Abstract: An apparatus for measuring a parameter of a fluid passing through a pipe includes a spatial array of at least two sensors disposed at different axial locations along the pipe. Each of the sensors provides a signal indicative of unsteady pressure within the pipe at a corresponding axial location of the pipe. A signal processor constructs at least a portion of a k-? plot using the signals and detects at least one ridge in the k-? plot. A slope of the at least one ridge is indicative of the parameter of the fluid. The signal processor determines a quality metric by comparing an accumulated energy (power) of k-? pairs along the at least one ridge with an accumulated energy (power) of k-? pairs along at least one ray extending in the k-? plot. The quality metric is indicative of a quality of the at least one ridge.

Abstract: A method and apparatus are provided for calibrating a flow meter having an array of sensors arranged in relation to a pipe that measures a flow rate of a fluid flowing in the pipe. The method features the step of calibrating the flow rate using a calibration correction function based on one or more parameters that characterize either the array of sensors, the pipe, the fluid flowing in the pipe, or some combination thereof. The calibration correction function depends on either a ratio t/D of the pipe wall thickness (t) and the pipe inner diameter (D); a ratio t/? of the pipe wall thickness (t) and the eddie wavelength (?) of the fluid; a Reynolds number (?UD/?) that characterizes the fluid flow in the pipe; a ratio ?x/D of the sensor spacing (?x) and the pipe inner diameter (D); a ratio f?x/Umeas of usable frequencies in relation to the sensor spacing (?x) and the raw flow rate (Umeas); or some combination thereof.

Abstract: A flow measuring system combines a density measuring device and a device for measuring the speed of sound (SOS) propagating through the fluid flow and/or for determining the gas volume fraction (GVF) of the flow. The GVF meter measures acoustic pressures propagating through the fluids to measure the speed of sound ?mix propagating through the fluid to calculate at least gas volume fraction of the fluid and/or SOS. In response to the measured density and gas volume fraction, a processing unit determines the density of non-gaseous component of an aerated fluid flow. For three phase fluid flows, the processing unit can determine the phase fraction of the non-gaseous components of the fluid flow. The gas volume fraction (GVF) meter may include a sensing device having a plurality of strain-based or pressure sensors spaced axially along the pipe for measuring the acoustic pressures propagating through the flow.

Abstract: Various methods are described which increase the efficiency and accuracy of a signal processor in determining parameters of a fluid using signals output by a spatial array of sensors disposed along a pipe. In one aspect, parameters used for calculating the temporal Fourier transform of the pressure signals, specifically the amount or duration of the data that the windowing function is applied to and the temporal frequency range, are adjusted in response to the determined parameter. In another aspect, an initialization routine estimates flow velocity so the window length and temporal frequency range can be initially set prior to the full array processing. In another aspect, the quality of one or more of the parameters is determined and used to gate the output of the apparatus in the event of low confidence in the measurement and/or no flow conditions. In another aspect, a method for determining a convective ridge of the pressure signals in the k-? plane is provided.

Abstract: A device for measurement of entrained and dissolved gas has a first module arranged in relation to a process line for providing a first signal containing information about a sensed entrained air/gas in a fluid or process mixture flowing in the process line at a process line pressure. The device features a combination of a bleed line, a second module and a third module. The bleed line is coupled to the process line for bleeding a portion of the fluid or process mixture from the process line at a bleed line pressure that is lower than the process pressure. The second module is arranged in relation to the bleed line, for providing a second signal containing information about a sensed bleed line entrained air/gas in the fluid or process mixture flowing in the bleed line.

Abstract: An apparatus 10,110 is provided that measures the speed of sound or acoustic disturbances propagating in a fluid or mixture having entrained gas/air to determine the gas volume fraction of the flow 12 propagating through a pipe 14. The apparatus includes an array of pressure sensors disposed axially along the length of the pipe. The apparatus measures the speed of sound propagating through the fluid to determine the gas volume fraction of the mixture using adaptive array processing techniques to define an acoustic ridge in the k-? plane. The slope of the acoustic ridge 61 defines the speed of sound propagating through the fluid in the pipe.

Abstract: An apparatus 10 is provided that includes a spatial array of at least two unsteady pressure sensors 18–21 placed at predetermined axial locations x1–xN disposed axially along a pipe 14 for measuring at least one parameter of a fluid 12 flowing in the pipe 14. The pressure sensors 18–21 comprise a plurality of pressure sensing elements such as piezoelectric film sensors 23 for measuring unsteady pressures associated with acoustical pressures and/or vortical disturbances. The sensing elements are disposed circumferentially around the pipe and spaced a predetermined distance. The pressure signals P1(t)–PN(t) provided by the pressure sensors 18–21 are processed by a processing unit to provide an output signal indicative of a parameter of the fluid.

