Abstract:
Pairs of acoustic transducers positioned at different radial distances in a conduit are used to measure travel times of acoustic signals in opposite directions and inclined to the direction of a fluid flow in the borehole. These contrapropagation measurements are used to estimate fluid velocity and volumetric flow rates of the fluid components in the conduit.
Abstract:
A device and related method for conducting a wellbore operation controls a tool by using at least one pressure estimated at a contact between a reaction surface and a contact face associated with the tool. The device may include a contact face and a sensor associated with the contact face. The sensor may be configured to estimate a pressure applied to the contact face.
Abstract:
An apparatus for estimating a property of a fluid downhole, is provided an includes: an optical fiber that receives light emitted from a light source and including an unclad portion adapted for contacting the fluid; a photodetector for receiving optical signals from the portion; and a spectrometer for obtaining an evanescent spectrum of the fluid from the portion. A method and a system are included.
Abstract:
In one aspect, an apparatus for use in a wellbore is provided that may include: a tool configured to be conveyed into the wellbore by a conveying member; and an electro-active polymer device (“EAP device”) configured to connect the tool to the conveying member when the EAP device is in a first mode or position and disconnect the tool from the conveying member when the EAP device is in a second mode or position. In another aspect, a method for releasing a tool in a wellbore is provided which includes: releasably connecting an EAP device to a conveying member and the tool; conveying the tool in the wellbore with the conveying member; and electrically activating the EAP device to release the tool from the conveying member in the wellbore.
Abstract:
A gamma ray detector uses a scintillation detector having a response that matches a response characteristic of a photodiode. The detector may be used to measure natural gamma rays and/or gamma rays produced by interaction of neutrons from a neutron source with the earth formation.
Abstract:
A photodiode whose long-wavelength cutoff is in the short-wavelength range (preferably, between ultraviolet and yellowish-green) having reduced temperature sensitivity is used in downhole applications. It may be matched with scintillation devices having an output matched to the response curve of the photodiode for use with nuclear logging devices. The photodiode may also be used in gyroscopes in which light from an LED matched to the photodiode is reflected from a spinning mass.
Abstract:
A method and apparatus are provided for determining a property of a fluid downhole by using a tunable optical grating to collect a fluid's spectrum over a wavelength region of interest. A property of the fluid is estimated from spectra that are obtained from light that has interacted with the fluid and then been reflected off of the tunable optical grating onto a photodetector.
Abstract:
An instrument for measuring gravitational acceleration, the instrument including: a plurality of accelerometers disposed about a three-dimensional structure, the plurality of accelerometers providing output used for measuring the gravitational acceleration; wherein each accelerometer in the plurality is implemented by at least one of a micro-electromechanical system (MEMS) and a nano-electromechanical system (NEMS).
Abstract:
A method and apparatus are provided that assess reservoir compartmentalization by determining whether there are compositional differences such as whether the isotopic ratios of carbon (13C/12C) or of oxygen (17O/18O) are the same or different in various parts of the reservoir. A quartz enhanced photoacoustic spectrometer is provided for analysis of reservoir samples taken in various parts of the reservoir for comparison of geochemical composition to estimate reservoir compartmentalization.
Abstract:
An instrument for use in a borehole, the instrument including a pressure tuned light source disposed in a housing adapted for insertion into the borehole.