摘要:
A apparatus 10,110,170 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, by measuring acoustic and/or dynamic pressures. The apparatus includes a spatial array of unsteady pressure sensors 15-18 placed at predetermined axial locations x1-xN disposed axially along 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 process flow 12 flowing in the pipe 14. The pressure sensors are piezoelectric film sensors that are mounted or clamped onto the outer surface of the pipe at the respective axial location.
摘要:
A flow measuring system is provided that provides at least one of a compensated mass flow rate measurement and a compensated density measurement. The flow measuring system includes a gas volume fraction meter in combination with a coriolis meter. The GVF meter measures acoustic pressures propagating through the fluids to measure the speed of sound αmix propagating through the fluid to calculate at least gas volume fraction of the fluid and/or the reduced natural frequency. For determining an improved density for the coriolis meter, the calculated gas volume fraction and/or reduced frequency is provided to a processing unit. The improved density is determined using analytically derived or empirically derived density calibration models (or formulas derived therefore), which is a function of the measured natural frequency and at least one of the determined GVF, reduced frequency and speed of sound, or any combination thereof. 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.
摘要:
A parameter of a fluid passing through a pipe is measured using a spatial array of sensors disposed at different axial locations along the pipe. The spatial array includes at least two overlapping sub-arrays. Using the pressure signals, a signal processor determines a spatial correlation matrix for each of the sub arrays. The spatial correlation matrices from the sub-arrays are averaged, and the averaged spatial correlation matrix is used as input to an adaptive array processing algorithm. The pipe may be open ended such that it can be positioned within the fluid flow for forming a portion of a sensing device.
摘要:
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 αmix 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.
摘要:
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-ω plot using the signals and detects at least one ridge in the k-ω 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-ω pairs along the at least one ridge with an accumulated energy (power) of k-ω pairs along at least one ray extending in the k-ω plot. The quality metric is indicative of a quality of the at least one ridge.
摘要:
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/λ of the pipe wall thickness (t) and the eddie wavelength (λ) of the fluid; a Reynolds number (ρUD/μ) that characterizes the fluid flow in the pipe; a ratio Δx/D of the sensor spacing (Δx) and the pipe inner diameter (D); a ratio fΔx/Umeas of usable frequencies in relation to the sensor spacing (Δx) and the raw flow rate (Umeas); or some combination thereof. The apparatus takes the form of a flow meter having a calibration correction function module performing the aforementioned functionality.
摘要:
A clamp on 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 clamped onto the exterior of the pipe and 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-ω plane. The slope of the acoustic ridge 61 defines the speed of sound propagating through the fluid in the pipe.
摘要:
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.
摘要:
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 kω 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. Furthermore, the present invention can also determine whether the generated acoustic noise is occurring upstream or downstream of the sensors, thus giving an indication of the location of the particles in the fluid relative to the sensors.
摘要:
An apparatus is provided for measuring total gas content of a fluid flowing through a process line. The apparatus comprises a bleed line in fluid communication with the process line for bleeding a portion of the fluid from the process line at a bleed line pressure that is lower than the process line pressure. A speed of sound propagating through the fluid in the bleed line is determined and is, in turn, used to determine a gas volume fraction of the fluid in the bleed line. In one aspect, the total gas content of the fluid flowing through the process line is calculated as a function of the gas volume fraction of the fluid in the bleed line and a velocity of the fluid in the bleed line. In another aspect, the velocity of the fluid in the bleed line is adjusted to be approximately equal to a predetermined velocity. In yet another aspect, dissolved gas in the process fluid 13 is released before the gas content measurement point by applying a high intensity ultrasonic field to the fluid 13.