Abstract: An apparatus 10,70 and method is provided that includes a spatial array of unsteady pressure sensors 15–18 placed at predetermined axial locations x1–xN disposed axially along a pipe 14 for measuring at least one parameter of a saturated vapor/liquid mixture 12, such as steam, flowing in the pipe 14. The pressure sensors 15–18 provide acoustic pressure signals P1(t)–PN(t) to a signal processing unit 30 which determines the speed of sound amix propagating through of the saturated vapor/liquid mixture 12 in the pipe 14 using acoustic spatial array signal processing techniques. The primary parameters to be measured include vapor/liquid concentration (i.e., steam wetness or steam quality), vapor/liquid mixture volumetric flow, mass flow, enthalpy, density and liquid droplet size. Frequency based sound speed is determined utilizing a dispersion model to determine the parameters of interest.

Abstract: A method for detecting the presence of particles, such as sand, flowing within a fluid in a conduit is disclosed. At least two optical sensors measure pressure variations propagating through the fluid. These pressure variations are caused by acoustic noise generated by typical background noises of the well production environment and from sand particles flowing within the fluid. If the acoustics are sufficiently energetic with respect to other disturbances, the signals provided by the sensors will form an acoustic ridge on a k? plot, where each data point represents the power of the acoustic wave corresponding to that particular wave number and temporal frequency. A sand metric then compares the average power of the data points forming the acoustic ridge to the average power of the data points falling outside of the acoustic ridge. The result of this comparison allows one to determine whether particles are present within the fluid.

Abstract: A method for detecting the presence of particles, such as sand, flowing within a fluid in a conduit is disclosed. At least two optical sensors measure pressure variations propagating through the fluid. These pressure variations are caused by acoustic noise generated by typical background noises of the well production environment and from sand particles flowing within the fluid. If the acoustics are sufficiently energetic with respect to other disturbances, the signals provided by the sensors will form an acoustic ridge on a k? plot, where each data point represents the power of the acoustic wave corresponding to that particular wave number and temporal frequency. A sand metric then compares the average power of the data points forming the acoustic ridge to the average power of the data points falling outside of the acoustic ridge. The result of this comparison allows one to determine whether particles are present within the fluid.

Abstract: A apparatus 10,110 is provided that measures the speed of sound and/or vortical disturbances propagating in a fluid or mixture having entrained gas/air to determine the gas volume fraction of the flow 12 propagating through a pipes and compensating or correcting the volumetric flow measurement for entrained air. The GVF meter includes and array of sensor disposed axially along the length of the pipe. The GVF measures the speed of sound propagating through the pipe and fluid to determine the gas volume fraction of the mixture using array processing. The GVF meter can be used with an electromagnetic meter and a consistency meter to compensate for volumetric flow rate and consistency measurement respective, to correct for errors due to entrained gas/air.

Abstract: An apparatus 10 is provided that includes a spatial array of at least two unsteady pressure sensors 18-21 placed at predetermined axial locations x1-xN disposed axially along a pipe 14 for measuring at least one parameter of a fluid 12 flowing in the pipe 14. The pressure sensors 18-21 comprise a plurality of pressure sensing elements such as piezoelectric film sensors 23 for measuring unsteady pressures associated with acoustical pressures and/or vortical disturbances. The sensing elements are disposed circumferentially around the pipe and spaced a predetermined distance. The pressure signals P1(t)-PN(t) provided by the pressure sensors 18-21 are processed by a processing unit to provide an output signal indicative of a parameter of the fluid.

Abstract: An apparatus 10,110 is provided that measures the speed of sound or acoustic disturbances propagating in a fluid or mixture having entrained gas/air to determine the gas volume fraction of the flow 12 propagating through a pipe 14. The apparatus includes an array of pressure sensors disposed axially along the length of the pipe. The apparatus measures the speed of sound propagating through the fluid to determine the gas volume fraction of the mixture using adaptive array processing techniques to define an acoustic ridge in the k-&ohgr; plane. The slope of the acoustic ridge 61 defines the speed of sound propagating through the fluid in the pipe.

Abstract: A device for measurement of entrained and dissolved gas has a first module arranged in relation to a process line for providing a first signal containing information about a sensed entrained air/gas in a fluid or process mixture flowing in the process line at a process line pressure. The device features a combination of a bleed line, a second module and a third module. The bleed line is coupled to the process line for bleeding a portion of the fluid or process mixture from the process line at a bleed line pressure that is lower than the process pressure. The second module is arranged in relation to the bleed line, for providing a second signal containing information about a sensed bleed line entrained air/gas in the fluid or process mixture flowing in the bleed line.

