Patent classifications
G01F1/849
Coriolis frequency tracking
Motion is induced in a conduit such that the conduit vibrates in a major mode of vibration having a major amplitude and a minor mode of vibration having a minor amplitude. The major amplitude is larger than the minor amplitude, the major mode of vibration has a first frequency of vibration and the minor mode of vibration has a second frequency of vibration, and the minor mode of vibration interferes with the major mode of vibration to cause a beat signal having a frequency related to the first frequency of vibration and the second frequency of vibration. The frequency of the beat signal is determined, and the second frequency of vibration is determined based on the determined frequency of the beat signal.
VISCOMETER
The viscometer provides a viscosity value (X.sub.0) which represents the viscosity of a fluid flowing in a pipe connected thereto. It comprises a vibratory transducer with at least one flow tube for conducting the fluid, which communicates with the pipe. Driven by an excitation assembly, the flow tube is vibrated so that friction forces are produced in the fluid. The viscometer further includes meter electronics which feed an excitation current (i.sub.exc) into the excitation assembly. By means of the meter electronics, a first internal intermediate value (X.sub.1) is formed, which corresponds with the excitation current (i.sub.exc) and thus represents the friction forces acting in the fluid. According to the invention, a second internal intermediate value (X.sub.2), representing inhomogeneities in the fluid, is generated in the meter electronics, which then determine the viscosity value (X.sub.0) using the two intermediate values (X.sub.1, X.sub.2). The first internal intermediate value (X.sub.1) is preferably normalized by means of an amplitude control signal (y.sub.AM) for the excitation current (i.sub.exc), the amplitude control signal corresponding with the vibrations of the flow tube. As a result, the viscosity value (X.sub.0) provided by the viscometer is highly accurate and robust, particularly independently of the position of installation of the flow tube.
METHOD FOR OPERATING A CORIOLIS MASS FLOWMETER AND CORIOLIS MASS FLOWMETER
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.
Measuring System Having a Measuring Transducer of Vibration-Type
A measuring system comprises: a measuring transducer; transmitter electronics; at least one measuring tube; and at least one oscillation exciter. The transmitter electronics delivers a driver signal for the at least one oscillation exciter, and for feeding electrical, excitation power into the at least one oscillation exciter. The driver signal, has a sinusoidal signal component which corresponds to an instantaneous eigenfrequency, and in which the at least one measuring tube can execute, or executes, eigenoscillations about a resting position. The eigenoscillations have an oscillation node and in the region of the wanted, oscillatory length exactly one oscillatory antinode. The driver signal has, a sinusoidal signal component with a signal frequency, which deviates from each instantaneous eigenfrequency of each natural mode of oscillation of the at least one measuring tube, in each case, by more than 1 Hz and/or by more than 1% of said eigenfrequency.
FUEL DISPENSER HAVING ACOUSTIC WAVES CORIOLIS FLOW METER
A fuel dispenser comprises a fuel nozzle configured to be connected to a vehicle fuel system. Fuel piping configured to transfer fuel from at least one fuel storage tank associated with the fuel dispenser through the fuel nozzle into the vehicle fuel system is also provided. A flow control valve and a flow measurement device are located along the fuel piping, the flow measurement device having a housing defining a flow path therethrough. The flow measurement device includes a first exciter for producing a first wave in fuel moving along the flow path. A second exciter produces a second wave in the fuel which passes through the first wave, wherein the second wave has a higher frequency than the first wave. At least one sensor is spaced apart from the first exciter and the second exciter, the at least one sensor being configured to detect at least one measurable characteristic of the second wave from which flow rate can be derived.
Fluid parameter sensor and meter
An example fluid parameter sensor and meter is disclosed to measure at least one parameter of a fluid. In an example, the fluid parameter meter includes an outer conduit. A sensor element assembly is disposed in the outer conduit and has at least one straight uniform sensor element with an open interior to convey the fluid inside of the sensor element assembly. At least one mounting flexure is fixedly attached to the sensor element assembly and to the outer conduit. The at least one mounting flexure is configured to enable the sensor element assembly to vibrate in a natural radial mode shape of vibration. At least one vibration driver causes the sensor element assembly to vibrate. At least one vibration sensor senses the vibration of the sensor element assembly.
METHOD FOR OPERATING A CORIOLIS MASS FLOWMETER AND ASSOCIATED CORIOLIS MASS FLOWMETER
A method for operating a Coriolis mass flowmeter having at least one measuring tube, at least one oscillation generator, at least one oscillation sensor and at least one strain sensor. The oscillation generator is actuated with an oscillation excitation signal and the measuring tube is excited to oscillation by the oscillation generator, the oscillation of the measuring tube is detected by the oscillation sensor and an oscillation sensor signal is generated. The strain sensor is mechanically coupled to the measuring tube via a connection. A change of the mechanical coupling via the connection can be determined by the oscillation of the measuring tube being measured by the strain sensor and a strain sensor signal generated representing oscillation of the measuring tube, a correlation between the strain sensor signal and an oscillation signal representing the oscillation of the measuring tube is identified, and a temporal change of the correlation is determined.
METHOD FOR OPERATING A CORIOLIS MASS FLOWMETER AND CORRESPONDING CORIOLIS MASS FLOWMETER
A method for operating a Coriolis mass flowmeter having at least one controller, at least one electric actuating device, at least one electromagnetic driving mechanism with a drive coil as oscillation generator, at least one measuring tube and at least one oscillation sensor involves excited oscillation of the measuring tube being detected by the oscillation sensor and emitted as at least one output signal and the electric actuating device causing the electromagnetic driving mechanism to produce oscillation of the measuring tube largely in resonance by the output signal of the oscillation sensor, the drive voltage at the drive coil, and phasing of the drive current in relation to the phasing of the output signal of the oscillation sensor being determined and a new target phasing for the drive voltage derived from the determinations and supplied to the controller to generate a drive voltage with the new target phasing.
To reduce strain in coriolis flow sensor
An embodiment of a balance bar (230) is disclosed. The balance bar (230) comprises a first side portion (231) having a hollow interior for receiving a flow tube (220), a central portion (233) having a hollow interior for receiving a flow tube (220), and a first side flexible portion (234) comprising at least one flexible coupler (250), the first side flexible portion (234) coupling the first side portion (231) with the central portion (233), wherein the first side portion (231) and the central portion (233) are both more rigid than the first side flexible portion (234).
INTEGRATED CORIOLIS MASS FLOW METERS
An integrated flow meter includes a support and one or more flow sensitive member(s) integrated with the support. The support is formed by using an injection molding process that overmolds material over an outer surface of the flow sensitive member(s). The materials for the support and for the flow sensitive member(s) preferably are polymeric materials.