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Showing papers on "Thermal mass flow meter published in 2005"


Patent
09 Nov 2005
TL;DR: In this article, a thermal anemometer or mass flow meter having temperature and flow velocity sensor elements is provided in which a thin-film temperature sensor is captured at least partially within a spacer or interface member, the spacer being received within a housing.
Abstract: A thermal anemometer or mass flow meter having temperature and flow velocity sensor elements is provided in which a thin film temperature sensor is provided in the heated sensor of the fluid velocity sensor element of the system. The thin-film sensor is captured at least partially within a spacer or interface member, the spacer being received within a housing. The thermal anemometer is constructed to offer sufficient precision and accuracy in its design to be suitable for sensitive scientific and industrial applications. This goal is achieved while using cost effective parts—as in the thin film temperature sensor(s)—in connection with a construction approach minimizing or eliminating gaps or other system configuration variability.

172 citations


Journal ArticleDOI
TL;DR: In this paper, the authors present a theoretical analysis of the spatial sensitivity of the electrostatic meter with ring-shaped electrodes in the time and frequency domains, and the experimental data presented in this paper support the overall mathematic modeling, based on electrostatic field theory.

56 citations


BookDOI
01 Jan 2005
TL;DR: Fully developed Turbulent Pipe Flow. as mentioned in this paper describes the effect of area changes in Swirling Flow and how to correct the error shift of an Ultrasonic Flow Meter Downstream of installation.
Abstract: Fully Developed Turbulent Pipe Flow. - Decay of Disturbances in Turbulent Pipe Flow. - Optimal Characteristic Parameters for the Disturbances in Turbulent Pipe Flow. - Measurement of Velocity and Turbulence Downstream of Flow Conditioners. - Signal processing of Complex Modulated Ultrasonic Signals. - Vortex-Shedding Flow Metering Using Ultrasound. - Ultrasonic Gas-Flow Measurement Using Correlation Methods. - Ultrasound Cross-Correlation Flow Meter: Analysis by System Theory and Influence of Turbulence. - Effect of Area Changes in Swirling Flow. - Errors of Turbine Meters due to Swirl. - Investigation of Unsteady Three-Dimensional Flow Fields in a Turbine Flow Meter. - How to Design a New Flow Meter from Scratch. - Effects of Disturbed Inflow on Vortex Shedding from a Bluff Body. - Correction of the Reading of a Flow Meter in Pipe Flow Disturbed by Installation Effects. - How to Correct the Error Shift of an Ultrasonic Flow Meter Downstream of Installations.

30 citations


Patent
31 Jan 2005
TL;DR: A flow switch used in conjunction with a fuel meter in a fuel dispenser to determine when fuel is flowing is discussed in this article, where it is shown that if the meter pulser is registering fuel flow, but the flow switch is not registering fuel flows, then an error exists with the switch.
Abstract: A flow switch used in conjunction with a fuel meter in a fuel dispenser to determine when fuel is flowing. A flow switch can only be activated if fuel is flowing through the flow path of the flow switch. If fuel is flowing as indicated by the fuel flow switch, but the meter is not registering fuel flow, there is a meter error, which may be an error internally with components of the meter and/or a pulser that generates pulse signals indicative of fuel flow. If the meter pulser is registering fuel flow, but the flow switch is not registering fuel flow, then an error exists with the flow switch. If fuel is flowing and there are no errors, both the meter and the flow switch should indicate fuel flow.

28 citations


Patent
James L. Sprague1
22 Jul 2005
TL;DR: In this paper, a program product to measure fluid flow characteristics in a pipeline is provided, which includes instructions for a fluid characteristic determiner to perform the operations of processing measured and sensed signals to produce an output of a volumetric flow rate, a flowing fluid density, and a mass flow rate.
Abstract: Program product to measure fluid flow characteristics in a pipeline is provided. A vortex-shedding body is positioned within the pipeline to form vortices. A vortex meter can include a vortex frequency sensor to measure the frequency of the vortices to determine the volumetric flow rate. A differential pressure meter positioned adjacent the vortex-shedding body can produce a differential pressure meter flow rate signal indicative of the density of fluid when flowing through the pipeline. A thermal flow meter positioned adjacent the vortex-shedding body can produce a mass flow rate signal indicative of the mass flow rate of fluid when flowing through the pipeline. The program product can include instructions for a fluid characteristic determiner to perform the operations of processing measured and sensed signals to produce an output of a volumetric flow rate, a flowing fluid density, and a mass flow rate to be displayed on a fluid characteristic display.