Abstract: A method for detecting the presence of particles, such as sand, flowing within a fluid in a conduit is disclosed. At least two optical sensors measure pressure variations propagating through the fluid. These pressure variations are caused by acoustic noise generated by typical background noises of the well production environment and from sand particles flowing within the fluid. If the acoustics are sufficiently energetic with respect to other disturbances, the signals provided by the sensors will form an acoustic ridge on a k&ohgr; plot, where each data point represents the power of the acoustic wave corresponding to that particular wave number and temporal frequency. A sand metric then compares the average power of the data points forming the acoustic ridge to the average power of the data points falling outside of the acoustic ridge. The result of this comparison allows one to determine whether particles are present within the fluid.

Abstract: A method and apparatus are provided for calibrating a flow meter having an array of sensors arranged in relation to a pipe that measures a flow rate of a fluid flowing in the pipe. The method features the step of calibrating the flow rate using a calibration correction function based on one or more parameters that characterize either the array of sensors, the pipe, the fluid flowing in the pipe, or some combination thereof. The calibration correction function depends on either a ratio t/D of the pipe wall thickness (t) and the pipe inner diameter (D); a ratio t/&lgr; of the pipe wall thickness (t) and the eddie wavelength (X) of the fluid; a Reynolds number (&rgr;UD/&mgr;) that characterizes the fluid flow in the pipe; a ratio &Dgr;x/D of the sensor spacing (&Dgr;x) and the pipe inner diameter (D); a ratio f&Dgr;x/Umeas of usable frequencies in relation to the sensor spacing (&Dgr;x) and the raw flow rate (Umeas); or some combination thereof.

Abstract: A apparatus 10,110 is provided that measures the speed of sound and/or vortical disturbances propagating in a fluid or mixture having entrained gas/air to determine the gas volume fraction of the flow 12 propagating through a pipes and compensating or correcting the volumetric flow measurement for entrained air. The GVF meter includes and array of sensor disposed axially along the length of the pipe. The GVF measures the speed of sound propagating through the pipe and fluid to determine the gas volume fraction of the mixture using array processing. The GVF meter can be used with an electromagnetic meter and a consistency meter to compensate for volumetric flow rate and consistency measurement respective, to correct for errors due to entrained gas/air.

Abstract: A probe 10,170 is provided that measures the speed of sound and/or vortical disturbances propagating in a single phase fluid flow and/or multiphase mixture to determine parameters, such as mixture quality, particle size, vapor/mass ratio, liquid/vapor ratio, mass flow rate, enthalpy and volumetric flow rate of the flow in a pipe or unconfined space, for example, using acoustic and/or dynamic pressures. The probe includes a spatial array of unsteady pressure sensors 15-18 placed at predetermined axial locations x1-xN disposed axially along a tube 14.for measuring at least one parameter of a saturated vapor/liquid mixture 12, such as steam, flowing in the tube 14. The pressure sensors 15-18 provide acoustic pressure signals P1(t)-PN(t) to a signal processing unit 30 which determines the speed of sound amix propagating through of the saturated vapor/liquid mixture 12 in the tube 14 using acoustic spatial array signal processing techniques.

Abstract: An apparatus 10,70 and method is provided that includes a spatial array of unsteady pressure sensors 15-18 placed at predetermined axial locations xl-xN disposed axially along a pipe 14.for measuring at least one parameter of a saturated vapor/liquid mixture 12, such as steam, flowing in the pipe 14. The pressure sensors 15-18 provide acoustic pressure signals P1(t)-PN(t) to a signal processing unit 30 which determines the speed of sound amix propagating through of the saturated vapor/liquid mixture 12 in the pipe 14 using acoustic spatial array signal processing techniques. The primary parameters to be measured include vapor/liquid concentration (i.e., steam wetness or steam quality), vapor/liquid mixture volumetric flow, mass flow, enthalpy, density and liquid droplet size. Frequency based sound speed is determined utilizing a dispersion model to determine the parameters of interest.

Abstract: An apparatus 10,70 and method is provided that includes a spatial array of unsteady pressure sensors 15-18 placed at predetermined axial locations X1-XN disposed axially along a pipe 14. for measuring at least one parameter of a solid particle/fluid mixture 12 flowing in the pipe 14. The pressure sensors 15-18 provide acoustic pressure signals P1(t)-PN(t) to a signal processing unit 30 which determines the speed of sound amix of the particle/fluid mixture 12 in the pipe 14 using acoustic spatial array signal processing techniques. The primary parameters to be measured include fluid/particle concentration, fluid/particle mixture volumetric flow, and particle size. Frequency based sound speed is determined utilizing a dispersion model to determine the parameters of interest.