231results about "Fluid pressure measurement by acoustic means" patented technology

The invention discloses a non-intrusive pipeline real-time monitoring, prewarning and fault locating system, and belongs to the technical field of pipeline system temperature and pressure monitoring, and pipeline system fault diagnosis. The method adopted by the invention comprises the following three aspects: temperature and pressure real-time monitoring, prewarning, and fault locating; the pressure monitoring and the temperature monitoring adopt non-intrusive measuring methods, the pressure is monitored by adopting an ultrasonic non-invasive measuring method, the temperature is monitored by adopting a traditional temperature sensor non-invasive measuring method, and sensors for pressure monitoring and temperature monitoring are mounted on the outer wall of a pipeline; a design database is used for prewarning a fault signal; and a negative-pressure wave leak detection method is adopted for locating a fault in a pipeline system.

A predetermined condition in a fluid-filled wellbore system can be detected by generating at least one sound in the wellbore system in response to the condition, such that a detectable change is created in some characteristic of the emitted sound, and detecting the at least one sound and the change, the detection being indicative that the predetermined condition has occurred. Equipment for facilitating detection of the condition can include a trigger operable in response to the condition; a generator operable to emit sound in the borehole and to create a detectable change in some characteristic of the emitted sound in response to the trigger; and at least one sensor operable to monitor the sound and detect the change, the detection being indicative that the predetermined condition has occurred. It is also possible to estimate a value of a property of a fluid-filled wellbore system. This can be accomplished by recording data including at least one of pressure and rate of flow at one or more locations in the wellbore system, and then estimating the value of the property by employing a model for predicting at least one of pressure and rate of flow dependent upon parameters detailing at least one of wellbore system geometry, viscoacoustic properties of the fluid and entrained solids contained in the wellbore system, locations of boundaries and entrained solids, and characteristics and locations of disturbances to pressure and flow in the wellbore system, in order to determine a best prediction of some attribute of the recorded data.

A sensor assembly for monitoring physical parameters in a given environment, such as in a tire or wheel assembly, includes an improved interface between sensor components. The sensor assembly includes a piezoelectric substrate on which resonator elements, such as surface acoustic wave (SAW) resonators are provided. The resonators are configured to produce electrical output at predetermined resonator frequency ranges that can be monitored to determined such information as pressure and temperature to which such devices are subjected. A projection is formed on a surface of the piezoelectric substrate, which selectively interfaces with a recessed surface area in a flexible lid casing component. The lid casing component and a rigid base casing component combine to form an enclosed package for the sensor assembly. An antenna may be coupled to the sensor assembly to facilitate receipt and / or transmission of communicated signals.

A method and apparatus for determining at least one characteristic of a fluid flowing within a pipe is provided. The fluid flow may include one or more liquid component bodies and one or more gas component bodies, which bodies occupy a substantial cross-sectional area of the pipe when passing a location in the pipe. The method includes, and the apparatus includes elements operable to perform, the steps of: 1) transmitting a signal into the fluid flow at the location within the pipe, and receiving the signal after it has traversed at least a portion of the fluid flow; 2) determining a time of flight of the signal traversing the fluid flow; 3) determining the presence of a liquid component body at the location in the pipe, using the determined time of flight; and 4) determining at least one characteristic of the fluid using fluid data generated if the liquid component body is present at the location.

The invention provides a micro-electro-mechanical device which includes a substrate, an electrode, and a diaphragm. The electrode includes plural vent holes. The diaphragm is disposed above and in parallel to the electrode, to form a capacitive sensor with the electrode. The diaphragm includes plural ribs protruding upward and / or downward from the diaphragm; the ribs are respectively disposed in correspondence to the plural vent holes and do not overlap nor contact the electrode. A method for making the micro-electro-mechanical device is also provided according to the present invention.

An apparatus and methods for acoustically analyzing a fluid sample and determining one or more properties of the sample are disclosed by the present invention. The apparatus comprises a chamber, a transmitter positioned within the chamber for transmitting an acoustic signal through the fluid, a reflector movably positioned within the fluid inside the chamber for reflecting the acoustic signal, and a receiver positioned within the chamber for detecting reflections of the acoustic signal. The methods employ the use of a transmitter, a reflector movably positioned within the fluid inside the chamber, and a receiver to characterize the fluid sample based on one or more of its acoustic properties.

