Abstract:
Methods, systems, devices, and products for evaluating a downhole fluid in a borehole intersecting an earth formation. Methods include using ultrasonic irradiation to produce sonoluminescence from cavitation in a volume of the fluid; obtaining spectral information from measurement of the sonoluminescence with a light-responsive device; and estimating a parameter of interest of the fluid from the spectral information. The parameter may be a composition of the fluid or concentration of: i) at least one chemical element in the volume; i) at least one molecular element in the volume. Methods include deconvolving a response spectrum by using one or more separately determined standard spectra, or estimating the parameter of interest using spectral lines represented by the spectral information. Methods may include using an optically transparent ultrasonic transducer to produce the cavitation at the interface of the transducer, with optically transparent ultrasonic transducer between the interface and the light-responsive device.
Abstract:
A method for determining the composition of fluids flowing through pipes from noninvasive measurements of acoustic properties of the fluid is described. The method includes exciting a first transducer located on the external surface of the pipe through which the fluid under investigation is flowing, to generate an ultrasound chirp signal, as opposed to conventional pulses. The chirp signal is received by a second transducer disposed on the external surface of the pipe opposing the location of the first transducer, from which the transit time through the fluid is determined and the sound speed of the ultrasound in the fluid is calculated. The composition of a fluid is calculated from the sound speed therein. The fluid density may also be derived from measurements of sound attenuation. Several signal processing approaches are described for extracting the transit time information from the data with the effects of the pipe wall having been subtracted.
Abstract:
A system and method for detecting and locating the interface emulsion or rag layer in a separator vessel makes use of an acoustic property approach or an imaging approach. Both approaches use ranging and longitudinal mode reflectance and are non-ionizing. The signals are sent through the fluid medium residing in different zones of the vessel, not through the vessel wall or a probe surrounded by the fluid medium. The acoustic property approach uses differences in acoustic impedance between the oil, rag, and water layers that create an echo detected by transit time measurement. Also, the velocity of sound, density, viscosity and attenuation can be calculated for each fluid in order to determine whether the medium is oil, rag, or water. The imaging approach uses differences in amplitude reflectance at these interfaces to create a brightness mode image of the different layers by each amplitude mode scan line being added spatially.
Abstract:
Methods are provided for characterizing the stability of a distillate fraction using a quartz crystal microbalance apparatus, such as a distillate fraction derived at least in part from a pre-refined crude oil. A sample can be aged for an aging period in a quartz crystal microbalance apparatus, and a frequency value for the sample in the quartz crystal microbalance apparatus can be determined before and after the aging period to determine a frequency difference. This frequency difference can be correlated directly with the ability of a jet fuel fraction to satisfy a stability test standard, such as a jet fuel breakpoint stability. The methods can also include using a temperature profile during characterization that can reduce or minimize operator error during the characterization.
Abstract:
Ultrasound tomography arrays and vortex shedding devices are provided which measure average flow velocity through Doppler shift of the fluid as well as cross sectional multiphase fluid composition in pipe or tubing conduits. Multiple tomographic arrays in conjunction with correlation of sensed flow patterns in time provided determination of flow velocity as well as cross sectional multiphase fluid composition. The tomographic arrays may be arranged in a skewed or slanted plane to measure velocity fluctuations downstream of a vortex shedding device where the period and amplitude of the fluctuations is correlated with the mass flow of the fluid. Additionally, the tomographic arrays provide the relative composition of the multiphase fluid. The multiple arrays together with correlation to determine velocity fluctuations downstream of a vortex shedding device where the period and amplitude of the fluctuations is correlated with the mass flow of the fluid. Additionally the tomographic arrays output the relative composition of the multiphase fluid.
Abstract:
A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.
Abstract:
Nonlinear sensors, which actively exploit dynamic transitions across sub-critical or saddlenode bifurcations in the device's frequency response, can exhibit improved performance metrics and operate effectively at smaller scales. This sensing approach directly exploits chemomechanically induced amplitude shifts for detection. Accordingly, it has the potential to eliminate the need for numerous power-consuming signal processing components in final sensor implementations. Various embodiments pertain to low-cost, linear and nonlinear bifurcation-based mass sensors founded upon selectively functionalized, piezoelectrically actuated microcantilevers. Yet other embodiments pertain to an amplitude-based sensing approach based upon dynamic transitions across saddle-node bifurcations that exist in a sensor's nonlinear frequency response.
Abstract:
A method for analysing a fluid containing one or more analytes of interest includes; measuring a plurality of properties of a sample fluid with unknown concentrations of the one or more analytes of interest; and using the measurements and a model of the relationship between the plurality of properties and concentrations of the one or more analytes to calculate the concentration of at least one of the analytes of interest. The model may be an artificial neural network. The method may be used to monitor the concentration of inhibitors of gas hydrate formation in a fluid. Apparatus for use in the method is also provided.
Abstract:
An apparatus and method to determine fractions of various phases in a multiphase fluid. The apparatus includes main body including an interior configured receive a multiphase fluid and an exterior. The apparatus senses fluid pressure of multiphase fluid received in the interior and senses a fluid temperature of the multiphase fluid. The apparatus transmits an ultrasonic wave into the fluid and detects the transmitted wave to determine its velocity and attenuation. The apparatus may adjust the determined velocity and attenuation based on the temperature and pressure of the fluid to compensate for a difference between the sensed temperature and pressure and a standard temperature and pressure. The apparatus determines a gas fraction, water fraction, and a non-water fluid fraction of the multiphase fluid based on the sensed fluid pressure, the sensed fluid temperature, and the velocity and attenuation of the ultrasonic wave in the multiphase fluid.
Abstract:
Disclosed is a method of realizing a dual mode acoustic wave sensor capable of being operated in both a gas environment and a liquid environment in a single chip by disposing a surface acoustic wave filter and a surface skimming bulk wave filter perpendicular to each other on the same wafer using the peculiar cut-orientation of an piezoelectric element, i.e. ST-cut quartz. An acoustic wave biosensor can realize optimum detection performance by detecting the characteristics of a detection environment and a detection target in real time during the operation of a dual mode sensor, and automatically switching between an SAW mode and an SSBW mode.