Abstract: A densitometer in the present disclosure comprises a measurement module that is calibrated to estimate sample fluid density with high accuracy and minimized sensitivity to temperature of tube and clamp components in the densitometer. The densitometer measures sample fluid density by vibrating the sample fluid and measuring the resonant frequency of the sample fluid, then estimating the sample fluid density based on this resonant frequency. The measurement module is calibrated specific to dissimilar tube and clamp materials. The tube and the clamp of the densitometer have materials are chosen to be cost-effective based on the specifications of the densitometer system and to have coefficients of thermal expansion (CTEs) which reduce temperature dependence of the resonant frequency of the sample fluid inside of the densitometer.

Abstract: A densitometer in the present disclosure comprises tension measuring devices that send tension measurements to a measurement module enabling the measurement module to estimate fluid density with increased accuracy. The densitometer measures sample fluid density by vibrating the sample fluid and measuring the resonant frequency of the sample fluid, then estimating the sample fluid density based on this resonant frequency. A set of tension measuring devices affixed to a tube of the densitometer measure external forces on the tube due to O-ring seals and other operational conditions. The sample fluid density estimate uses these tension measurements to take into account O-ring friction and other external forces applied to the densitometer to improve the accuracy of the calculated density.

Abstract: An apparatus, system, and method are disclosed herein. In one embodiment, the apparatus includes a plurality of valves. Each valve of the plurality of valves is associated with a respective production zone of a well. Each valve includes a valve body having a passage and an inflow fluid input through which a formation fluid from the respective production zone associated with the valve is to enter the passage of the valve body. Each valve further includes a sensor located within the valve body to detect a density of the formation fluid. The apparatus further includes a processor programmed to determine a fraction of a subject fluid in the formation fluid based on the density of the formation fluid and a density of the subject fluid.

Abstract: In one embodiment, the apparatus includes a production tubing for carrying fluids from a producing zone to a surface, and a three-way valve coupled to the production tubing, the three-way valve including an inlet from the production tubing, an outlet to the production tubing, and an inlet from the borehole surrounding the three-way valve. The apparatus further includes a resonant tube densitometer disposed in the outlet to the production tubing, the resonant tube densitometer configured to measure the density of the fluids. A flow meter is disposed in the outlet to the production tubing, the flow meter configured to measure volumetric flow of the fluids.

Abstract: A thermal sensor module, comprising: a housing, wherein the housing comprises a first end and a second end, wherein the housing is hollow and configured to allow a fluid to flow into the housing through the first end and exit through the second end; a heat source, wherein the heat source is disposed at a central axis of the housing and traverses at least partially through the housing; and a temperature sensor, wherein the temperature sensor is positioned in the housing to measure temperature of the fluid flowing in the housing.

Abstract: A distributed acoustic system (DAS) method and system. The system may comprise an interrogator and an umbilical line comprising a first fiber optic cable and a second fiber optic cable attached at one end to the interrogator. The DAS may further include a downhole fiber attached to the umbilical line at the end opposite the interrogator and a light source disposed in the interrogator that is configured to emit a plurality of coherent light frequencies into the umbilical line and the downhole fiber. The method may include generating interferometric signals of the plurality of frequencies of backscattered light that have been received by the photo detector assembly and processing the interferometric signals with an information handling system.

Abstract: A method and system can include positioning an optical waveguide along a wellbore, and launching one or more optical signals into the waveguide at one or more optical signal frequencies and during one or more time periods, thereby resulting in one or more backscattered signals being received by the receiver, which produces a trace for each of the one of more backscattered signals. Changing an environmental condition in the wellbore, generating additional backscattered light signals at one or more frequencies after the change. Comparing the traces generated before the condition change to those generated after the change, identifying a before trace and an after trace that are substantially equal to each other and identifying a frequency difference between these traces. The frequency difference can be used to determine the amount of change in the environmental condition that occurred when the environmental change event happened.

