摘要:
A method and apparatus for analyzing a deposited layer on the inner surface of a fluid container wall having inner and outer surfaces are disclosed. One embodiment of the method comprises (a) transmitting an acoustic signal from a transmitter at a first distance from the outer surface of the wall; (b) receiving a first received signal A, comprising a reflection from the wall outer surface; (c) receiving a second received signal B, comprising a reflection from the wall inner surface; (d) receiving a third received signal C from the wall inner surface; (e) calculating a coefficient Rwp from A, B and C, and (f) calculating a coefficient Rpd from A, B and Rwp, and calculating the acoustic impedance of the deposited layer Zd from Rwp, Rpd, and Zw, where Zw is the acoustic impedance of the material between the transmitter and the wall outer surface. A preferred embodiment of the apparatus comprises a piezoelectric or ferroelectric transducer having front and back faces; a backing member acoustically coupled to said transducer back face and impedance-matched to said transducer element, said backing member having proximal and remote faces; and a delay material disposed between said transducer front face and the wall outer surface.
摘要:
A system for monitoring the presence of deposits or buildup on the inside wall of a fluid-containing pipe comprises a pair of acoustic transmitters outside of the pipe and spaced apart along the length of the pipe and capable of transmitting an acoustic signal into the pipe wall, a pair of acoustic receivers outside of the pipe and spaced apart along the length of the pipe and capable of receiving an acoustic signal from the pipe wall, and a power source for causing the transmitters to transmit a signal. A method for monitoring the presence of deposits or buildup on the inside wall of a fluid-containing pipe, comprises (a) providing first and second acoustic transmitters outside of the pipe and spaced apart along the length of the pipe and capable of transmitting an acoustic signal into the pipe wall, (b) providing first and second acoustic receivers outside of the pipe and spaced apart along the length of the pipe and capable of receiving an acoustic signal from the pipe wall, (c) transmitting a first signal from the first transmitter, (d) measuring the amplitude of the first signal received at the first and second receivers as A11 and A12, respectively, (e) transmitting a second signal from the second transmitter, (f) measuring the amplitude of the second signal received at the first and second receivers as A21 and A22, respectively, and (g) calculating the attenuation of the signal over the length of pipe using the values of A11, A12, A21 and A22.
摘要:
A method and apparatus for analyzing a deposited layer on the inner surface of a fluid container wall having inner and outer surfaces are disclosed. One embodiment of the method comprises (a) transmitting an acoustic signal from a transmitter at a first distance from the outer surface of the wall; (b) receiving a first received signal A, comprising a reflection from the wall outer surface; (c) receiving a second received signal B, comprising a reflection from the wall inner surface; (d) receiving a third received signal C from the wall inner surface; (e) calculating a coefficient Rwp from A, B and C, and (f) calculating a coefficient Rpd from A, B and Rwp, and calculating the acoustic impedance of the deposited layer Zd from Rwp, Rpd, and Zw, where Zw is the acoustic impedance of the material between the transmitter and the wall outer surface. A preferred embodiment of the apparatus comprises a piezoelectric or ferroelectric transducer having front and back faces; a backing member acoustically coupled to said transducer back face and impedance-matched to said transducer element, said backing member having proximal and remote faces; and a delay material disposed between said transducer front face and the wall outer surface.
摘要:
A method for monitoring and measuring the buildup of deposits on the inner surface of a pipeline containing flowing fluid comprises (a) transmitting a first acoustic signal into the pipeline through the pipeline wall, (b) receiving echoes of the transmitted signal, and (c) determining from the received echoes how far from the pipeline inner surface the interface between the deposits and the flowing fluid lies. An alternative method for monitoring and measuring the buildup of deposits on the inner surface of a pipeline containing flowing fluid comprises (a) transmitting a first acoustic signal into the pipeline through the pipeline wall, (b) receiving echoes of the signal, and (c) using the Doppler frequency shift of the received echoes to determine how far from the pipeline inner surface the interface between the deposits and the flowing fluid lies. An apparatus for monitoring and measuring the buildup of deposits on the inner surface of a pipeline containing flowing fluid, comprises a first transmitter in acoustic communication with the pipeline wall and generating a transmitted signal, a first receiver in acoustic communication with the pipeline wall generating received echo signal from a received signal comprising the reflection of the transmitted signal off the flowing fluid, and a microprocessor for determining from the received echo signal how far from the pipeline inner surface the interface between the deposits and the flowing fluid lies.
