Vibrating conduit parameter sensors, methods and computer program products for generating residual-flexibility-compensated mass flow estimates

In a parameter sensor including a conduit configured to contain a material, a method of estimating a process parameter comprising the steps of:

• receiving a first plurality of motion signals representing motion of the conduit under a substantially zero mass flow condition;
• processing the received first plurality of motion signals to resolve the motion of the conduit under the substantially zero mass flow condition into a plurality of real normal modal components;
• estimating a real normal modal residual flexibility component from the resolved plurality of real normal modal components;
• receiving a second plurality of motion signals representing motion of the conduit;
• and
• generating a residual-flexibility-compensated estimate of mass flow from the received second plurality of motion signals and the estimated real normal modal residual flexibility component.

In a parameter sensor including a conduit configured to contain a material, a method of estimating a process parameter comprising the steps of:

• identifying a function operative to describe motion of the conduit in a real normal mode as function of frequency;
• determining a first value representing motion of the vibrating conduit at a selected frequency;
• estimating a real normal modal residual flexibility component associated with the real normal mode by fitting the first value to the identified function;
• receiving a plurality of motion signals representing motion of the conduit;
• and
• generating a residual-flexibility-compensated estimate of mass flow from the received second plurality of motion signals and the estimated real normal modal residual flexibility component.

An apparatus for estimating a process parameter from motion signals representing motion of a vibrating conduit containing a material, the apparatus comprising:

• a real normal modal residual flexibility component estimator including:
• means for identifying a function operative to describe motion of the conduit in a real normal mode as function of frequency;
• means, responsive to a plurality of motion signals representing motion of the conduit, for determining a first value representing motion of the vibrating conduit at a selected frequency;
• and
• means, responsive to said function identifying means and to said means for determining a first value, for estimating a real normal modal residual flexibility component associated with the real normal mode by fitting the first value to the identified function;
• and
• a residual-flexibility-compensated mass flow estimator, responsive to said real normal modal residual flexibility component estimator, for generating a residual-flexibility-compensated estimate of mass flow from the received second plurality of motion signals and the estimated real normal modal residual flexibility component.

A computer program product for estimating a process parameter associated with a material contained in a conduit, the computer program product comprising:

• a computer readable storage medium having computer readable program code means embodied in said medium, said computer readable program code means comprising:
• first computer-readable program code means for storing motion signals representing motion of the conduit;
• second computer-readable program code means, responsive to said first computer-readable program code means, for estimating a real normal modal residual flexibility component associated with a real normal mode of motion of the conduit;
• and
• third computer-readable program code means, response to said first computer-readable program code means and to said second computer-readable program code means, for generating a residual-flexibility-compensated estimate of mass flow from stored motion signals and the estimated real normal modal residual flexibility component.