46 results about "Flexural waves" patented technology

Noninvasive method for determining the liquid level and density inside of a container having arbitrary dimension and shape. By generating a flexural acoustic wave in the container shell and measuring the phase difference of the detected flexural wave from that of the originally generated wave a small distance from the generated wave, while moving the generation and detection means through the liquid/vapor interface, this interface can be detected. Both the wave generation and wave detection may be achieved by transducers on the surface of the container. A change in the phase difference over the outer surface of the vessel signifies that a liquid/vapor interface has been crossed, while the magnitude of the phase difference can be related to fluid density immediately opposite the measurement position on the surface of the vessel.

An apparatus and method for determining fast and slow shear wave velocities and orientations in an anisotropic earth formation that reduces the error and ambiguity in calculating these parameters and eliminates the need for dipole receivers and multiple dipole sources. The apparatus generally includes a single dipole source capable of generating an acoustic signal within a borehole. The acoustic logging tool contains multiple levels of receivers. At each level, four receivers, which may be conventional pressure transducers, receive shear/flexural wave signals which propagate along the borehole earth formation. These receivers measure the pressure fields from the wave signals. A processing device, preferably a UNIX(TM) based computer, interpolates the measured pressure fields between any two adjacent receivers. The processing device performs cross-component decomposition on the pressure field to determine shear wave orientation and velocity. Using the shear wave orientation and velocity the processing device determines transit time anisotropy, energy anisotropy, and slowness anisotropy.

A system for exciting flexural waves on an optical fiber (102) is provided. The system includes a substrate (114, 118), an actuator (106), and a mechanical optical fiber coupling (104). The actuator is formed of an electromechanical transducer material. The actuator is mounted on the substrate. The mechanical optical fiber coupling (for example, an adhesive media) forms a secure mechanical connection between the actuator and the optical fiber. The mechanical optical fiber coupling is configured for communicating mechanical vibrations from the actuator to the optical fiber. However, it should be understood that the mechanical optical fiber coupling is exclusive of a tapered horn.

A door leaf includes a stiff, light structural part that maintains fed-in vibrational energy and, by flexural waves, propagates this energy in at least one active surface perpendicular to its thickness to distribute resonance mode vibration components over at least one surface, which has specified, preferred locations or sites within it for transducer devices, which are affixed on the structural part at one of the locations or sites to set the structural part into vibration and to allow it to resonate, thus creating an acoustic radiator that delivers an acoustic output signal when it vibrates in resonance, the front and/or the rear cover panel of the door leaf being part of the stiff, light structural component. The transducer(s) is/are situated between the cover panels. This arrangement provides a door with a loudspeaker function, which needs no extra volume compared to an ordinary door, and which is able to provide sound reliably and comprehensively to one or more rooms, which adjoin this door acting as a loudspeaker. Advantageously, additional loudspeakers or loudspeaker boxes are not required in a room that receives sound by this door with loudspeakers.

The invention is used in the field of oil field logging technology, mainly resolving the defect of existent earth stress detection technology which has not any one non-destructive examination method. Said invention is characterized by that it includes the following steps: making cross dipole array acoustic log data undergo the process of angle rotation treatment, then obtaining two main time sequences, on said basis extracting flexural wave dispersion curves of two principal directions, utilizing data of n frequency points on the flexural wave dispersion curves of two principal polarization directions to create n equalities according to two formulae, in which said formulae can be obtained by inversion of well mode wave acoustic elastic equation, in which n is greater than or equal to 6, and atilizing resolution of sain n equalities so as to can obtain maximum main stress SH and minimum main stress Sh of formation.

Cased-hole radial profiling of shear parameters from sonic measurements is disclosed. Example methods disclosed herein include determining a variation of a first shear modulus at a first radial position from a cased borehole in a formation based on a first weighted average of fractional variations of Stoneley wave velocities for different wavenumbers, the first weighted average based on first weights determined using a perturbation model including parameters to model the borehole casing, and determining variations of second and third shear moduli at respective second and third radial positions from the borehole based on second and third weighted averages of fractional variations of respective first and second flexural wave velocities for different wavenumbers, the first and second flexural wave velocities associated with respective first and second orthogonal borehole axial planes of the formation, the second and third weighted averages based on respective second and third weights determined using the perturbation model.

A robust tag. The robust tag may include a body section, at least one movable latching member disposed within the body section, at least one attachment structure receivable within the body and selectively engageable to the at least one latching member; and at least one responsive member disposed within the body and in cooperative arrangement with the at least one latching member. Upon the application of a signal to at least one drive position on the body section, the responsive member generates a flexural wave that induces a movement of the at least one latching member, so as to disengage the at least one latching member from the at least one attachment structure.

The present invention relates to a method for selecting sound source frequency, used in the cased-hole dipole shear wave acoustic log. Said invention is characterized by that said method includes the following steps: firstly, utilizing acoustic moveout curve to give out compressional wave velocity of said well: then utilizing velocity field equation under the column coordinate and boundarg connection condition under the condition of cased-hole and adopting three-dimensional velocity-stress finite difference method to numerically simulate the dipole acoustic all-wave wave field of oil-water well, then utilizing the quick and slow flexural waves obtained by means of numerical simulation under the condition of that the circumference of cased-hole has abonormal stress to make dispersion analysis; then utilizing the freguency of cross point of quick and slow flexural waves to define main frequency of sound source.

