Abstract: A magnetic field sensor in the form of a multi-material optical fiber is described. The magnetic sensing optical fiber of the present disclosure can leverage optics and magnetostriction to sense an external magnetic field adjacent to the fiber. The magnetic sensing optical fiber can be customized to achieve various desired sensing sensitivities for various applications, including measuring while drilling and unconventional oil and gas applications. In one example, an optical fiber can include a cladding that can extend from a first end to a second end of the optical fiber. The optical fiber can further include an optical core within the cladding. The optical core can extend along the optical fiber between the first end and the second end. The optical fiber can also include a magnetostrictive element within the cladding. The magnetostrictive element can extend along the optical fiber between the first end and the second end.

Abstract: Techniques for abrasively blasting (e.g., grit blasting) components, such as ceramic or CMC components. In some examples, based on a comparison of component geometry to a target geometry, a blasting path over the surface of the component may be generated for a selected traverse speed. A computing device may control a blasting device to blast the component according to the generated blasting path with the selected traverse speed. In some examples, based on a comparison of a component geometry to a target geometry, a respective traverse speed for a blasting device relative the component for each section of a plurality of sections over a surface of the component may be generated. A computing device controls the blasting device to blast the component according to the respective traverse speeds relative over a surface of the component to remove material from the surface of the component.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one time-dependent acoustic data signal indicative of an acoustic signal generated by a thermal spray system performing a process possessing a plurality of process attributes, and a computing device including an acoustic data signal processing module configured to receive the at least one time-dependent acoustic data signal, and transform the at least one time-dependent acoustic data signal to a frequency-domain spectrum, wherein each process attribute of the plurality of process attributes is associated with at least one respective frequency band, and a correlation module configured to determine a process attribute of the plurality of process attributes by identifying at least one characteristic of the frequency-domain spectrum.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one time-dependent acoustic data signal indicative of an acoustic signal generated by a thermal spray system performing a process associated with a plurality of process attributes. The example system includes a computing device including an acoustic data signal module and a control module. The acoustic data signal processing module may transform the at least one time-dependent acoustic data signal to a frequency-domain spectrum. The control module may determine a process attribute of the plurality of process attributes that deviates from a predetermined operating range by identifying at least one characteristic of the frequency-domain spectrum, selecting at least one component of the thermal spray system based on the process attribute, and controlling the thermal spray system to adjust the process attribute toward the predetermined operating range by sending a control signal to the at least one component.

Abstract: A characteristic of a component having an engineered internal space can be analyzed by recording acoustic signals produced by fluid flow through the internal space at controlled flow rates, and determining one or more acoustic frequencies and acoustic intensities that are indicative of the characteristic of the component. A state and/or a source of the component can be predicted based on the results of such analysis.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one acoustic data signal indicative of an acoustic signal generated by a thermal spray system comprising a flowstream, a computing device, and an acoustic data signal processing module operable by the computing device to determine an ignition attribute of the thermal spray system by analyzing at least a pre-ignition window of the acoustic data signal received by the computing device.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one time-dependent acoustic data signal indicative of an acoustic signal generated by a thermal spray system performing a process associated with a plurality of process attributes. The example system includes a computing device including an acoustic data signal module and a control module. The acoustic data signal processing module may transform the at least one time-dependent acoustic data signal to a frequency-domain spectrum. The control module may determine a process attribute of the plurality of process attributes that deviates from a predetermined operating range by identifying at least one characteristic of the frequency-domain spectrum, selecting at least one component of the thermal spray system based on the process attribute, and controlling the thermal spray system to adjust the process attribute toward the predetermined operating range by sending a control signal to the at least one component.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one time-dependent acoustic data signal indicative of an acoustic signal generated by a thermal spray system performing a process possessing a plurality of process attributes, and a computing device including an acoustic data signal processing module configured to receive the at least one time-dependent acoustic data signal, and transform the at least one time-dependent acoustic data signal to a frequency-domain spectrum, wherein each process attribute of the plurality of process attributes is associated with at least one respective frequency band, and a correlation module configured to determine a process attribute of the plurality of process attributes by identifying at least one characteristic of the frequency-domain spectrum.

Abstract: An example system includes at least one acoustic sensor configured to generate at least one acoustic data signal indicative of an acoustic signal generated by a thermal spray system comprising a flowstream, a computing device, and an acoustic data signal processing module operable by the computing device to determine an ignition attribute of the thermal spray system by analyzing at least a pre-ignition window of the acoustic data signal received by the computing device.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A characteristic of a component having an engineered internal space can be analyzed by recording acoustic signals produced by fluid flow through the internal space at controlled flow rates, and determining one or more acoustic frequencies and acoustic intensities that are indicative of the characteristic of the component. A state and/or a source of the component can be predicted based on the results of such analysis.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: Open pore foams are coated with metal or metal alloys by electrolytic or electroless plating. The characteristics of the plating bath are adjusted to decrease the surface tension such that the plate bath composition can pass into the pores of the foam, preferably at least two and most preferably more than five pores in depth from the surface of the foam matrix. This can be accomplished by adding a surfactant, solvent or other constituent to reduce the surface tension of the plate bath. In addition, heat and pressure can be used to drive in the plate bath composition into the passage ways of connected open pores in the foam matrix. The net result is to plate the inside surfaces of the pores in the foam matrix, while maintaining the passageways through the foam. Pretreatment of the pore surfaces can be used to promote adhesion of the metal. Particularly advantageous results are achieved when the foam matrix is a ceramic foam.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: A random array of holes is created in an optical fiber by gas generated during fiber drawing. The gas forms bubbles which are drawn into long, microscopic holes. The gas is created by a gas generating material such as silicon nitride. Silicon nitride oxidizes to produce nitrogen oxides when heated. The gas generating material can alternatively be silicon carbide or other nitrides or carbides. The random holes can provide cladding for optical confinement when located around a fiber core. The random holes can also be present in the fiber core. The fibers can be made of silica. The present random hole fibers are particularly useful as pressure sensors since they experience a large wavelength dependant increase in optical loss when pressure or force is applied.

Abstract: Porous polymers are made by adding biologically active agent and growth substrates (e.g., yeast and sugar, preferably in the presence of water or other suitable fluid) to a polymer forming material, which may be a liquid. The yeast acts on the sugar, forming carbon dioxide gas bubbles. The material is then polymerized so that the gas bubbles create permanent pores within the polymeric material. The polymer can be an epoxy for example. The pores will contain residue of the yeast. Also, porous metals can be made by combining a metal powder with yeast, sugar, and water. The porous metal paste is then sintered. Porous ceramics and semiconductors can be made by combining the yeast and sugar with a ceramic forming liquid such as polysilazane. Polysilazane converts to silica when heated, which helps to bind the ceramic or semiconductor powder particles at a reduced temperature. Biological agents other than yeast (e.g. bacteria, enzymes), and growth substrates other than sugar can also be used.