Showing papers on "Thermal mass flow meter published in 1975"

Method and apparatus for mass flow rate measurement

Abstract: Apparatus and method for making fluid mass flow rate measurements using a Coriolis flow meter equipped with sensors which measure acceleration, velocity, or position of each side leg of an oscillating U-shaped conduit through which the fluid is passed. The sensors are so constructed and located as to produce analog signal outputs which accurately correspond to the motion of the respective side legs of the U-shaped conduit. When fluid is flowing through the conduit, a change from coincidence in the time relationship of the sensor signals caused by the divergent oscillations of each side leg of the U-shaped conduit is measured in both directions of oscillation. The fluid mass flow rate is then determined as a function of such time separation of the signals. The separation of the two signals with respect to time is measured without reference to static structures affixed to a platform.

Slurry Flow Velocity, Concentration and Particle Size Measurement Using Flow Noise and Correlation Techniques

Abstract: Three areas of slurry pipe flow measurement using flow noise and correlation techniques are described. Signals generated by the natural turbulence inherent in the flow of two-component fluids can be used to enable the total volume flow rate, concentration and particle size of the discontinuous component to be measured.Total volume flow is measured by a cross correlation method which involves obtaining the time of flight of a tagging signal due to the turbulence between two transducers spaced axially along the direction of flow. Both ultrasonic and conductivity transducers are used to detect the flow turbulence. Results show that a measurement accuracy within ±2% can be achieved in all systems tested. The intensity of the flow noise detected by a simple transducer is related to the quantity of the discontinuous component present in the flow. This flow noise is measured by an AC method and gives direct indication of the concentration of the discontinuous component. Turbulent flow consists of eddies which ha...

Digital output, positive displacement flow meter

Abstract: A positive displacement, reciprocating fluid flow meter produces a digital electrical output signal. The meter includes a piston which reciprocates within a cylinder for accurately measuring fuel flow rates over a wide range of rates. The device is particularly useful in measuring the rate of flow of fuel to an engine, and incorporates a valve for bypassing the piston to permit resetting of the meter at the end of each piston stroke.

Methods and apparatus for proof testing gas meters

Abstract: There is disclosed herein methods and apparatus for proof testing fluid meters, particularly gas meters of the positive displacement, diaphragm-operated type in which the number of cycles of operations of the valve mechanism of the meter is used as a factor in proving the accuracy of the meter, the number of said cycles being determined by sensing a series of pressure waveforms in the test gas entering and leaving the diaphragm chambers of the meter, which waveforms are characteristic of the particular meter being tested and occur in each cycle and reoccurring cycle of operation of the meter when operating, detecting a characteristic waveform in each series of waveforms amplifying and shaping the characteristic waveform and counting a predetermined number of cycles of said waveforms and comparing the volume of test gas which has passed through the meter as measured by a meter prover with the amount that should have passed during that predetermined number of cycles of operations of the meter. In the embodiment herein disclosed, the proving of the meter is carried out by maintaining a predetermined constant rate of flow of the test gas through the meter as by placing a sonic nozzle, a critical flow orifice or the like in the path of the test gas, such as air, which passes through the meter being tested for a measured length of time whereby the volume of the test air which actually passed through the meter may be determined to establish the proof of the meter.

Device for measuring the mass flow or flow rate of a gas

Abstract: A device for measuring the mass flow or flow rate of a gas which entrains ions produced by an electrode positioned in the path of the gas flow, this electrode being brought to a certain potential with respect to at least one other electrode also arranged in the flow path.

Apparatus for balancing the flow of two agents, capable of reacting together to provide energy, to an energy generator

Abstract: A device for metering the flow of two fluids, such as the flow of liquid fluid and air to an internal combustion engine, includes a respective duct for each of the two fluids, an ionic flow meter in each of the two ducts, a valve controlling the flow of one of the fluids through its duct and circuitry comparing the flow rates measured by the ionic flow meters and controlling the valve accordingly so as to maintain a desired ratio between the two flow rates

Mass flow meter for cryogenic fluid

Abstract: A mass flow meter including a fluid volume indicating means for measuring the volume of a fluid, a temperature sensor for indicating the temperature of the fluid being measured by the fluid volume indicating means, a density compensator connected to the volume indicating means and the temperature means to provide an indication of mass flow rate of the fluid material, and counting means to accurately accumulate the indication of mass units to provide the total mass of the fluid being measured. The signal output of the volume indicating means and the temperature sensor from the temperature sensor provide input pulses to the variable pulse width means in the density compensator to initiate an output measuring envelope pulse and to cut off the output measuring envelope pulse. The envelope pulse is an input density compensated envelope pulse to the counting means. The density compensator includes an oscillator producing a high frequency output to the counter means. The counter accumulates through the output of the density compensator the mass flow data to provide an indication of total mass of the fluid measured.

Flow control valve with internal rate of flow feedback

Abstract: A two-stage fluid flow control valve system employing feedback such that the rate of flow of fluid through the load connections follows an input signal very closely over a wide dynamic range. The system employs poppet valves as flow sensors in the return line. The rate of flow of fluid through these sensors is a non-linear function of the pressure thereacross such that the change in pressure drop resulting from a given displacement from a set flow rate is greater at low ranges of flow than at high ranges. The result is closer control at low rates of flow where such control is normally more difficult to achieve.

Meter for Sewer Flow Measurement

Abstract: An experimental and analytical study was performed to develop the geometry for a Venturi type flow meter for use in sewer flow measurement The meter consists of a constriction in the pipe which produces critical flow under open channel flow conditions and acts as a conventional Venturi meter under full flow conditions The constriction is constructed using cylindrical segments the diameter of which are larger than that of the pipe, leaving the invert and crown clear Head loss characteristics and experimental rating curves for both open channel and full flow conditions are described Information is also presented to permit the selection of geometrical parameters for optimum performance for a specific installation

The use of electronic prediction to achieve fast response from a simple thermal mass flow meter

Abstract: An electronic prediction network has been applied to the output of an inexpensive thermal mass flowmeter with a range of 0-100 cm3 min-1 at NTP. By this technique the time constant of the metering system was reduced from 15 s to less than 1 s.

Low pressure loss fluid flow meter

Abstract: A fluid flow meter comprising a flow tube of generally circular cross section in which is mounted a pair of generally semicircular vanes arranged for pivotal movement about a common diametral axis, said vanes being biased by resilient means into positions so as to close the tube and fluid flow indicating means for measuring gas flow rates in the range including flare gas flows and furnace combustion air flows.