A device and a method for determining and/or monitoring at least one process variable of a medium include a sensor unit having a mechanically oscillatable unit, at least a first piezoelectric element, a temperature detection unit for determining and/or monitoring a temperature of the medium and an electronics unit. The device is embodied to excite the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, to receive mechanical oscillations of the oscillatable unit and convert them into a first received signal, to transmit a transmitted signal and to receive a second received signal. The electronics unit is embodied, based on the first and/or second received signal, to determine the at least one process variable and, based on a third received signal received from the temperature detection unit, to determine the temperature of the medium.

A method for the measurement of a physical parameter of a liquid by means of a sensor having at least one measuring tube for conducting the liquid, wherein the measuring tube can be excited to vibrate in at least one flexural vibration mode, comprises: determining at least one current value of a vibration parameter of the flexural vibration mode; determining a measurement value of the physical parameter according to the current value of the vibration parameter, wherein the measurement value is compensated in respect of the resonator effect according to a current value for the natural frequency of the flexural vibration mode and according to the sound velocity of the liquid conducted in the measuring tube, wherein the value for the sound velocity is provided independently of the vibrations of the measuring tube.

The invention provides a method of driving a vibrating sensor in which the drive signal is combined with an amplitude modulated high frequency carrier. The signal is demodulated at a position adjacent to the component to be driven. This method may be applied to reducing cross-talk between drive and pick-up wire pairs and also to passing both drive and pickup signals, and two drive signals, down the same wire pair.

A densitometer in the present disclosure comprises a piston attached to an end of a tube of the densitometer to reduce pressure dependence of density estimates of a sample fluid. The densitometer measures sample fluid density by vibrating the tube containing sample fluid and measuring the resonant frequency of the tube, then estimating the sample fluid density based on this resonant frequency. The piston is designed with a predetermined diameter that converts pressure inside the tube to tension in the tube. This tension produces an opposite effect on the resonant frequency of the tube to that caused by the fluid pressure itself and thereby reduces pressure dependence of the sample fluid density estimates.

A device and a method for determining and/or monitoring at least one process variable of a medium include a sensor unit having a mechanically oscillatable unit, at least a first piezoelectric element, a conductivity/capacitance detecting unit for determining and/or monitoring a conductivity and/or capacitance of the medium and an electronics unit. The device is embodied to excite the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, to receive the mechanical oscillations of the oscillatable unit, to convert them into a first received signal, to transmit a transmitted signal, and to receive a second received signal. The electronics unit is embodied, based on the first and/or second received signal, to determine the at least one process variable of the medium.

The present disclosure relates to a method for calculating a quality pertaining to at least one measuring tube of a Coriolis measuring device for measuring a density or a mass flow of a medium flowing through the measuring tube, wherein a determination regarding a state of the measuring tube can be made by determining various vibration properties.

A method for determining a measurement error caused by a filling error, in particular the presence of gas bubbles, during measurement of the density of a liquid by means of a densimeter having a flexural resonator containing the liquid to be measured. During a measuring operation, a period duration of an oscillation of the flexural resonator induced by an induction unit is measured by a measuring device and the density of the liquid is determined by an evaluation unit.

The present disclosure relates to a density meter for slurry which is transported through a pipe, the density meter may include a frame; a pipe part; flexible pipe couplings arranged between the frame and either end of the pipe part for coupling the pipe part to the frame and to a feed pipe and a discharge pipe; a first accelerometer arranged on the pipe part for measuring the accelerations of the pipe part; an actuator arranged between the pipe part and the frame for imparting force on the pipe; a controller for controlling the actuator; and a computing means having a mathematical model to ultimately calculate the density of the slurry in the pipe part.

A device and a method for measuring and/or monitoring at least one process variable of a medium is provided. The device comprises a sensor unit with a mechanically vibrating unit, at least one reflection unit, a piezoelectric element which is attached to the membrane, and an electronic. The device is designed to excite the mechanically vibrating unit to mechanical vibrations using an excitation signal, to receive the mechanical vibrations of the vibrating unit and convert them into a first reception signal, to emit a transmission signal, and to receive a second reception signal. The electronic unit is designed to determine the at least one process variable of the medium based on the first and/or second reception signal.

An asphalt density estimation system includes a measurement device configured to output a measurement signal; a time synchronization unit configured to sample the measurement signal to obtain a sampled measurement signal and identify periodic sampling points of the sampled measurement signal across a plurality of periods. The system also includes a time synchronous averaging unit configured to construct a modified measurement signal in the time domain by: for at least one sampling point within the period, averaging a plurality of the periodic sampling points across periods to obtain an average periodic data point for the at least one sampling point, and constructing the modified measurement signal using the average periodic data point for the at least one sampling point. The system further includes a density calculation unit configured to determine asphalt density values based on the modified measurement signal; and a display unit configured to display the determined asphalt density values.