Other

Engineering Measurements Company

Dvco, Inc.

John F Waers

Charles E Miller

Randal L Custer

James A Magin

John T Lopez

Louis T Yoshida

Michael Steinbach

A vortex detector for low flow rates comprises a vane that is located downstream from a vortex generator and is connected at only one end in a canthever manner to a cylindrical housing, which defines a flow passage. The end of the vane connected to the housing includes an area of reduced thickness that acts as a resilient, plastic hinged joint to make it easier for weak vortices generated by the vortex generator to impart vibrations or deflections to of the vane. Strain gauge transducers in the area of reduced thickness detect deflections or vibrations of the vane and produce analog electric signals having amplitudes and frequencies that are related to the strengths, frequencies, and period of the vortices. The analog signals are converted to digital signals, which are indicative of strengths, frequencies, and periods of the vortices, but only such digital signals that result from corresponding analog signals with amplitudes above a threshold value are treated as originated from vortices action on the vane for purposes of determining vortex periods. Updated average vortex frequencies, calculated from vortex periods that are within an allowable deviation range, are used to determine instantaneous flow rates. The instantaneous flow rates are then processed through a smoothing function to stabilize flow rate outputs and displays.

Analog signal processing method for vortex detector

A vortex detector comprises a generally cylindrical housing or body that defines a flow passage extending from an upstream end to a downstream end. A vortex generator disposed diametrically across the cylindrical housing near the upstream end of the cylindrical housing and oriented substantially perpendicular to the longitudinal central axis of the flow passage generates a vortex street in a fluid flowing in the flow passage. The vortex street created by the vortex generator impacts a vane located downstream of the vortex generator and connected at one end to the cylindrical housing substantially spans the flow passage diametrically and substantially parallel to the vortex generator such that vibrations or motion are generated in the vane. The end of the vane connected to the housing includes an area of reduced thickness that acts as a resilient, elastic hinged joint for the motion of the vane. Strain gauge transducers in the area of reduced thickness detect deflections or vibrations of the vane caused by the vortices and produce electric signals having amplitudes and frequencies that are related to the strengths and frequencies of the passing vortices.

Vortex detector and flow meter

A supply plenum connected to a source of compressed natural gas (CNG) and a control valve assembly for selectively turning on the flow of CNG through a sonic nozzle and out through a dispensing hose assembly. Pressure and temperature transducers connected to the supply plenum measure the stagnation pressure and temperature of the CNG and the ambient temperature, and a pressure transducer fluidically connected to the vehicle tank via the dispensing hose assembly monitors the pressure of the CNG in the vehicle tank. An electronic control system connected to the pressure and temperature transducers and to the control valve assembly calculates a vehicle tank cut-off pressure based on the ambient temperature and on the pressure rating of the vehicle tank that has been pre-programmed into the electronic control system, calculates the volume of the vehicle tank and the additional mass of CNG required to increase the tank pressure to the cut-off pressure, and automatically turns off the CNG flow when the additional mass has been dispensed into the vehicle tank. The electronic control system also determines the amount of CNG dispensed through the sonic nozzle based on the upstream stagnation temperature and pressure of the CNG and the length of time the CNG was flowing through the sonic nozzle.

Method and apparatus for multiple-channel dispensing of natural gas

Method and apparatus for dispensing natural gas with pressure sensor

Method and apparatus for dispensing natural gas

A supply plenum connected to a source of compressed natural gas (CNG) and a control valve assembly for selectively turning on the flow of CNG through a sonic nozzle and out through a dispensing hose assembly. Pressure and temperature transducers connected to the supply plenum measure the stagnation pressure and temperature of the CNG and the ambient temperature, and a pressure transducer fluidically connected to the vehicle tank via the dispensing hose assembly monitors the discharge pressure of the CNG. An electronic control system connected to the pressure and temperature transducers and to the control valve assembly calculates a vehicle tank cut-off pressure based on the ambient temperature and on the pressure rating of the vehicle tank that has been pre-programmed into the electronic control system and automatically turns off the CNG flow when the discharge pressure reaches the cut-off pressure and determines the amount of CNG dispensed through the sonic nozzle based on the stagnation temperature and the stagnation pressure of the CNG and the length of time the CNG was flowing through the sonic nozzle.

Growing community of inventors

Longmont, CO, United States of America

John F Waers