Methodologies and apparatus for the recognition of production tests stability

Abstract

A method for analyzing flow of a fluid through a flowmeter is provided. In an embodiment, the method includes receiving multiphase flowmeter data representative of a characteristic of a multiphase fluid flowing through a multiphase flowmeter and segmenting the multiphase flowmeter data into time blocks. The data in the time blocks can be analyzed using time-domain analysis or frequency-domain analysis to determine flow stability. The time-domain analysis can include analyzing time blocks in a time domain to determine whether measurement distribution in the multiphase flowmeter data of the analyzed time blocks represents stable flow of the multiphase fluid. The frequency-domain analysis can include converting the multiphase flowmeter data of the time blocks from a time domain to a frequency domain and identifying time blocks in which contribution of low-frequency components in the frequency domain is below a contribution threshold. Additional systems, devices, and methods are also disclosed.

1 . An apparatus comprising:
 a fluid conduit;   a sensor coupled to the fluid conduit for measuring a characteristic of a multiphase fluid produced from a well and routed through the fluid conduit during a well production test; and   a computer operable to analyze the multiphase fluid characteristic measured by the sensor to determine a flow rate of the multiphase fluid through the fluid conduit, wherein the computer is also operable to determine flow stability of the well production test through analysis of the measured characteristic in both time and frequency domains.   
     
     
         2 . The apparatus of  claim 1 , wherein the computer is operable to: segment sensor data representative of the characteristic into time blocks, convert the time blocks from the time domain into the frequency domain with a Fourier transform, and check for the presence of long-term trends in the data by comparing an amplitude of the sensor data in the frequency domain to a pre-defined threshold. 
     
     
         3 . The apparatus of  claim 1 , wherein the sensor includes a differential pressure sensor for measuring the characteristic of the multiphase fluid. 
     
     
         4 . The apparatus of  claim 1 , wherein the sensor includes a radiation detector for measuring the characteristic of the multiphase fluid, the apparatus includes a radiation source, and the radiation source and the radiation detector are coupled to the fluid conduit such that the radiation detector can receive radiation transmitted from the radiation source into the fluid conduit. 
     
     
         5 . The apparatus of  claim 4 , wherein the radiation source and the radiation detector are coupled across a Venturi throat of the fluid conduit.