A multiphase fluid flow characterization system (100, 200) adapted to enhance measuring and monitoring of a flow regime in a segment of pipe for hydrocarbon-production operations, the system comprising: an acoustic emission sensor disposed proximate to the segment of pipe and operable to receive an acoustic emission from a MPF, the segment of pipe operable to support the MPF in hydrocarbon-production operations including at least two physical phases, and the acoustic emission sensor operable to convert the received acoustic emission to an electrical signal; a processing unit, including a processor operable to receive the electrical signal and transform the electrical signal to characterize the MPF, the processing unit comprising: non-transitory, tangible memory medium in communication with the processor, the non-transitory, tangible memory medium 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 responsive to the short term, medium term, and long term time series from the electrical signal; 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. an acoustic emission sensor disposed proximate to the segment of pipe and operable to receive an acoustic emission from a MPF, the segment of pipe operable to support the MPF in hydrocarbon-production operations including at least two physical phases, and the acoustic emission sensor operable to convert the received acoustic emission to an electrical signal; a processing unit, including a processor operable to receive the electrical signal and transform the electrical signal to characterize the MPF, the processing unit comprising: non-transitory, tangible memory medium in communication with the processor, the non-transitory, tangible memory medium 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 responsive to the short term, medium term, and long term time series from the electrical signal; 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 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 responsive to the short term, medium term, and long term time series from the electrical signal; 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.