An apparatus for determining a fluid's kinematic viscosity from ultrasonic energy that has passed through the fluid of unknown viscosity along an acoustic path of known length. A computer of the apparatus determines a characteristic frequency of a received electrical signal associated with the ultrasonic energy and measures the fluid's velocity of sound. The kinematic viscosity of the fluid is determined by the computer on a continuous basis based on the characteristic frequency and the sound velocity. A method for determining a fluid's kinematic viscosity.

A micropillar-enabled acoustic wave (PAW) viscometer including a quartz crystal microbalance (QCM) substrate; at least one micropillar having a first end and a second end, defining a height therebetween, the at least one micropillar disposed on to the QCM substrate at the first end and extending perpendicular to the QCM substrate; and a film disposed between the at least one micropillar and the QCM substrate.

A system features an acoustic sensor configured to mount on a wall of a mixing drum, sense an acoustic characteristic of a mixture of a slurry, including concrete, contained in a mixing drum when rotating, and provide acoustic sensor signaling containing information about the acoustic characteristic sensed; and a signal processor configured to receive the acoustic sensor signaling, and determine corresponding signaling containing information about a slump characteristic of the mixture of concrete contained in the mixing drum, based upon the signaling received.

A system and method for measuring one or more viscoelastic properties of a material under measurement is disclosed. The system includes an emitter-observer transducer pair separated by the material. A signal processing assembly is operable to (i) apply a plurality of excitation signals to the emitter transducer, wherein each of the excitation signals comprises a continuous-wave sinusoidal waveform, (ii) record a plurality of output signals at the observer transducer, wherein each of the output signals corresponds to one of the excitation signals, (iii) analyze the output signals to measure the sound speed of the material, and (iv) determine the viscoelastic properties of the material under measurement by optimizing the parameters of an infinite echo model. The system provides a non-destructive approach for in-situ measurement of viscoelastic material properties.

Methods, apparatus, and articles of manufacture to multi-purpose an acoustic emission sensor are disclosed. An example apparatus includes a collection engine to obtain a measurement from an acoustic emissions sensor coupled to a fluid flow control assembly, and obtain a state of the fluid flow control assembly. The example apparatus further includes a selector to adjust a gain of a pre-amplifier based on the state to adjust the measurement, and a condition identifier to identify a condition of the fluid flow control assembly based on the adjusted measurement.

A system for sensing the volume and/or viscosity of a slurry (e.g., like concrete) contained in a rotating container or drum, having a sensor and a signal processor. The sensor is configured to attach inside a rotating container or drum having a known geometry, sense angular positions of the sensor and also sense associated entry and exit points when the sensor enters and exits the slurry, including concrete, contained in the rotating container or drum, and provide signaling containing information about the angular positions and the associated entry and exit points. The signal processor receives the signaling, and determines corresponding signaling containing information about a volumetric amount, or a viscosity, or both, of the slurry in the rotating container or drum, based upon the signaling received.

A method for evaluating Dry Eye Disease (DED) in a human or animal subject is provided. Thread thinning dynamics of a tear sample of the subject are determined using an acoustically-driven microfluidic extensional rheometry instrument. At least one physical parameter value of the tear sample is calculated based at least in part on the determined thread thinning dynamics. DED is evaluated based at least in part on the at least one calculated physical parameter value of the tear sample. A device for evaluating Dry Eye Disease (DED) in a human or animal subject is also provided. The device includes an acoustically-driven microfluidic extensional rheometry instrument and a processing device configured to evaluate DED based at least in part on the calculated at least one physical parameter value of the tear sample.

Vibronic sensor and method of operation for monitoring the density and/or the viscosity of a medium in a container, comprising a mechanically oscillatable unit, a driving/receiving unit and an electronics unit, wherein the driving/receiving unit is embodied, using an electrical exciter signal, to excite the mechanically oscillatable unit to execute mechanical oscillations, and to receive the mechanical oscillations and to convert them into an electrical, received signal, wherein the electronics unit is embodied to produce the exciter signal such that a predeterminable phase shift is present between the exciter signal and received signal, wherein the electronics unit is embodied to set a first predeterminable phase shift and a second predeterminable phase shift, and to ascertain a first frequency and a second frequency corresponding to the predeterminable phase shifts, and to determine from the two frequencies the density and/or the viscosity of the medium using a first and/or second analytical formula.

A method for operating a measuring device determining a fluid quantity relating to fluid or fluid flow uses a measuring tube receiving the fluid or conducting the flow and oscillation transducers spaced along the tube. A first flight time is recorded, then an ultrasound signal excited by a first transducer, after travel on a propagation path including only components of the measuring device to a second transducer, is recorded at a second transducer. A second flight time is recorded, then an ultrasound signal excited by the second transducer, after travel on the propagation path to the first transducer, is recorded at the first transducer. Then fulfillment of a report condition depending on a difference between flight times is checked. Upon fulfillment, a report is output to a user or a report message is sent to an external device or a correction parameter for determining the fluid quantity is adapted.

The present disclosure relates to an apparatus for determining and/or monitoring a process variable of a medium in a containment, including an oscillatable unit with a membrane, three rods secured to the membrane and extending perpendicularly to a base area of the membrane, a housing, wherein the rods extend into the housing a driving/receiving unit disposed at an end region of the rods and configured to excite the oscillatable unit and transduce mechanical oscillations into a received signal, and an electronics unit configured to produce an exciter signal from the received signal and to ascertain the process variable at least from the received signal. At least one of the rods is secured to the membrane at a site on the base area where the second derivative of the deflection of the membrane from a rest position as a function of the site on the base area is essentially zero.