| abstract |
A flow rate measuring method for a multiphase fluid mixture flowing into a line is provided. The method comprises the steps of passing the fluid mixture through a Venturi tube having a pressure drop, measuring a differential pressure across the Venturi tube and a line pressure of the fluid mixture, measuring by a second measuring device, measured parameter(s) of the fluid mixture correlated to first and second phase relative quantities, determining estimated parameter(s) of the fluid mixture correlated to the first and second phase relative quantities based on the measured parameter and an extrapolating scheme, determining phase flow rate(s) based on the differential pressure, the line pressure and the measured parameter(s) of the fluid mixture, and determining flow rate(s) based on the differential pressure, the line pressure of the fluid mixture and the estimated parameter(s) of the fluid mixture. |