23 citations


Patent
Wayne M. Parent1
15 Feb 2005
TL;DR: In this paper, a flow measurement device is used to determine a flow condition in a high pressure processing system, which can be defined as a volume flow rate or a mixing time to achieve mixing of a process chemistry within high pressure fluid used to treat the substrate.
Abstract: In a high pressure processing system configured to treat a substrate, a flow measurement device is utilized to determine a flow condition in the high pressure processing system. The flow measurement device can, for example, comprise a turbidity meter. The flow parameter can, for example, include a volume flow rate or a time to achieve mixing of a process chemistry within a high pressure fluid used to treat the substrate.

22 citations


Patent
14 Dec 2005
TL;DR: In this article, an ultrasonic flow meter for measuring a flow rate of a fluid flowing in a primary flow direction is described, where a velocity component is transferred to at least one part of the flowing fluid perpendicular to the primary flow.
Abstract: The measurement of volume flows or mass flows in the intake system of motor vehicle internal combustion engines plays a significant role in reducing pollutant emissions. Therefore, an ultrasonic flow meter for measuring a flow rate of a fluid flowing in a primary flow direction is described. The ultrasonic flow meter has at least two ultrasonic transducers, the ultrasonic transducers being capable of emitting and/or receiving ultrasonic waves at an angle α to the primary flow direction which is different from 90°. Furthermore, the ultrasonic flow meter has at least one guide element which is entirely or partially situated in the fluid. This guide element diverts at least one part of the flowing fluid in such a way that in the diversion, a velocity component is transferred to at least one part of the flowing fluid perpendicular to the primary flow direction. Guide vanes or displacers in particular are described as guide elements. In addition, turbulators may be provided on the guide elements, the turbulators generating a longitudinal fluid bed along the guide elements and thus causing the flow of the fluid to have a better contact with the guide elements when flowing around them. This reduces turbulences within the ultrasonic flow meter. Compared to the devices known from the related art, the ultrasonic flow meters described are distinguished by an improved signal-to-noise ratio and accordingly by a higher measuring precision.

22 citations


Journal ArticleDOI
TL;DR: In this paper, an experimental study on Pb-Bi water direct contact boiling two-phase flow has been performed using PbBi-water direct contact boil water small fast reactor (PBWFR), where a stable single-phase natural circulation was realized in the range of flow rate from 1.5 l/min to 4.8 l /min by heating Pb Bi in the heaterpin bundle with a power up to 7.7 kW.

20 citations


Journal ArticleDOI
TL;DR: In this paper, a simple numerical model for transient heat transfer phenomena involving the sensor tube of a thermal mass flow meter (TMFM) is presented, and a correlation for predicting the response time of the tube is presented.

18 citations


Patent
Hans Hecht1, Roland Mueller1, Uwe Konzelmann1, Tobias Lang1, Sami Radwan1 
26 Aug 2005
TL;DR: In this article, an ultrasonic flow rate meter and a method for measuring the flow rate with the aid of ultrasound are described, having at least two ultrasonic transducers situated offset in a flow channel in the flow direction for transmitting and receiving ultrasound wave packets, so that ultrasound propagation times from one of the transducers to the other, and vice-versa, can be determined in an electronic part.
Abstract: An ultrasonic flow rate meter and a method for measuring the flow rate with the aid of ultrasound are described, having at least two ultrasonic transducers situated offset in a flow channel in the flow direction for transmitting and receiving ultrasound wave packets, so that ultrasound propagation times from one of the ultrasonic transducers to the other, and vice-versa, can be determined in an electronic part, and having a pressure sensor associated with the flow channel for determining the pressure in the flow channel. Measured values for an engine control that is as accurate as possible are determinable by accurately detecting the incoming air in the intake of a motor vehicle internal combustion engine.