Abstract: The subject technology relates to distributed sensing interrogation using single-mode fiber for multi-mode fiber interrogation. The subject technology includes deploying a distributed sensing tool into a wellbore, and logging the wellbore using the distributed sensing tool. The distributed sensing tool includes an optical amplifier and an optical filter coupled to a single-mode optical fiber and a multi-mode optical fiber. The optical amplifier is coupled to a single-mode circulator for amplifying a single-mode optical signal, and the optical filter is coupled to the optical amplifier for filtering the amplified single-mode optical signal. The single-mode circulator is coupleable to an interrogator for routing the single-mode optical signal to the multi-mode optical fiber and routing a reflective optical signal from the multi-mode optical fiber to the interrogator.

Abstract: Aspects of the subject technology relate to systems and methods for determining positions of cementing plugs during a cementing process. Systems and methods are provided for determining a length of an optical fiber line deployed into a wellbore for a cementing process, measuring signal intensity data as a function of distance from the optical fiber line, the optical fiber line being attached to a lower cementing plug and an upper cementing plug, the upper cementing plug being attached to the optical fiber line by an attenuation assembly, generating signal intensity profiles based on the signal intensity data as a function of a round trip delay of a light signal in the optical fiber line, and determining positions of the lower cementing plug and the upper cementing plug based on the signal intensity profiles of the optical fiber line.

Abstract: A method and system can include positioning an optical waveguide along a wellbore, and launching one or more optical signals into the waveguide at one or more optical signal frequencies and during one or more time periods, thereby resulting in one or more backscattered signals being received by the receiver, which produces a trace for each of the one of more backscattered signals. Changing an environmental condition in the wellbore, generating additional backscattered light signals at one or more frequencies after the change. Comparing the traces generated before the condition change to those generated after the change, identifying a before trace and an after trace that are substantially equal to each other and identifying a frequency difference between these traces. The frequency difference can be used to determine the amount of change in the environmental condition that occurred when the environmental change event happened.

Abstract: An apparatus comprises a distributed acoustic sensing (DAS) optical fiber, a DAS interrogator coupled to the DAS optical fiber, and a connector. The connector couples the DAS interrogator, a first digitizer, and a second digitizer, wherein the first digitizer is to generate a first digitized DAS signal based on an analog DAS signal from the DAS interrogator, and the second digitizer is to generate a second digitized DAS signal based on the analog DAS signal. The apparatus also comprises one or more processors and a machine-readable medium having program code executable to cause the apparatus to simultaneously generate a first set of values that correlate with a first physical property based on the first digitized DAS signal and generating a second set of values that correlate with a second physical property based on the second digitized DAS signal.

Abstract: A distributed acoustic system (DAS) with an interrogator, an umbilical line attached at one end to the interrogator, and a downhole fiber attached to the umbilical line at the end opposite the interrogator. A method for optimizing a sampling frequency may begin with identifying a length of a fiber optic cable connected to an interrogator, identifying one or more regions on the fiber optic cable in which a backscatter is received, and optimizing a sampling frequency of a distributed acoustic system (DAS) by identifying a minimum time interval that is between an emission of a light pulse such that at no point in time the backscatter arrives back at the interrogator that corresponds to more than one spatial location along a sensing portion of the fiber optic cable.

Abstract: Technologies for propagating optical information through an optical waveguide in a downhole environment are provided. An example method can include generating a light signal via a light-emitting device at a first location on a wellbore environment; propagating the light signal through an optical waveguide on an inner surface of a wellbore tool, the optical waveguide including a first layer of low refractive-index material, a second layer of high refractive-index material applied to a first surface of the first layer, and a third layer of low refractive-index material applied to a second surface of the second layer; and receiving, by a detector at a second location on the wellbore environment, the light signal via the optical waveguide on the inner surface of the wellbore tool.

