Patent ID: 7571633

Claim:
An apparatus for determining a total gas content of a fluid flow passing through a pipe; said apparatus comprising: a bleed line coupled to the pipe for bleeding a portion of the fluid flow from the pipe at a bleed line pressure that is lower than the pressure of the fluid flow within the pipe, wherein the bleed line is sized to maintain flow rate sufficient to minimize slip between the gas and liquid phases of the fluid flow within a bleed test section such that a measured gas phase fraction of the fluid flow within the bleed test section is representative of the gas phase fraction of total gas content in the fluid flow in the pipe; and a meter that determines the gas phase fraction of the fluid flow passing through the bleed test section of the bleed line, the meter having an array of sensors with at least two sensors configured for measuring the speed of sound propagating through the fluid flow in the bleed line to determine the gas phase fraction of the fluid flow in the bleed line, the meter being configured to determine the speed of sound passing through the fluid flow by determining the slope of an acoustic ridge in a k-ω plane.