18 citations


Patent
15 Dec 2005
TL;DR: In this paper, a volumetric flow sensor and a densiometer are used to measure a mass flow rate of the fuel and a temperature sensor is also located on the circuit chip to provide accurate temperature of fuel to correspond to the fuel density reading.
Abstract: A fuel delivery system uses a volumetric flow sensor and a densiometer to measure a mass flow rate of the fuel. A densiometer may be a coriolis mass flow sensor etched into a small circuit chip. As fuel flows past the densiometer a density of the fuel and characteristic slope as a function of temperature is determined. At least one temperature sensor is also located on the circuit chip to provide accurate temperature of the fuel to correspond to the fuel density reading. Piezoelectric crystals in the volumetric flow sensor generate and receive a sound wave. By analyzing the sound wave signals the volumetric flow rate of fluid through the volumetric flow sensor can be calculated. At least one temperature sensor is also placed on the volumetric flow sensor to correct for any thermal expansion of an inner diameter of the volumetric flow sensor and for final mass flow calculation. The density and temperature information from the densiometer and the volumetric flow and temperature information from the volumetric flow sensor are used to determine the density of the fuel at the volumetric flow sensor. By using the density calculated at the volumetric flow sensor and using the volumetric flow information an accurate mass flow rate of the fuel at the volumetric flow sensor can be calculated.

Patent
22 Nov 2005
TL;DR: In this paper, a thermal sensor tube has a thermal sensing portion that is mounted relative to the sensor receiving surface in a direction substantially perpendicular to both the primary flow path and the receiving surface.
Abstract: A thermal mass flow meter for measuring flow rate of a fluid includes a conduit that is configured to receive the fluid and that defines a primary flow path between an inlet and an outlet of the conduit. The conduit is bound at least in part by a sensor receiving surface. A thermal sensor tube has a thermal sensing portion that is mounted relative to the sensor receiving surface in a direction substantially perpendicular to both the primary flow path and the sensor receiving surface. When the thermal mass flow meter is mounted in a vertical direction so that fluid within the conduit flows in the vertical direction along the primary flow path, fluid within the sensor tube flows in a horizontal direction so as to substantially prevent thermal siphoning when the sensor tube is heated.

Patent
22 Sep 2005
TL;DR: In this paper, the authors use mass gas flow metering to detect leaks in a heat exchanger, where a regulated gas supply passes through a mass flow meter before entering either the product chamber or media chamber.
Abstract: Apparatus and methods for detecting leaks in a heat exchangers use mass gas flow metering. A regulated gas supply passes through a mass flow meter before entering either the product chamber or media chamber of a heat exchanger. The regulated gas supply passes into the heat exchanger through an inlet connection. All other inlets and outlets to the testing chamber are closed and isolated so that the chamber holds an applied pressure. The chamber on the opposite side of the heat exchanger is opened to atmosphere. Once gas fills the chamber and a static pressure is realized, the test begins by simply monitoring gas flow. If no flow is indicated, no flow rate is detected, and there is no detectable leak. Gas flow into the test chamber, at any given flow rate, as sensed by the sensitive mass flow meter, is an indication that leakage between the chambers exists.

Patent
14 Dec 2005
TL;DR: In this article, an ultrasonic flow meter for measuring a flow velocity of a fluid flowing in an essentially laminar flow in the main flow direction is described, where the ultrasonic transducers are able to emit and/or receive ultrasonic waves at an angle α, which is different from 90°.
Abstract: Measuring volume flows or mass flows in the intake system of motor vehicle internal combustion engines plays an important role in reducing harmful emissions. Therefore, an ultrasonic flow meter for measuring a flow velocity of a fluid flowing in an essentially laminar flow in the main flow direction is described. The ultrasonic flow meter has at least two ultrasonic transducers, the ultrasonic transducers being able to emit and/or receive ultrasonic waves at an angle α to the main flow direction which is different from 90°. Furthermore, the ultrasonic flow meter has at least one turbulator situated upstream from at least one ultrasonic transducer in the main flow direction of the fluid, which generates longitudinal eddies in at least one zone adjacent to the at least one ultrasonic transducer, in particular in a protrusion in a wall of a flow pipe and thus improves the flow of the fluid in this zone in the flow pipe. Wedge-shaped turbulators protruding into the flow of the fluid or flow grooves are provided in particular as turbulators. The ultrasonic flow meter is distinguished, in comparison with devices known from the related art, by improved signal-to-noise ratio and thus by higher measurement accuracy.

