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Would you like to change to the site? This is a dummy description.This is a dummy description.This is a dummy description.This is a dummy description.An Introductory Guide to Flow Measurement is an indispensable guide for the busy practising engineer. It provides a ready source of information on flowmeters, their operation, installation, and relative advantages and disadvantages in different applications. This revised edition retains the succinct style of the original, with plenty of clear line diagrams and shading to highlight key points, it is comprehensive and easy-to-use. The material is based on the author’s own lectures at Cranfield Institute of Technology, UK, but incorporates lessons learned through using the first edition as a teaching tool during the 13 years since its first publication. It aims to transmit as much information as possible, as efficiently as possible, in as short a time as possible. Existing and new readers alike will welcome this updated version of the well established and highly regarded Introductory Guide to Flow Measurement. Key areas considered include, Accuracy; flow behavior, and fluid parameters Calibration techniques Selection Momentum flowmeters Volumetric flowmeters Mass flowmeters Probes and tracers Recent developments and future trends Having held teaching posts at Cambridge University and Imperial College, he was Professor of Fluid Engineering at Cranfield for 12 years, setting up and running the Department of Fluid Engineering and Instrumentation. He has worked closely with industry in the UK and the USA. He has now returned to Cambridge and is working full-time there as a Visiting Industrial Fellow, while retainng his links with Cranfield through his Visiting Professorship there. The 13-digit and 10-digit formats both work. Please try again.Please try again.Please try again. Additional terms apply.We'll e-mail you with an estimated delivery date as soon as we have more information.http://fire-matic.com/testingsites/advantage_aviation/assets/media/advanced-accounting-2-guerrero-solutions-manual.xml
Your account will only be charged when we ship the item. The previous editions of this book have been widely used for over 13 years. In this new edition, the author retains the succinctness of the earlier books by removing material that was of marginal value, and by referring readers who require more detailed information to other resources. This first U.S. edition, published by ASME Press, includes, ASME Code references, which were not included in previous British editions of the book. Then you can start reading Kindle books on your smartphone, tablet, or computer - no Kindle device required. Register a free business account Full content visible, double tap to read brief content. Videos Help others learn more about this product by uploading a video. Upload video To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzes reviews to verify trustworthiness. Please try again later. Amazon Customer 5.0 out of 5 stars. Groups Discussions Quotes Ask the Author To see what your friends thought of this book,This book is not yet featured on Listopia.There are no discussion topics on this book yet. By using our website you agree to our use of cookies. This revised edition retains the succinct style of the original, with plenty of clear line diagrams and shading to highlight key points, it is comprehensive and easy to use. The material is based on the author's own lectures at Cranfield Institute of Technology, UK, but incorporates lessons learned through using the first edition as a teaching tool during the 13 years since its first publication. It aims to transmit as much information as possible, as efficiently as possible, in as short a time as possible.http://www.eventing.hu/userfiles/advanced-accounting-11e-solutions-manual.xml
Essential reading for any engineer faced with a flow measurement problem this book will enable the reader to assess advice received from manufacturers and contribute to discussions with experts. Key areas considered include: Accuracy (flow behavior, and fluid parameters); Calibration techniques; Selection; Momentum flowmeters; Volumetric flowmeters; Mass flowmeters; Probes and tracers; and, Recent developments and future trends. show more Part 2 Calibration: datum conditions; steady flow; calibration rigs for liquids; calibration rigs for gases; master meters; site calibrations; general comments. Part 3 Selection: considerations in selecting a flowmeter; nature of the fluid to be metered; flowmeter constraints; environment; special effects; price; choosing. Part 4 Momentum flowmeters: orifice plate meter; Venturi meter; special orifice plates and flow nozzles; critical nozzle (sonic nozzle); other differential pressure devices; target meter (drag plate); variable area, Rotameter (R) or float-in-tube meter; momentum-sensing flowmeters - general comments. Part 5 Volumetric flowmeters: positive displacement meters; turbine meters; oscillatory meters; electromagnetic meters; ultrasonic meters. Part 6 Mass flowmeters: introduction; thermal mass flow measurement; angular momentum fuel flowmeter; Coriolis flowmeters. Part 7 Probes and tracers: probes; averaging pitot; tracers; conclusions. Part 8 Recent developments and likely future trends in flow measurement: instruments; meters for multiphase flow; developing technologies; manufacture and management; conclusions. show more Having held teaching posts at Cambridge University and Imperial College, he was Professor of Fluid Engineering at Cranfield for 12 years, setting up and running the Department of Fluid Engineering and Instrumentation. He has worked closely with industry in the UK and the USA.
