Topic
Thermal mass flow meter
About: Thermal mass flow meter is a research topic. Over the lifetime, 1759 publications have been published within this topic receiving 21878 citations.
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Patent•
28 Feb 2008
TL;DR: In this paper, a method and apparatus for measuring the temperature of a gas in a mass flow controller is described, which uses a thermal mass flow sensor to measure the gas temperature.
Abstract: A method and apparatus for measuring the temperature of a gas in a mass flow controller is described One embodiment denves gas-temperature information from a mass flow sensor of the mass flow controller without relying on a separate temperature sensor This embodiment supplies a substantially constant electrical current to a thermal mass flow sensor of the mass flow controller, the thermal mass flow sensor being designed to measure a mass flow rate of the gas, measures an input voltage of the thermal mass flow sensor to obtain a present input voltage, the input voltage varying with a temperature differential between a pair of sensing elements of the thermal mass flow sensor, calculates an adjusted input voltage by accounting for a component of the present input voltage that is dependent on the mass flow rate of the gas, and calculates the temperature of the gas based on adjusted input voltage.
25 citations
Patent•
27 Mar 2002
TL;DR: In this paper, the NH3 flow rate is measured using a hall effect sensor and a magnet mounted on a rotatable vane shaft 70 to overcome problems with prior flow meters.
Abstract: The present invention provides an apparatus and method for accurately controlling the amount of NH3 to be applied to a field by measuring the NH3 flow rate without condensing or cooling the NH3. The system includes a control station 12 on the vehicle with a tachometer 12A or a GPS system for providing a vehicle speed signal to a control panel 13. The control panel includes a toggle switch 17 for adjusting the opening or closing of a valve 52 in the flow line to regulate the flow through the system, although the control panel alternatively may automatically control the valve 52. The vehicle transports a tank 20 containing liquid NH3 and a tool bar 30 for distributing the NH3 to the soil. After flowing through the flow meter 40, 60, 130, the NH3 is conducted to the soil through a series of hoses, fittings, a distributor, and tubing. The flow meter transmits a signal to the control panel, which is converted to a corrected flow rate signal in response to a fixed value vaporization correction factor. The temperature of the NH3 is also measured to correct for density variations. An improved variable area meter 60, 130 uses a hall effect sensor 72 and a magnet 68 mounted on a rotatable vane shaft 70 to overcome problems with prior flow meters. The improved meter 60, 130 is ideally suited for measuring the fluid flow of a low temperature vaporization liquid, such as anhydrous ammonia, propane and butane.
25 citations
Patent•
[...]
TL;DR: In this article, phase fraction information with the total flow rate of the mixture is used to find individual flow rates for phases, such as oil, water, and gas or gas and liquid, which can represent a combination of oil and water phases.
Abstract: Methods and apparatus determine phase fractions for phases within a fluid mixture flow under a wide range of flow conditions including wet-gas flow. Appropriate flow algorithms can utilize this phase fraction information with a total flow rate of the mixture to find individual flow rates for phases, such as oil, water, and gas or gas and liquid, which can represent a combination of oil and water phases. For some embodiments, a multiphase flowmeter includes an array of spatially distributed pressure sensors configured to determine a velocity of the mixture flow and hence the total flow rate, which is applied with information from a differential pressure meter to calculate the bulk density of the fluid mixture. Further, additional speed of sound information or a water-in-liquid ratio as may be determined by spectral analysis can enable differentiation between the oil and water phases.
25 citations
Patent•
07 Apr 1993
TL;DR: In this paper, a hydrodynamic fluid divider is provided whereby by a shunt line directs a portion of the overall flow of a defined fluid stream through a flow measuring device, such as a Coriolis mass flow meter.
Abstract: A hydrodynamic fluid divider is provided whereby by a shunt line directs a portion of the overall flow of a defined fluid stream through a flow measuring device, such as a Coriolis mass flow meter. The proportion of the shunt line flow portion is determined by the relationship of various fluid restrictions within the shunt line and the main line of the divider. The measured flow value for the shunt line flow is utilized along with a scale-up factor to determine the overall flow through the divider. The proportional relationship of the shunt line to the overall flow permits a reduction in the size and operational requirements for the flow measuring device.
24 citations
Patent•
10 Nov 1983
TL;DR: In this paper, the disclosed thermal mass flow meter has a heat conductive case having a fine groove and a sensor pipe disposed in said fine groove so as to carry fluid flow to be measured.
Abstract: The disclosed thermal mass flow meter has a heat conductive case having a fine groove and a sensor pipe disposed in said fine groove so as to carry fluid flow to be measured.
24 citations