Patent
01 Mar 2005
TL;DR: In this paper, an ultrasonic flow meter has been adapted for such measurements in the submarine environment, where two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube can measure both forward and reverse fluid flows in real time.
Abstract: An ultrasonic flow meter has been adapted for such measurements in the submarine environment. Connected to a collection funnel, the meter houses two piezoelectric transducers mounted at opposite ends of a cylindrical flow tube. By monitoring the perturbations of fluid flow on the propagation of sound waves inside the flow tube, the ultrasonic meter can measure both forward and reverse fluid flows in real time. Laboratory and field calibrations show that the ultrasonic meter can resolve groundwater discharges in both the forward and reverse directions on the order of 0.1 μm/s (<1 cm/d), and it is sufficiently robust for deployment in the field for several days. Data collected with the meter elucidate the temporal and spatial heterogeneity of submarine groundwater discharge and its interplay with tidal loading and other driving forces. A negative correlation between the discharge and tidal elevation can be observed.

Journal ArticleDOI
TL;DR: The largest problem users have with Coriolis flow meters is that they are sensitive to two phase fluids-primarily gas in liquids ('aeration'), which can convey the wrong mass flow and/or density reading, or, in the worst case, stop measuring all together as discussed by the authors.
Abstract: The largest problem users have with Coriolis flow meters is that they are sensitive to two phase fluids-primarily gas in liquids ('aeration'). 'Sensitive' means that they can convey the wrong mass flow and/or density reading, or, in the worst case, they could stop measuring all together. We explain this phenomenon in classical U-tube meters and give recommendations on how to handle such applications.

Journal ArticleDOI
TL;DR: In this article, the Coriolis dynamic response of flow meters is investigated theoretically and experimentally, by finite element simulation (complex flow tube shapes) and by experimentally using a simple straight tube.
Abstract: The dynamic response of flow meters is significant in many applications, including fast control operations, e.g. short duration (less than 1 s) batch filling and for tracking the periodic flow fluctuations produced by positive displacement devices. The factors which determine Coriolis dynamic response have been elucidated. It has been shown that the meter flow tube response time cannot be less than the duration of one drive cycle of the tube vibration (i.e. reciprocal of drive frequency). This gives the potential of a response time of order 1 ms for the fastest currently available meters. However, the delay-time and update rates from the user output depend upon flow transmitter technology and design. Flow tube dynamic response has been investigated theoretically (simple straight tube), by finite element simulation (complex flow tube shapes) and experimentally. Commercially available meters were tested to determine the flow tube dynamic response to step changes in flow rate and the response to low frequency (compared with meter drive frequency) flow pulsations. Generally, dynamic flow events have been found to introduce contaminating signal components at one or more frequencies, other than that of the meter drive. The paper also presents details of the signal processing used to extract the required phase-difference and a method for reducing the contaminating signal noise. A new fast-response meter is currently being developed and some of the significant advances in the technology of a novel digital transmitter are described.

Patent
12 May 2005
TL;DR: In this paper, a dynamic heat flow meter is provided which introduces a measured air flow into the system adjacent the test sample (e.g., insulation product), for which thermal properties are to be measured.
Abstract: A dynamic heat flow meter is provided which introduces a measured air flow into the system adjacent the test sample (e.g., insulation product), for which thermal properties are to be measured. The heat flow meter then measures thermal properties (e.g., thermal conductivity and/or heat capacity) of the test sample taking into account air flow through and/or adjacent the test sample.