A door leaf includes a stiff, light structural part that maintains fed-in vibrational energy and, by flexural waves, propagates this energy in at least one active surface perpendicular to its thickness to distribute resonance mode vibration components over at least one surface, which has specified, preferred locations or sites within it for transducer devices, which are affixed on the structural part at one of the locations or sites to set the structural part into vibration and to allow it to resonate, thus creating an acoustic radiator that delivers an acoustic output signal when it vibrates in resonance, the front and/or the rear cover panel of the door leaf being part of the stiff, light structural component. The transducer(s) is/are situated between the cover panels. This arrangement provides a door with a loudspeaker function, which needs no extra volume compared to an ordinary door, and which is able to provide sound reliably and comprehensively to one or more rooms, which adjoin this door acting as a loudspeaker. Advantageously, additional loudspeakers or loudspeaker boxes are not required in a room that receives sound by this door with loudspeakers.

The invention discloses a method for measuring a material loss factor, which belongs to the measuring field of material damping characteristics. The method comprises the following steps of preparing two metal plates with same sizes and with same materials, laying one layer of materials to be measured on one metal plate so as to form a composite damping plate, measuring to obtain flexural wave propagation speeds of the composite damping plate and the metal plate at different impulse signal frequencies, calculating the Young modulus ratio e of a damping layer to a metal layer, measuring to obtain a loss factor beta of the composite damping plate structure, and then calculating to obtain the material loss factor eta of the damping layer. The method has the beneficial effects that the measurement of the structure loss factor and the flexural vibration wave speed is combined, so as to measure a self material loss factor of a multi-cavity damping material and overcome the defects on test of the multi-cavity damping material with soft texture and damping effect by other measuring methods, and therefore, the method has a certain engineering value and a broad application prospect.

The present invention provides a method and a device for determining a shear-wave attenuation factor in multi-pole array acoustic logging. The method comprises the following steps: acquiring multi-pole array acoustic logging data of a target stratum; according to the multi-pole array acoustic logging data of the target stratum, determining a corresponding flexural-wave attenuation factor; and determining the shear-wave attenuation factor at preset frequency by applying the flexural-wave attenuation factor, and evaluating the target stratum according to the shear-wave attenuation factor. By theadoption of the method provided by the invention, the shear-wave attenuation factor in multi-pole array acoustic logging can be effectively and accurately acquired, and then the evaluating accuracy of a target reservoir as well as the accuracy and the reliability of a reservoir exploration-development scheme can be effectively improved.

An acoustic glass breakage detector including a pulsating current-powered microphone and operable for generating pulsed signal data corresponding to sound waves detected thereby, a sample and hold circuit operable for converting the pulsed signal data into a voltage level signal and storing the voltage level signal, a sound frequency band pass amplifier operable for ascertaining whether the voltage level signal corresponds to an explosion-like sound typical of an initial glass-breakage sound, a flex wave band pass amplifier operable for ascertaining whether the voltage level signal corresponds to a flex wave typical of an initial glass-breakage sound, and circuitry operable, responsive to ascertaining that the voltage level signal corresponds to an explosion-like sound typical of an initial glass-breakage event and that the voltage level signal corresponds to a flex wave typical of an initial glass-breakage sound, for ascertaining that the pulsed signal data is indicative of a glass-breakage event.

A speaker cone is provided that contains a base portion, and the base portion has a front end and a rear end. The front end contains a plurality of discontinuities such that a first distance from a reference point on a longitudinal axis of the base portion to a first point on the front end is different than a second distance from the reference point to a second point on the front end. By creating the plurality of discontinuities in the front end of the base portion, the distortion or reduction in the amplitude of a flexural wave generated by the speaker cone is dramatically reduced.

Methods are disclosed for evaluating a material on a remote side of a partition separating first and second domains wherein flexural waves within the partition are received by spaced-apart ultrasonic receivers and processed to determine the velocity of the waves propagating into the second domain from a first receiver to a second receiver located more remote from the transmitter than the first receiver and whose separation from the first receiver is known. Comparison of a theoretical phase velocity with the measured phase velocity of the recorded waves allows determination as to whether the flexural wave is propagating through solid. This may be based on a measurable deviation between the two curves occurring at a critical frequency, which may be identified by a perturbation in a group velocity plot. Discrimination may also be based on the gradient of a straight line that best-fits the attention dispersion of the frequency spectrum.

The invention proposes an all-fiber acousto-optic frequency shifter and an all-fiber heterodyne measurement system applying the all-fiber acousto-optic frequency shifter, wherein the all-fiber acousto-optic frequency shifter includes a Bragg grating fiber, an aluminum cone and piezoelectric ceramics, the piezoelectric ceramics is fixedly adhered on the bottom plane of the aluminum cone, there is an angle in a range of 1.11 degrees to 1.15 degrees between the top plane and the bottom plane of the aluminum cone, and the top plane of the aluminum cone is vertically adhered on an end face of the Bragg grating fiber. A reflectance spectrum of the all-fiber acousto-optic frequency shifter changes with respect to a reflectance spectrum of an all-fiber acousto-optic frequency shifter under the action of an existing typical acoustic wave of a transverse flexural wave or an acoustic wave of a longitudinal wave, so that the all-fiber acousto-optic frequency shifter has higher reflectivity with the same driving power. The manufacturing cost of the all-fiber acousto-optic frequency shifter is reduced, while the power consumption is reduced, so that problems of a complicated structure, low coupling efficiency and a small modulation range and other problems of an existing all-fiber acousto-optic frequency shifter are solved.