Disclosed is a method for determining of fat content of milk having variable solids fractions and flowing with variable gas content in a pipeline. The method includes ascertaining a velocity of sound and an average density value for the milk based on eigenfrequencies of at least two bending oscillation wanted modes of measuring tubes of a densimeter arranged in the pipeline. The method further includes ascertaining a static pressure in the pipeline; a gas volume fraction based on the velocity of sound; the average density; the pressure; a density of the milk without gas content based on the average density and the gas volume fraction; and a permittivity of the milk based on a propagation velocity and/or an absorption of microwaves in the milk. The fat fraction is calculated based on the density of the milk without gas content and on the effective permittivity.

A spool body is provided that is adapted for use in a vibrating densitometer. The spool body comprises a core and a plurality of spines that emanate distally from the core. At least one channel is defined by the plurality of spines, wherein a cantilever mode of the spool body lies outside a predetermined natural frequency range of a vibrating tube portion of the vibrating densitometer.

A vibrating meter (100) is provided being operable to determine at least one of a viscosity and a density of a fluid therein. The vibrating meter (100) comprises a driver (112), a vibrating element (104) vibratable by the driver (112), and operable to be in contact with the fluid. A vibrating sensor (114) is configured to detect a vibrational response of the vibrating element (104). Meter electronics (118) is configured to send an excitation signal to the driver (112) and to receive the vibrational response and is further configured to measure a first vibrational response point and a second vibrational response point of the vibrational response. The second vibrational response point is one of interpolated and extrapolated from other measured response points. The meter electronics (118) is further configured to calculate a Q of the vibrating element (104) using the first vibrational response point and the second vibrational response point.

A device for determining and/or monitoring a process variable of a medium comprises a sensor unit with a mechanically vibrating fork having a first and a second vibrating element and having a first piezoelectric element arranged in the first vibrating element. An electronic unit of the device is designed to excite mechanical vibrations in the mechanically vibratable unit, receive the mechanical vibrations of the vibratable unit and convert same into a first reception signal, generate the excitation signal on the basis of the first reception signal such that there is a specifiable phase shift between the excitation signal and the first reception signal, and ascertain the process variable using the first reception signal. The electronic unit has an adjustable impedance element connected in series to the first piezoelectric element.

A vibronic sensor used to determine a process variable of a medium in a container comprises a mechanically vibratable unit, a drive/receiving unit, and an electronic unit. The drive/receiving unit excites mechanical vibrations in the mechanically vibratable unit via an electric excitation signal and receives the mechanical vibrations of the mechanically vibratable unit and convert same into an electric reception signal. The electronic unit is designed to generate the excitation signal on the basis of the reception signal and determine the process variable from the reception signal. The electronic unit includes an adaptive filter and is designed to set the filter characteristic of the adapter filter to produce a target phase offset between the excitation and reception signals. The sensor also has a detection unit to determine a phase offset between the excitation signal and the reception signal and/or the amplitude of the reception signal using a quadrature demodulation.

Described is a device for measuring fluid density. The device is a flow meter including a housing with one side configured to mount to a flow conduit and define an outlet flow orifice near one end of the housing. The other side defines an inlet flow orifice near another end of the housing. The housing permits fluid to be introduced into the inlet flow orifice, flow through a flow cavity, and pass from the outlet flow orifice. The flow meter also includes a sensor head near the outlet flow orifice. The sensor head vibrates at a frequency upon introduction of electrical power while in contact with a fluid, detects the vibration frequency of the sensor head, and transmits the detected vibration frequency, which is associated with a density of the fluid. A system and method for determining a fluid density of a fluid using the described device is also disclosed.

Disclosed are a gas density relay having a simulation check function and a simulation check method thereof, the gas density relay includes a gas density relay body, a simulation reference signal unit, a simulation check signal unit, a driving contact action mechanism, and an intelligent control unit. The intelligent control unit obtains, according to the check, by the simulation reference signal unit, of a simulation check signal generated by the simulation check signal unit, a current working state of a monitoring part, so as to quantitatively and accurately measure the precision of the gas density relay; by providing the driving contact action mechanism, the gas density relay body generates an alarm and/or a locking contact action to ensure that a contact execution mechanism of the gas density relay body and a contact itself are normal. The present application completes online simulation or virtual check of the gas density relay while being used for monitoring the gas density of a insulation or arc extinguishing electrical equipment, thereby improving working efficiency, reducing operation and maintenance costs, and guaranteeing safe operation of a power grid.

A device for determining and/or monitoring a process variable of a medium includes a sensor unit having a mechanically oscillatable unit, a first piezoelectric element, a unit for determining and/or monitoring a temperature of the medium and an electronic system. The device is designed to excite the mechanically oscillatable unit and to receive the mechanical oscillations of the oscillatable unit, to convert them into a first receiving signal, to emit a transmission signal and to receive a second receiving signal, wherein the electronic system is designed to determine the process variable based on the first and/or second receiving signal. The unit for determining and/or monitoring the temperature includes a first and a second temperature sensor arranged at a distance from one another, and the electronic system is designed to determine the temperature of the medium based on a first and/or second temperature receiving signal.

Methods of forming a shear-mode chemical/physical sensor for liquid environment sensing on V-shaped grooves of a [100] crystal orientation Si layer and the resulting devices are provided. Embodiments include forming a set of V-shaped grooves in a [100] Si layer over a substrate; forming an acoustic resonator over and along the V-shaped grooves, the acoustic resonator including a first metal layer, a thin-film piezoelectric layer, and a second metal layer in an IDT pattern or a sheet; and forming at least one functional layer along a slope of the acoustic resonator.

The method of the present disclosure for signaling a standard frequency of a density meter comprises: exciting bending vibrations of a measurement tube at an excitation mode working frequency, the working frequency depending on the density of a medium conducted in the measurement tube and on a disturbance variable; determining a characteristic value of the working frequency; determining a value representing the disturbance variable; calculating a corrected density value of the medium as a function of the characteristic value of the working frequency and of the value representing the disturbance variable; calculating a characteristic value of the standard frequency as a function of the corrected density value, the standard frequency being the frequency which produces the corrected density value in a calculation of the density using a frequency-dependent standard function which is not dependent on the disturbance variable; and providing a signal representing the standard frequency.