Entropy based multiphase flow detection

A multiphase fluid flow (MPF) characterization system to enhance measuring and monitoring of a flow regime in a segment of pipe for hydrocarbon-production operations, the system comprising:

• an acoustic receiver disposed proximate to the segment of pipe and operable to receive an acoustic signal transmitted through a MPF, the segment of pipe operable to support the MPF in hydrocarbon-production operations including at least two physical phases, and the acoustic receiver operable to convert the received acoustic signal to an electrical signal;
• an acoustic transmitter disposed proximate to the segment of pipe and operable to convey an acoustic signal through the MPF in hydrocarbon-production operations, further operable to convey the acoustic signal such that the acoustic signal is receivable by the acoustic receiver;
• a processing unit, including a processor, operable to receive the electrical signal and transform the electrical signal to characterize the MPF, the processing unit in communication with and comprising:
• non-transitory, tangible memory medium in communication with the processor having a set of stored instructions, the set of stored instructions being executable by the processor and including the steps of:
• segmenting the electrical signal into short term, medium term, and long term time series;
• assigning positive real numbers to the time series, the positive real numbers including larger values and smaller values, the larger values corresponding to process randomness, and the smaller values corresponding to instances of recognizable patterns in the electrical signal;
• categorizing certain positive real numbers as outlier values;
• calculating short term, medium term, and long term approximate entropy values for the MPF based upon the short term, medium term, and long term time series from the electrical signal by performing the following steps:
• assigning each of the short term, medium term, and long term time series of data to variables each representing raw data values measured at equally spaced time intervals,
• forming a sequence of vectors using the variables each representing raw data values,
• using the sequence of vectors to construct scalar components representing the distance between each respective vector sequence given by the maximum difference in their respective scalar components,
• calculating each of the short term, medium term, and long term time series approximate entropy values using the scalar components,
• comparing the short term, medium term, and long term approximate entropy values for the MPF to pre-determined short term, medium term, and long term approximate entropy values;
• and
• determining characteristics of the MPF responsive to similarities between the short term, medium term, and long term approximate entropy values for the MPF and the pre-determined short term, medium term, and long term approximate entropy values;
• and
• a user interface coupled to the processing unit, the user interface operable to accept user inputs to control the processing unit, and operable to display the characteristics of the MPF to a user.