Patent
19 Jul 2005
TL;DR: In this article, a housing structure for improving air flow to the intake manifold of an internal combustion engine is proposed, which allows for larger air flow through the housing through the use of a bypass air passage or calibration tube that reduces air flow as experienced by the mass air flow sensor.
Abstract: A housing structure for improving air flow to the intake manifold of an internal combustion engine is claimed. The present invention is a replacement part for a factory-installed mass air flow sensor housing and is designed to allow for larger air flow through the housing through the use of a bypass air passage or calibration tube that reduces air flow as experienced by the mass air flow sensor. The calibration tube reduces air flow across the sensor with a larger bore on its inlet and a restriction in its outlet. The calibration tube is angled to reduce back flow from the engine.

Patent
14 Feb 2005
TL;DR: In this article, the Coriolis principle was used to define the first flow meter and the second flow meter, and the first and second flow meters were disposed in a common housing.
Abstract: A device having a first flow meter ( 2 ) and a second flow meter ( 3 ). The first and the second flow meters work according to a Coriolis principle. The first flow meter includes a first measuring tube ( 7 ). The second flow meter includes a second measuring tube ( 10 ). The first flow meter and the second flow meter are disposed in a common housing ( 4,5,6 ). The first flow meter and the second flow meters have different eigenfrequencies because of a first vibration-influencing device ( 18 ) attached to the first flow meter and a second vibration-influencing device ( 19 ) attached to the second flow meter.

Patent
Andreas Wildgen1
18 Feb 2005
TL;DR: In this article, a mass flow sensor is provided which is arranged in a recess in a body and which is coupled via a coupling element to the main duct (4), with the coupling element being embodied in such a way that the recess lies in the wind shadow of the main direction of flow of the mass flow in a main duct and brings about a flow in the recess counter.
Abstract: A mass flow sensor ( 1 ) has a sensor element whose measuring signal is representative of a mass flow in a main duct ( 4 ), specifically without taking into account the direction of flow of the mass flow which flows past the sensor element. In addition, a further sensor element is provided which is arranged in a recess in a body and which is coupled via a coupling element to the main duct ( 4 ), with the coupling element being embodied in such a way that the recess lies in the wind shadow of the main direction of flow of the mass flow in the main duct ( 4 ) and brings about a flow in the recess counter to the main direction of flow. A mass current is determined in the main duct ( 4 ) as a function of the measuring signal of the sensor element. A correction value is determined as a function of the measuring signal of the further sensor element. The mass flow which is determined is corrected by means of the correction value.

Journal ArticleDOI
TL;DR: In this paper, the effect of cone swirler flow conditioner for both standard and non-standard flow conditions has been carried out in the experimental rig and the measuring of mass flow rate under different conditions and different Reynolds numbers were used to establish a change in discharge coefficient relative to a standard one.
Abstract: Purpose – The sensitivity of orifice plate metering to poorly conditioned and swirling flows are subjects of concerns to flow meter users and manufacturers. The distortions caused by pipe fittings and pipe installations upstream of the orifice plate are major sources of this type of non‐standard flows. These distortions will alter the accuracy of metering up to an unacceptable degree.Design/methodology/approach – The design of orifice plate meters that are independent of the initial flow conditions of the upstream is a major object of flow metering. Either using a long straight pipe or a flow conditioner upstream of an orifice plate usually achieves this goal. The effect of cone swirler flow conditioner for both standard and non‐standard flow conditions has been carried out in the experimental rig. The measuring of mass flow rate under different conditions and different Reynolds numbers were used to establish a change in discharge coefficient relative to a standard one.Findings – The experimental results ...

Patent
17 Mar 2005
TL;DR: In this article, a fluid flow sensor assembly comprised of a flow sensor plumbed to convey flow in parallel with a normally closed, high-flow valve, displaceable to an opened position in response to hydrodynamic force, for placement into a fluid conduit to achieve a precise measurement of the fluid volumetric flow with a high turndown ratio at a pressure drop below which the flow sensor alone would impose, is disclosed.
Abstract: A fluid flow sensor assembly comprised of a fluid flow sensor plumbed to convey flow in parallel with a normally-closed, high-flow valve, displaceable to an opened position in response to hydrodynamic force, for placement into a fluid conduit to achieve a precise measurement of the fluid volumetric flow with a high turndown ratio at a pressure drop below which the flow sensor alone would impose, is disclosed. In addition, the mathematic relationship of the flow sensor output to the fluid volumetric flow rate through the parallel flow sensor assembly, throughout the flow range, is disclosed.

