Patent ID: 7484426
Filing Date: 2009-02-03
Classification: G01F

Abstract:
1. A method for providing a corrected flow parameter in a multiphasic process fluid flowmeter, the method comprising: obtaining a differential pressure value relative to differential pressure across a differential pressure producer disposed in piping conveying a multiphasic process fluid; obtaining a reference pressure value relative to the multiphasic process fluid; obtaining a temperature value relative to the multiphasic process fluid; obtaining a gas velocity of the multiphasic process fluid; calculating an overreading value based upon the differential pressure and the gas velocity; correcting the differential pressure based upon the overreading value; and determining if the differential pressure has converged by a selected amount and iterating if it has not converged; calculating a Lockhart-Martinelli parameter based upon known liquid density, a percentage of liquid in the fluid, the calculated gas velocity and a density of the gas; obtaining an overreading relationship based upon the reference pressure, the temperature, the gas velocity, and producer geometry information; and providing a multiphasic fluid flow value based upon the differential pressure once the differential pressure has converged by the selected amount, but feeding the Lockhart-Martinelli parameter and the overreading relationship back if the differential pressure has not converged by the selected amount, wherein at least one of the differential pressure value, the reference pressure value and the temperature value is communicated to the flowmeter through a process communication loop.