摘要:
A process and apparatus for treating a wellbore, comprising subjecting a substantially same portion of the wellbore to vibratory waves produced by a plurality of vibratory wave generators. The vibratory waves may have about the same frequency or a plurality of frequencies, and the frequencies may partially overlap, not overlap, or be modulated across a range. Additionally, the frequencies may be modulated in an oval, hoop, and flexural modes. The vibratory waves may be produced by firing the vibratory wave generators simultaneously or in sequence. Combinations of a vibrating pipe, piston pulser, or valve may be used as vibratory wave generators. In a preferred embodiment, the thickness and change of thickness of a mudcake on the interior surface of a wellbore are measured to evaluate the effectiveness of the wellbore treatment.
摘要:
A method and apparatus for in-situ characterization of downhole fluids in a wellbore using ultrasonic acoustic signals. Measurements of the speed of sound, attenuation of the signal, and acoustic back-scattering are used to provide qualitative and quantitative data as to the composition, nature of solid particulates, compressibility, bubble point, and the oil/water ratio of the fluid. The tool generally comprises three sets of acoustic transducers mounted perpendicular to the direction of the flow. These transducers are capable of operating at different frequencies so that the spectrum of the acoustic signal can be optimized. The apparatus is capable of operating downhole to provide real time information as to conditions in the well.
摘要:
A method and apparatus for in-situ characterization of downhole fluids in a wellbore using ultrasonic acoustic signals. Measurements of the speed of sound, attenuation of the signal, and acoustic back-scattering are used to provide qualitative and quantitative data as to the composition, nature of solid particulates, compressibility, bubble point, and the oil/water ratio of the fluid. The tool generally comprises three sets of acoustic transducers mounted perpendicular to the direction of the flow. These transducers are capable of operating at different frequencies so that the spectrum of the acoustic signal can be optimized. The apparatus is capable of operating downhole to provide real time information as to conditions in the well.
摘要:
A system and method for determining blockage in a wellbore containing fluid and/or in a formation adjacent the wellbore, according to which energy is generated in the fluid and variables associated with the energy are measured.
摘要:
A method for generating acoustic waves, the method having the steps of: extending a tine from a support structure so that a proximal end of the tine is attached to the support structure and a distal end of the tine is uninhibited; positioning an oscillator so as to be supported by the support structure and to mechanically communicate with the tine; and oscillating the tine with the oscillator.
摘要:
There is disclosed herein a method and apparatus that use ultrasonic signals to measure rheological properties of a fluid flow such as, e.g., the consistency index K, the flow behavior index n′, the yield stress &tgr;0, or other parameters of any given model for shear rate dependent viscosity &eegr;. In one embodiment, the method includes: (a) transmitting an acoustic signal into the fluid flow; (b) receiving acoustic reflections from acoustic reflectors entrained in the fluid flow; (c) determining a Doppler shift of the acoustic reflections in a set of time windows corresponding to a set of desired sampling regions in the fluid flow; and (d) analyzing the Doppler shifts associated with the set of sampling regions to determine one or more rheological properties of the fluid flow. The frequency shift caused by motion of the fluid is proportional to the velocity of the fluid, and this allows the construction of a velocity profile of the fluid flow stream. The velocity profile can be normalized and “matched” to one of a family of velocity profile templates, and the rheological properties identified by the curve that matches best. Alternatively, the shear rate as a function of shear stress can be calculated from the measurements, and these values may be used to find each of the parameters directly. In one embodiment, the apparatus includes a transmitter, a receiver, and an electronic module. The transmitter transmits an acoustic signal into the fluid flow. The receiver receives reflections of the acoustic signal from entrained acoustic reflection sources in the fluid flow. The electronic module is coupled to the transmitter and receiver, and is configured to provide a pulsed high frequency signal to the transmitter and, responsive to the signal from the receiver, to determine a velocity vs. position profile of the fluid flow.