摘要:
Methods for calibrating and making measurements using fiber optic sensors are disclosed using backscattered wavelengths and independent sensors. The disclosure sets outs methods applicable with fiber optic sensors either in a deployed in a loop and in a linear configuration and useful for measurements including temperature.
摘要:
Methods and apparatus for downhole analysis of formation fluids by isolating the fluids from the formation and/or borehole in a pressure and volume control unit that is integrated with a flowline of a fluid analysis module and determining fluid characteristics of the isolated fluids. Parameters of interest may be derived for formation fluids in a static state and undesirable formation fluids may be drained and replaced with formation fluids that are suitable for downhole characterization or surface sample extraction. Isolated formation fluids may be circulated in a loop of the flowline for phase behavior characterization. Real-time analysis of the fluids may be performed at or near downhole conditions.
摘要:
The apparatus of the present invention include an optical fiber with a Bragg grating formed along a portion of its core and a mechanical structure arranged adjacent to the Bragg grating for amplifying transverse strain on the fiber in the vicinity of the grating. In particular, the mechanical structure is designed to convert ambient pressure into transverse strain on the fiber in the vicinity of the grating. The methods of the invention include converting pressure into transverse strain on an optical fiber, amplifying the effect of pressure on the transverse strain, measuring pressure by determining the spacing between spectral locations related to peaks (or minimums) of light reflected from an optical grating subjected to transverse strain, and measuring the temperature of the grating by determining the locations of the spectral locations related to the peaks (or minimums) of light reflected from the grating. According to one embodiment, the mechanical structure includes a piston mounted in a transducer body through which the optical fiber passes.
摘要:
Example microfluidic methods and apparatus to perform in situ chemical detection are disclosed. A disclosed example downhole apparatus comprises a microfluidic chamber to introduce a microfluidic-scale drop of a reagent into a formation fluid to form a mixed fluid, a flowline to fluidly couple the formation fluid from a geologic formation to the microfluidic chamber, and a detector to measure a property of the mixed fluid, the property representative of a presence of a chemical in the formation fluid.
摘要:
A pressure transducer for high-pressure measurements comprising a housing and a piezoelectric resonator located in the housing, wherein the resonator comprises double rotation cut piezoelectric material configured or designed for vibrating in the fundamental tone of dual modes of the fast and slow thickness-shear vibrations.
摘要:
The present disclosure provides, among other things, apparatuses and methods for sensing subsurface data. One embodiment comprises borehole conveyance system tool, the borehole conveyance system tool comprising a conveyance, a sensor array disposed on the conveyance, and an acquisition electronics section disposed on the conveyance distal of the sensor array. One embodiment includes at least one downhole tension sensor to help indicate when a tool is stuck and what part of the tool is stuck.
摘要:
A downhole tool, configured to be suspended in a borehole traversing an earth formation, includes a downhole data acquisition system placed in the tool body and electrically connected to an electric power generator at the formation surface. The downhole data acquisition system includes a sensor for detecting local conditions in the borehole, and a transducer for transducing the voltage of an input signal from high to low or low to high. The transducer having a gallium nitride or silicon carbide based discrete semiconductor device.
摘要:
An apparatus for azimuth measurements comprises an elongated housing, a plurality of gyro sensors, each of the gyro sensors having an input axis for angular velocity measurements, spherical sensor holders arranged along the longitudinal direction of the housing, at least one motor for driving the sensor holders, a transmission mechanism for transmitting a rotation force from the motor to each of the sensor holders and a controller for controlling a rotation of the motor. Each of the sensor holders has one of the gyro sensors and is rotatable about a rotation axis so as to change the orientation of the input axis of the gyro sensor.
摘要:
Subterranean oilfield sensor systems and methods are provided. The subterranean oilfield sensor systems and methods facilitate downhole monitoring and high data transmission rates with power provided to at least one downhole device by a light source at the surface. In one embodiment, a system includes uphole light source, a downhole sensor, a photonic power converter at the downhole sensor, an optical fiber extending between the uphole light source and the photonic power converter, and downhole sensor electronics powered by the photonic power converter. The photonic power converter is contained in a high temperature resistant package. For example, the high temperature resistant package and photonic power converter may operate at temperatures of greater than approximately 100° C.
摘要:
A method for optically sampling characteristics of subsurface fluids within a wellhole using continuous, non-pulsed light transmitted downhole in optical fibers for both sampling and reference light channels for accurate attenuation compensation.