measurement signal is determined from the first measuring signal and/or the second measuring signal.