Correlation method for measurements of total and fractional immiscible media flow rates and a device for its embodiment

Abstract

The invention relates to measuring equipment and can be used in data-measuring systems in oil-producing and oil-processing industries for the determination of multiphase flow composition, in particular, for evaluation of the well production rate. The invention is based on obtaining maximum data on the structure of the multiphase flow by its scanning in each measuring section by rotating high-frequency electric and magnetic fields with one common carrier frequency of the scanning signal. The received scanning signals are independently processed with identification of the peakamplitude-frequency and gain-phase characterictics of the signals. The results of all measurements are used for calculating the correlation functions. The scanning signals generated by the rotating high-frequency electric field are scaled (signals are amplified by means of a normalizing scale factor). All four scanning signals are additionally processed by the microprocessor. Total and fractional flow rates are determined by comparing the measured characteristics with the reference characteristics in the database.

1 . A correlation method for measurements of total and fractional flow rates of multiphase immiscible media comprising: 
 two control sections on a pipeline that are located at a fixed distance from each other;    measurements of fluctuations of dielectric flow characteristics in each control section with scanning of the flow by the rotating high-frequency electric field and processing scanning signal to identify the area with a peak amplitude-frequency characteristic of the scanning signal;    recording the time of the flow transportation at the peak of the scanning signals' correlation function and determination of fractional volumes of multiphase immiscible media and total and fractional flow rates    distinguished in that the flow is additionally scanned in each control section by the rotating high-frequency magnetic field with the same carrier frequency of the signal; the scanning signals are processed by the rotating high-frequency magnetic field with identification of the area with a peak amplitude-frequency characterictic of the signals; the correlation function is calculated by using all four scanning signals; in the course of calculating the correlation function the amplitude of scanning signals generated by the rotating high-frequency electric field or the sum of the amplitudes of two said signals are scaled (normalized) and aligning their signal in relation to the scanning signal generated by the rotating magnetic field.    
   
   
       2 . A method as recited in  claim 1  distinguished in that high-frequency electric and magnetic signals with an adjustable carrier frequency of the signals in the 1-100 MHz range are used for the flow scanning.  
   
   
       3 . A method as recited in  claim 2  distinguished in that when scanning the flow, the carrier frequency of the scanning signal is altered stepwise and on each frequency the scanning signal is recorded in the fixed mode.  
   
   
       4 . A method as recited in  claim 3  distinguished in that the carrier frequency of the scanning signal changes with a 50-150 Hz step when changing-over to the next scanning frequency.  
   
   
       5 . A method as recited in  claim 1  distinguished in that when scanning the flow by the high-frequency magnetic field, the scanning signal is delivered with a time shift which equals the transportation time of the medium between the control cross-sections scanned by the electric and magnetic fields.  
   
   
       6 . A method as recited in  claim 1  distinguished in that the transportation time of the medium between two control sections is recorded and when further flow scanning is effected the scanning signals in the second control section are fed with a time delay which takes into account the transportation time of the medium.  
   
   
       7 . A method as recited in  claim 1  distinguished in that for determination of fractional composition of a multiphase medium the scaled amplitude-frequency characteristics of scanning by the electric and magnetic field are summed up; the composite characteristic is compared with the reference characteristics in the database which identifies most similar characteristics and fractional volumes of separate multiphase medium components are calculated by means of interpolation.  
   
   
       8 . A method as recited in  claim 1  distinguished in that resonance frequencies, phase shifts, actual and imaginary parts of the complex dielectric constant, actual and imaginary parts of magnetic losses are calculated by using recorded amplitude-frequency characteristics. The obtained values are compared with the reference characteristics in the database. The database identifies most similar combinations of specified characteristics and fractional composition of separate components of the multiphase medium is calculated by using interpolation.  
   
   
       9 . A method as recited in any claim  1 - 8  distinguished in that the temperature and pressure of the multiphase medium are additionally measured at least in one control section.  
   