Abstract: A property of a downhole fluid, for example, a chemical species or ion concentration, may be accurately determined and logged based on measurements received from an optical detector where the optical detector is fed information or signals from an optical system coupled to one or more electrochemical probes calibrated for one or more properties of a fluid. The one or more electrochemical probes provide a potential to the optical system based, at least in part, on exposure to the downhole fluid. The optical system receives an optical signal from a light source that is transmitted via a transmission line, such as a fiber optic cable. Downhole information from the optical system is transmitted to the surface via the same or another transmission line. Thus, the signals are in the optical domain rather than the electrical domain. Multiple properties may be measured simultaneously using the same transmission line.

Abstract: A system and a method for performing a borehole operation, wherein the system may comprise a coiled tubing string and a fiber optic cable disposed in the coiled tubing string and wherein the fiber optic cable is strain-coupled to the coiled tubing string. A method of performing a borehole operation may comprise disposing a coiled tubing string into a borehole and wherein a fiber optic cable is strain-coupled to the coiled tubing string, and measuring at least one property of the borehole with the fiber optic cable.

Abstract: A distributed acoustic system may comprise an interrogator which includes a single photon detector, an umbilical line comprising a first fiber optic cable and a second fiber optic cable attached at one end to the interrogator, and a downhole fiber attached to the umbilical line at the end opposite the interrogator. A method for optimizing a sampling frequency may comprise identifying a length of a fiber optic cable connected to an interrogator, identifying one or more regions on the fiber optic cable in which a backscatter is received, and optimizing a sampling frequency of a distributed acoustic system by identifying a minimum time interval that is between an emission of a light pulse such that at no point in time the backscatter arrives back at the interrogator that corresponds to more than one spatial location along a sensing portion of the fiber optic cable.

Abstract: Disclosed are methods and apparatus for using an audible signal to monitor conditions at a downhole location in a well through use of a well cable containing a fiber optic, which may be either a slickline or a wireline fiber-optic cable, and providing an audible signal which varies in response to the monitored condition. The condition monitored can be strain in the fiber optic well cable, which can be sensed in one or more locations in the fiber optic well cable, in many examples through use of a sensor such as a Bragg grating associated with or formed in an optical fiber within the well cable. In some examples, a temperature measurement may be used to compensate for temperature effects impacting the strain measurement.

Abstract: A system, method, and device for determining volume concentration with diffraction of electromagnetic radiation. A device for determining a volume concentration of a fluid in a sample comprises a transducer, a transmitter, a detector, and a processor. The transducer generates a standing acoustic wave through the sample. The transmitter emits electromagnetic (EM) radiation into the sample such that the EM radiation is diffracted by the sample. The detector is responsive to the diffracted EM radiation and generates a signal indicative of a wavelength of an acoustic wave corresponding to the standing acoustic wave. The processor analyzes the signal to determine the volume concentration of the fluid in the sample.

Abstract: The water cut of a fluid used or produced in conjunction with wellbore operations may be measured or otherwise estimated using an ion selective fiber sensor. For example, a method may include flowing a fluid comprising an aqueous phase and an oleaginous phase through a sensor; contacting an ion selective fiber positioned in the sensor with the fluid, wherein the ion selective fiber has an intrinsic time constant (?0) associated with an intrinsic color change of the ion selective fiber in response to contact with the aqueous phase; measuring a color change of the ion selective fiber in response to contact with the fluid as a function of time; deriving an effective time constant (?eff) for the color change of the ion selective fiber in response to contact with the fluid; and calculating a water cut (Y) in the fluid based on Y= Y = ? 0 ? eff .

Abstract: Technologies for propagating optical information through an optical waveguide in a downhole environment are provided. An example method can include generating a light signal via a light-emitting device at a first location on a wellbore environment; propagating the light signal through an optical waveguide on an inner surface of a wellbore tool, the optical waveguide including a first layer of low refractive-index material, a second layer of high refractive-index material applied to a first surface of the first layer, and a third layer of low refractive-index material applied to a second surface of the second layer; and receiving, by a detector at a second location on the wellbore environment, the light signal via the optical waveguide on the inner surface of the wellbore tool.