Vortex flowmeter with signal processing
AssigneeRosemount Inc.
InventorsLowell A. Kleven, Robert C. Hedtke, David E. Wiklund
Life of this patent
Estimating the term…
Abstract
A vortex sensor senses the vortices generated by a vortex generator. A temperature sensor, disposed at a streamlined body within a flow tube, measures a temperature of fluid carried by the flow tube. A circuit coupled to the vortex sensor and to the temperature sensor creates an output indicative of the flow.
Claims39
A vortex flowmeter, comprising:
- a flowtube having a vortex generator and a streamlined body disposed therein;
- a vortex sensor disposed relative to the vortex generator to detect vortices generated by the vortex generator;
- a temperature sensor disposed proximate the streamlined body to measure a temperature of fluid carried by the flowtube;
- and
- a circuit coupled to the vortex sensor and to the temperature sensor to provide an output indicative of fluid flow.
A vortex flowmeter providing an output value representative of a flow rate of a fluid, the vortex flowmeter comprising:
- a tube for fluid flow;
- a vortex sensor disposed relative to the tube to provide a vortex signal as a function of vortices generated in the tube;
- a filtering circuit operably coupled to the vortex sensor to receive the vortex signal and provide a filter output indicative of fluid flow;
- a temperature sensor disposed to sense a temperature of the fluid and provide a temperature value;
- and
- a processor operably coupled to the filtering circuit and the temperature sensor to receive the filter output and the temperature value, respectively, the processor calculating a calibration factor as a function of the filter output and the temperature value, and calculating the output value as a function of the calibration factor.
A vortex flowmeter providing an output value representative of a flow rate of a fluid, the vortex flowmeter comprising:
- a tube for fluid flow;
- a vortex sensor disposed to provide a vortex signal as a function of vortices generated in the tube;
- a filtering circuit operably coupled to the vortex sensor to receive the vortex signal and provide a filter output indicative of fluid flow;
- a temperature sensor disposed to sense a temperature of the fluid and provide a temperature value;
- a pressure sensor disposed to sense a pressure of the fluid and provide a pressure value;
- and
- a processor operably coupled to the filtering circuit, the temperature sensor and the pressure sensor to receive the filter output, the temperature value and the pressure value, respectively, the processor calculating a scaling constant as a function of the temperature value and the pressure value for applying to the filter output.
A flowmeter that measures a mass flow rate of fluid, comprising:
- a volumetric flow sensor disposed relative to the fluid to provide a volumetric output that varies as a function of a volumetric flow rate of the fluid;
- a streamlined body disposed in the fluid;
- a temperature sensor disposed proximate the streamlined body and having a temperature output;
- and
- a circuit receiving the volumetric output and the temperature output and providing a s a function thereof a flowmeter output representative of the mass flow rate of the fluid.
A method for calculating an output value representative of a mass flow rate of a flowing fluid, comprising the steps of:
- (a) providing a vortex generator that generates vortices in the fluid, a vortex sensor that measures at least one characteristic of the vortices, a temperature sensor that measures a temperature of the fluid, and a pressure sensor for measuring a pressure of the fluid;
- (b) calculating a first flow value from values obtained from the temperature sensor and the pressure sensor;
- (c) calculating a second flow value from values obtained from the vortex sensor;
- (d) calculating a calibration factor as a function of the first flow value and the second flow value;
- and
- (e) calculating an output mass flow rate as a function of the calibration factor and values obtained from the vortex sensor.
Dependencies are inferred from the claim text.