Abstract: A method of determining volumetric flow rates of gas and liquid in a highly inclined conduit. The method includes measuring the velocity the gas, measuring the velocity of the liquid, calculating a fractional amount of the cross-sectional area of the conduit occupied by the gas and occupied by the liquid, and calculating the volumetric flow rates from the measurements of velocity and from the calculated fractional amounts of the cross-sectional area of the conduit occupied by the gas and by the liquid. In a preferred embodiment, the gas velocity is measured by cross-correlating measurements of two spaced apart temperature sensors after momentarily heating the gas. In the preferred embodiment, the liquid velocity is measured by a spinner flowmeter.

Abstract: The invention is a method of determining the flow regime of fluid having more than one phase flowing in a conduit. The method includes the step of positioning a sensor in the conduit, the sensor generating measurements capable of discriminating more than one phase in the fluids, generating measurements from the sensor for a period of time, characterizing the measurements with respect to changes in magnitude of the measurements occurring during the period of time, and comparing the characterized measurements to similarly characterized measurements of a similar sensor positioned within flow streams having known flow regimes.In a preferred embodiment of the invention, the characterization of the measurements includes performing a variability analysis of the measurements.