Journal ArticleDOI
TL;DR: In this paper, a new generation of liquid flow sensors that is capable of meeting the requirements as imposed by the life science, analysis, biotech and other markets is presented, using tubes made of silica, stainless steel or PEEK.
Abstract: Purpose – To present a new generation of liquid flow sensors that is capable of meeting the requirements as imposed by the life science, analysis, biotech and other marketsDesign/methodology/approach – A description of the design and development of low flow rate measuring system and typical applicationsFindings – The system described uses tubes made of silica, stainless steel or PEEK, and either constant power or constant temperature methods in conjunction with a heater and temperature sensor The tested instruments were capable of measuring flow ranges between 25‐500 nl/min (smallest flow range) and 100‐2000 μl/min (largest flow range) water, with operating pressures up to 100 bar (up to 400 bar for flow meters with flow ranges below 100 μl/min)Originality/value – Presents information on a new generation of liquid flow sensors


Patent
26 Jan 2005
TL;DR: In this paper, the authors proposed a flow meter consisting of a water content meter and a double differential pressure generating and measuring structure that provides two measurement signals 6A-B representing two independent values of differential pressure (DP) in said fluid.
Abstract: A flow meter obtains the individual flow rates of gas, liquid hydrocarbons and water in a predominantly gas-containing fluid flowing mixture. The flow meter comprises a water content meter 7 providing a signal representing a measure of the water content of said fluid 1. It also comprises a double differential pressure generating 3 and measuring 4 structure that provides two measurement signals 6A-B representing two independent values of differential pressure (DP) in said fluid 1. In addition to the above, the meter also comprises a signal processing unit 8 having inputs 9A-C for receiving the measurement signals 6A-B and the water content signal 13, and a calculation module 10 which calculates values representing the volumetric flow rates of said gas, liquid hydrocarbons and water in said fluid 1.

Journal ArticleDOI
TL;DR: In this article, the design of the fan-beam optical sensor including spatial arrangement of the structural parts, basic principle and measurement sensitivity distribution are introduced, and the mathematical measurement model of solid mass flow rate is presented together with the testing results.
Abstract: The fan-beam optical sensor is made up of many semiconductor lasers and detectors fixed around the wall alternately at a cross section of pneumatically conveying pipe. When the sensor works, a scanning light source emits a 50° lamellar fan-beam through the gas-solid two phase flow, and the projection data resulting extinction effect of solid particles are detected at the same time. With the projection data, the flow rate mass can be calculated, and then the flow image can be reconstructed. In this paper, the design of the sensor including spatial arrangement of the structural parts, basic principle and measurement sensitivity distribution are introduced. The mathematical measurement model of solid mass flow rate is presented together with the testing results.

Patent
02 Nov 2005
TL;DR: In this paper, a method for calculating the mass flow rate of a cryogenic fluid within a flow tube is proposed, which involves positioning a sensor within a stream of cryogenic liquid flowing through the flow tube.
Abstract: A method for calculating a mass flow rate of a cryogenic fluid within a flow tube includes positioning a sensor within a stream of cryogenic fluid flowing through the flow tube. The sensor is operatively coupled to a strain gauge. A difference between a dynamic pressure in the fluid stream and a static pressure in the fluid stream is measured and the mass flow rate of the cryogenic fluid within the flow tube is calculated.


Patent
02 Dec 2005
TL;DR: In this article, a hot-film air mass sensor was used to measure the air mass flow of an internal combustion engine by an application of a hot film sensor, and a gradient field producing device was formed in order to produce an electric field with a field gradient.
Abstract: The sensor has a sensor surface that is overflowable by air mass flow, and a gradient field producing device (134) that is formed in order to produce an electric field (148) with a field gradient. The electric field that is produced by the device (134) partially penetrates the air mass flow. The air mass flow flows in a mainstream direction, and the electric field runs perpendicular to the mainstream direction. The gradient field producing device exhibits a condenser (138), which includes large electrode (140) and small electrode (142). An independent claim is also included for a method for measuring an air mass flow of an internal combustion engine by an application of a hot-film air mass sensor.