An ultrasonic pulse / echo measurement arrangement includes an ultrasonic transducer (12), which is mounted spatially fixed on an air spring cover plate (4). The arrangement further includes a fixedly mounted reference reflector (14), a target reflector (16) mounted on a roll-off piston (8) or on the bumper (18) as well as a transmitter / receiver evaluation electronic circuit (30). The running time as well as the amplitude of the reference signal is evaluated to precisely determine the pressure present in the interior space of the air spring. The ultrasonic transducer (12) has a λ / 4-adaptation layer (22), whose impedance does not correspond to the geometric mean of the impedances of the ultrasonic transducer (12) and the ambient air of the interior space (20) of the air spring, but rather, is a mismatch. The evaluation electronic circuit (30) can be calibrated at ambient pressure for the determination of the inner pressure of the air spring. Preferably, the pressure measuring method according to the invention is also used to determine the running-time dependent spring height in an air spring (2) of a motor vehicle.

Many sensors could be used in a passive wireless mode. These include RLC, acoustic wave and magneto-elastic sensors. These types of sensors are designed to exhibit a change in fundamental frequency when exposed to environmental factors such as temperature, pressure, or chemicals. An interrogation circuit can inductively couple to the sensor and measure the change in fundamental frequency. The change can be used to measure the environmental factor. Sensor sensitivity and inductive coupling efficiency can be competing design constraints. A driver, electrically connected to the sensor and inductively coupled to the interrogation circuit, can relax the constraints. The driver, however, can introduce noise into the sensor. The sensor can be shielded using physical and geometric techniques to reduce the noise.

Tactile sensors are disclosed that mimic the human fingertip and its touch receptors. The mechanical components are similar to a fingertip, with a rigid core surrounded by a weakly conductive fluid contained within an elastomeric skin. The deformable properties of the finger pad can be used as part of a transduction process. Multiple electrodes can be mounted on the surface of the rigid core and connected to impedance measuring circuitry within the core. External forces deform the fluid path around the electrodes, resulting in a distributed pattern of impedance changes containing information about those forces and the objects that applied them. Strategies are described for extracting features related to the mechanical inputs and using this information for reflexive grip control. Controlling grip force in a prosthetic having sensory feedback information is described. Pressure transducers can provide sensory feedback by measuring micro-vibrations due to sliding friction.

Downhole distributed pressure sensor arrays include sensor housings each comprising at least one pressure sensor in a pressure housing. Downhole pressure sensors include a housing, at least one pressure sensor in a pressure housing portion of the housing, and at least one isolation element positioned at an outer wall of the housing.

A MEMS pressure sensor for sensing the pressure in a sealed cavity of a MEMS device, comprises a resonant MEMS device having a pressure sensor resonator element which comprises an array of openings. The resonant frequency of the resonant MEMS device is a function of the pressure in the cavity, with resonant frequency increasing with pressure. Over the pressure range 0 to 0.1 kPa, the average change in frequency is at least 10−6 / Pa. The invention is based on the recognition that for fast oscillation, the elastic force causes the resonance frequency to shift. Therefore, it is possible to sense the pressure by a device with resonance frequency that is sensitive to the pressure.

To provide a double-ended tuning fork type piezoelectric resonator that includes: a piezoelectric element having two arm portions disposed in parallel, a first supporting portion that support one ends of each of the arm portions, a second supporting portion that support the other ends of each of the arm portions; and an exciting electrode formed on a surface of each of the arm portions, and has a structure suitable for being built into a pressure sensor as a pressure sensitive element.A double-ended tuning fork type piezoelectric resonator includes: a piezoelectric element 3 having two arm portions 4 disposed in parallel and apart from each other, and a first supporting portion 5 and a second supporting portion 6 that respectively support one ends and the other ends of each of the arm portions; and an exciting electrode 7 formed on a surface of each arm portion. In the resonator, an annular linking piece 8 is provided to link the first and the second supporting portions to dispose the two arm portions in an internal space of the annular linking piece.