Abstract: An assembly for use in a wellbore can include a plurality of sensors positioned external to a casing string. The plurality of sensors can be positioned for detecting an amount of a hydrocarbon that is present in a fluid in the wellbore and a pH of the fluid in the wellbore. The plurality of sensors can be positioned for wirelessly transmitting signals representing the amount of the hydrocarbon that is present in the fluid and the pH of the fluid to a receiving device.

Abstract: Embodiments of the present disclosure include a method including receiving first impact data. The method includes receiving second impact data. The method includes applying a first filter to both the first impact data and the second impact data. The method includes applying a second filter to both the first impact data and the second impact data. Filtering includes time and frequency based discriminating filter to isolate specific signatures that representatively indicate impact signatures generated by the sand on the interrogator. The method includes comparing the first impact data and the second impact data for corresponding signatures. The method includes identifying a corresponding signature in both the first impact data and the second impact data. The method includes determining the corresponding signature meets a threshold criterion. The method includes determining one or more particulate properties based at least in part on the corresponding peak.

Abstract: A communication system that is positionable in a wellbore can include a first transceiver positioned externally to a casing string. The first transceiver can be operable to detect a presence or an absence of a surface wave; determine a location of a fluid in the wellbore based on the presence or the absence of the surface wave; and transmit data indicative of the location to a second transceiver. The surface wave can include an electromagnetic wave that has a magnetic field or an electric field that is non-transverse to a direction of propagation of the surface wave. The communication system can also include the second transceiver, which can be positioned externally the casing string and operable to receive the data.

Abstract: An assembly for use in a wellbore can include a plurality of sensors positioned external to a casing string. The plurality of sensors can be positioned for detecting an amount of a hydrocarbon that is present in a fluid in the wellbore and a pH of the fluid in the wellbore. The plurality of sensors can be positioned for wirelessly transmitting signals representing the amount of the hydrocarbon that is present in the fluid and the pH of the fluid to a receiving device.

Abstract: An assembly for use in a wellbore can include a plurality of sensors positioned external to a casing string. The plurality of sensors can be positioned for detecting an amount of a hydrocarbon that is present in a fluid in the wellbore and a pH of the fluid in the wellbore. The plurality of sensors can be positioned for wirelessly transmitting signals representing the amount of the hydrocarbon that is present in the fluid and the pH of the fluid to a receiving device.

Abstract: Embodiments of the present disclosure include a method including receiving first impact data. The method includes receiving second impact data. The method includes applying a first filter to both the first impact data and the second impact data. The method includes applying a second filter to both the first impact data and the second impact data. Filtering includes time and frequency based discriminating filter to isolate specific signatures that representatively indicate impact signatures generated by the sand on the interrogator. The method includes comparing the first impact data and the second impact data for corresponding signatures. The method includes identifying a corresponding signature in both the first impact data and the second impact data. The method includes determining the corresponding signature meets a threshold criterion. The method includes determining one or more particulate properties based at least in part on the corresponding peak.

Abstract: An apparatus and method may operate to mount one or more communication assemblies relative to the exterior of a casing being placed in a borehole. Two communication assemblies can be placed in longitudinally spaced relation to one another along the casing, wherein each communication assembly is configured to obtain excitation responses from electrodes of a fluid sensing component, where the excitation responses vary based on properties of fluids in one or more regions of the annulus surrounding the casing. Additional apparatus, systems, and methods are disclosed.

Abstract: A communication system that is positionable in a wellbore can include a first transceiver positioned externally to a casing string. The first transceiver can be operable to detect a presence or an absence of a surface wave; determine a location of a fluid in the wellbore based on the presence or the absence of the surface wave; and transmit data indicative of the location to a second transceiver. The surface wave can include an electromagnetic wave that has a magnetic field or an electric field that is non-transverse to a direction of propagation of the surface wave. The communication system can also include the second transceiver, which can be positioned externally the casing string and operable to receive the data.

Abstract: A method includes deploying an object inside a casing installed in a well, and transmitting a pulse conveyed by fluid in the casing. The method also includes receiving a reflection in response to the pulse, and analyzing a travel time for the reflection determine a position of the object in the well. A related system includes a casing installed in a well, and a pulse transmitter in fluid communication with the casing and configured to transmit pulses via fluid in the casing. The system also includes a receiver in fluid communication with the casing and configured to receive pulse reflections, and a processor in communication with the receiver. The processor analyzes a travel time for at least one pulse reflection to determine a position of an object in the well.

