Compensation Method Applied to Coriolis Mass Flow Metering
F. Koschmieder, H. Röck
Abstract:
Coriolis mass flow meters (CMFM) are characterized by high accuracy and the ability to measure density and mass flow simultaneously. The sensitivity and zero point of the CMFM may change due to temperature gradients along the measuring pipe or mounting conditions. These changes have to be detected and corrected in order to as- sure high accuracy. A model based approach to estimate the zero point during normal operation and one-phase flow is presented. The approach exploits two characteristics of the measuring device: firstly the impact of mass flow upon the oscillation in the 2nd mode when the 1st mode is stimulated i.e. the operation principle of nearly all Coriolis mass flow meters and secondly the impact of mass flow upon the oscillation in the 1st mode when the 2nd mode is stimulated. Both of these characteristics are realized by compensation of Coriolis forces using MIMO-Phasor-Control.
Keywords:
Coriolis, mass flow, sensitivity, zero point, phasor control