   
       10 . A device for measurements of total and fractional flow rates of multiphase immiscible media comprising: 
 two measuring sections that are set apart from each other on a pipeline, each of these measuring sections being equipped with a unit for measurements of fluctuations of dielectric flow characteristics;    a high-frequency scanning signals generator coupled to said measuring units;    the first and the second units for measurements of amplitude-frequency characteristics;    a unit for calculating the correlation function and a control microprocessor.    Each unit for measurements of fluctuations of dielectric field characteristics is coupled to the unit for calculating the correlation function via its own first or second unit for measurements of amplitude-frequency characteristics. The device is distinguished in that each measuring section is additionally equipped with a unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow; each measuring section comprises the third and the fourth units for measurements of amplitude-frequency characteristics, the second unit for calculating the correlation function, a unit for scaling the amplitude-frequency characteristic of dielectric field fluctuations, a unit for the storage of reference amplitude-frequency characteristics of the multiphase flow and an external PC. At that all four units for measurements of fluctuations of electric and magnetic fields in the multiphase flow are coupled to the common high-frequency scanning signals generator. Each unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow via its own third or fourth unit for measurements of amplitude-frequency characteristics is coupled to the second unit for calculating the correlation function. The microprocessor's first input is coupled to the first unit for calculating the correlation function via the scaling unit; the microprocessor's second input is directly coupled to the second unit for calculating the correlation function, the microprocessor's third input is coupled to the unit for the storage of reference amplitude-frequency characteristics of the multiphase flow. The microprocessor's output is coupled to the external computer.    
   
   
       11 . A device as recited in  claim 10  distinguished in that it is equipped with a scanning signal tine delay unit which is set in the power supply line connecting the high-frequency scanning signals generator with the units for measurements of fluctuations of electric and magnetic fields in the multiphase flow of the second control section.  
   
   
       12 . A device as recited in  claim 10  distinguished in that there is a scanning signal time shift unit in the power supply line of each unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow.  
   
   
       13 . A device as recited in  claim 10  distinguished in that it is additionally equipped with temperature and pressure sensors set in a measuring section with their outputs coupled to the microprocessor.  
   
   
       14 . A device for measurements of total and fractional flow rates of multiphase immiscible media comprising: 
 two measuring sections that are set apart from each other on a pipeline, each of these measuring sections being equipped with a unit for measurements of fluctuations of dielectric flow characteristics;    a high-frequency scanning signals generator coupled to said measuring units;    the first and the second units for measurements of gain-phase frequency characteristics;    a unit for calculating the correlation function and a control microprocessor.    Each unit for measurements of fluctuations of dielectric field characteristics is coupled to the unit for calculating the correlation function via its own first or second unit for measurements of gain-phase frequency characteristics. The device is distinguished in that each measuring section is additionally equipped with a unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow; each measuring section comprises the third and the fourth units for measurements of gain-phase frequency characteristics, the second unit for calculating the correlation function, a unit for scaling the characteristics of dielectric field fluctuations, a unit for the storage of reference characteristics of the multiphase flow and an external PC. At that all four units for measurements of fluctuations of the electric and magnetic fields in the multiphase flow are coupled to the common high-frequency scanning signals generator. Each unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow via its own third or fourth unit for measurements of gain-phase frequency characteristics is coupled to the second unit for calculating the correlation function. The microprocessor's first input is coupled to the first unit for calculating the correlation function via the scaling unit, being directly coupled to the second unit for calculating the correlation function; the microprocessor's second input is coupled to the outputs of all four units for measurements of gain-phase frequency characteristics; the microprocessor's third input is coupled to the unit for the storage of reference characteristics of the multiphase flow. The microprocessor's output is coupled to the external computer.    
   
   
       15 . A device as recited in  claim 14  distinguished in that it is equipped with two time delay units for recorded signals that come from the first measuring section, the first unit being set in the channel for measurements of fluctuations of the scanning magnetic field at the output of the corresponding unit for measurements of gain-phase frequency characteristics and the second one being set in the channel for measurements of dielectric field fluctuations at the output of the corresponding unit for measurements of gain-phase frequency characteristics.  
   
   
       16 . A device as recited in  claim 14  distinguished in that it is equipped with a scanning signal time shift unit in the power supply line of each unit for measurements of fluctuations of the scanning magnetic field in the multiphase flow.  
   
   
       17 . A device as recited in  claim 14  distinguished in that it is equipped with a scanning signal time shift unit for recorded signals of magnetic field fluctuations which is set in the output of the first unit for calculating the correlation function.  
   
   
       18 . A device as recited in  claim 14  distinguished in that it is additionally equipped with temperature and pressure sensors incorporated in one of two measuring sections with their outputs coupled to the microprocessor's fourth input.