Abstract: An assembly for use in a wellbore can include a plurality of sensors positioned external to a casing string. The plurality of sensors can be positioned for detecting an amount of a hydrocarbon that is present in a fluid in the wellbore and a pH of the fluid in the wellbore. The plurality of sensors can be positioned for wirelessly transmitting signals representing the amount of the hydrocarbon that is present in the fluid and the pH of the fluid to a receiving device.

Abstract: One embodiment includes a method comprising receiving an acoustic signal that is propagated along a drill string. The method also includes correlating the acoustic signal to a first stored acoustic signal representing a first symbol, wherein the first stored acoustic signal is acquired from a propagation along the drill string in an approximately noise free environment.

Abstract: An embodiment includes an apparatus for wireless communications in a drilling operations environment. In an embodiment, the apparatus includes an instrument hub that is inline with drill pipe of a drill string. The instrument hub includes a sensor to receive downhole communications from downhole. The instrument hub also includes a transmitter to wireless transmit data representative of the downhole communications to a data processor unit.

Abstract: The resonant frequency of an example transducer can be adjusted by changing the effective mass of a backing mass using a tuning module. The tuning module includes a electrical source, a switch, and an electromagnetic coil connected in series as an electrical circuit. The electromagnetic coil is mechanically attached to the backing mass, and is disposed within a reservoir of a magneto-rheological fluid enclosed within a casing. When the switch is closed, the electrical source applies a voltage and current to the electromagnetic coil, and induces a localized magnetic field within the magneto-rheological fluid. In response to this localized magnetic field, the magneto-rheological fluid increases in viscosity, assumes properties comparable to a viscoelastic solid, and become affixed to the electromagnetic coil. As the electromagnetic coil is mechanically attached to the backing mass, the solidified magneto-rheological fluid increases the effective mass of the backing mass.

Abstract: One embodiment includes a method comprising receiving an acoustic signal that is propagated along a drill string. The method also includes correlating the acoustic signal to a first stored acoustic signal representing a first symbol, wherein the first stored acoustic signal is acquired from a propagation along the drill string in an approximately noise free environment.

Abstract: The resonant frequency of an example transducer can be adjusted by changing the effective mass of a backing mass using a tuning module. The tuning module includes a electrical source, a switch, and an electromagnetic coil connected in series as an electrical circuit. The electromagnetic coil is mechanically attached to the backing mass, and is disposed within a reservoir of a magneto-rheological fluid enclosed within a casing. When the switch is closed, the electrical source applies a voltage and current to the electromagnetic coil, and induces a localized magnetic field within the magneto-rheological fluid. In response to this localized magnetic field, the magneto-rheological fluid increases in viscosity, assumes properties comparable to a viscoelastic solid, and become affixed to the electromagnetic coil. As the electromagnetic coil is mechanically attached to the backing mass, the solidified magneto-rheological fluid increases the effective mass of the backing mass.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to program a first acoustic repeater to transmit information at a first operating frequency; to couple the first acoustic repeater circumferentially around a coiled tubing portion, an inner diameter of the first acoustic repeater being about equal to an outer diameter of the coiled tubing portion; to program a second acoustic repeater to receive information transmitted by the first acoustic repeater; and to receive sensor information transmitted at the first operating frequency by the first acoustic repeater and relayed by the second acoustic repeater, the second acoustic repeater being coupled to the coiled tubing portion uphole from the first acoustic repeater. Additional apparatus, systems, and methods are disclosed.

Abstract: An apparatus and method may operate to mount one or more communication assemblies relative to the exterior of a casing being placed in a borehole. Two communication assemblies can be placed in longitudinally spaced relation to one another along the casing, wherein each communication assembly is configured to obtain excitation responses from electrodes of a fluid sensing component, where the excitation responses vary based on properties of fluids in one or more regions of the annulus surrounding the casing. Additional apparatus, systems, and methods are disclosed.

Abstract: An embodiment includes a method comprising transmitting and receiving an acoustic signal that is modulated along a jointed tubing. The acoustic signal may be transmitted in multiple passbands of the jointed tubing and may be modulated differently in different passbands. A swept frequency signal may be used to determine transmission characteristics of the jointed tubing and to select the multiple passbands. Additional embodiments are disclosed.

Abstract: An embodiment includes an apparatus for wireless communications in a drilling operations environment. In an embodiment, the apparatus includes an instrument hub that is inline with drill pipe of a drill string. The instrument hub includes a sensor to receive downhole communications from downhole. The instrument hub also includes a transmitter to wireless transmit data representative of the downhole communications to a data processor unit.

Abstract: An apparatus for wireless communications in a drilling operations environment can include an instrument hub that is inline with drill pipe of a drill string. The instrument hub includes a sensor to receive downhole communications from downhole. The instrument hub also includes a transmitter to wireless transmit data representative of the downhole communications to a data processor unit.