He has now returned to Cambridge and is working full-time there as a Visiting Industrial Fellow, while retainng his links with Cranfield through his Visiting Professorship there. show more We're featuring millions of their reader ratings on our book pages to help you find your new favourite book. An Introductory Guide to Flow Measurement is an indispensable guide for the busy practising engineer. It provides a ready source of information on flowmeters, their operation, installation, and relative advantages and disadvantages in different applications. This revised edition retains the succinct style of the original, with plenty of clear line diagrams and shading to highlight key points, it is comprehensive and easy-to-use. The material is based on the author's own lectures at Cranfield Institute of Technology, UK, but incorporates lessons learned through using the first edition as a teaching tool during the 13 years since its first publication. It aims to transmit as much information as possible, as efficiently as possible, in as short a time as possible. Essential reading for any engineer faced with a flow measurement problem - this book will enable the reader to assess advice received from manufacturers and contribute to discussions with experts. Existing and new readers alike will welcome this updated version of the well established and highly regarded Introductory Guide to Flow Measurement. Key areas considered include, Accuracy; flow behavior, and fluid parameters Calibration techniques Selection Momentum flowmeters Volumetric flowmeters Mass flowmeters Probes and tracers Recent developments and future trends Sammen med vores kunder og UNICEF gor vi en indsats for, at alle verdens born skal l?re at l?se. Vi vil gore det sa nemt som muligt for dig at l?se, lytte til og udgive boger i alle afskygninger - fra forfatteren fa?r sin forste ide? til du som l?ser vender den sidste side. L?s Lyt Lev. Du kan altid afmelde dig nyhedsbrevet. Vi behandler dine person- og pr?
ferenceoplysninger for at kunne sende dig nyhedsbrevet. L?s mere i persondatapolitikken. Du bestemmer selv, og vores kundeservice sidder altid klar med hj?lp. Medlemskabet fornyes automatisk, og du kan altid opsige det. The previous editions of this book have been widely used for over 13 years. In this new edition, the author retains the succinctness of the earlier books, by removing material which was of marginal value, and by referring readers who require more detailed information to other resources. The first U.S. edition, published by ASME Press, includes ASME Code references, which were not included in previous British editions of the book. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Temporibus autem quibusdam et aut officiis debitis aut rerum necessitatibus saepe eveniet ut et voluptates repudiandae sint et molestiae non recusandae. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat. Flow can be measured in a variety of ways. The common types of flowmeters with industrial applications are listed below:Flow may be measured by measuring the velocity of fluid over a known area. For very large flows, tracer methods may be used to deduce the flow rate from the change in concentration of a dye or radioisotope.These measurements are related by the material's density. The density of a liquid is almost independent of conditions. This is not the case for gases, the densities of which depend greatly upon pressure, temperature and to a lesser extent, composition.The energy flow rate is the volumetric flow rate multiplied by the energy content per unit volume or mass flow rate multiplied by the energy content per unit mass.
Energy flow rate is usually derived from mass or volumetric flow rate by the use of a flow computer.A volume of gas under one set of pressure and temperature conditions is not equivalent to the same gas under different conditions.For example, an orifice plate produces a pressure drop that is a function of the square of the volume rate of flow through the orifice. A vortex meter primary flow element produces a series of oscillations of pressure. Generally, the physical property generated by the primary flow element is more convenient to measure than the flow itself.The stopwatch is started when the flow starts and stopped when the bucket reaches its limit. The volume divided by the time gives the flow rate. For continuous measurements, we need a system of continually filling and emptying buckets to divide the flow without letting it out of the pipe. These continuously forming and collapsing volumetric displacements may take the form of pistons reciprocating in cylinders, gear teeth mating against the internal wall of a meter or through a progressive cavity created by rotating oval gears or a helical screw.For each rotation, an amount of water passes through the piston chamber. Through a gear mechanism and, sometimes, a magnetic drive, a needle dial and odometer type display are advanced.Fluid forces the meshed gears to rotate; each rotation corresponds to a fixed volume of fluid. Counting the revolutions totalizes volume, and the rate is proportional to flow. Such a meter has two sides, which can be called A and B. No fluid passes through the center of the meter, where the teeth of the two gears always mesh. On one side of the meter (A), the teeth of the gears close off the fluid flow because the elongated gear on side A is protruding into the measurement chamber, while on the other side of the meter (B), a cavity holds a fixed volume of fluid in a measurement chamber.
As the fluid pushes the gears, it rotates them, allowing the fluid in the measurement chamber on side B to be released into the outlet port. Meanwhile, fluid entering the inlet port will be driven into the measurement chamber of side A, which is now open. The teeth on side B will now close off the fluid from entering side B. This cycle continues as the gears rotate and fluid is metered through alternating measurement chambers. Permanent magnets in the rotating gears can transmit a signal to an electric reed switch or current transducer for flow measurement.These openings divide up the fluid stream and as the gears rotate away from the inlet port, the meter's inner wall closes off the chamber to hold the fixed amount of fluid. The outlet port is located in the area where the gears are coming back together. The fluid is forced out of the meter as the gear teeth mesh and reduce the available pockets to nearly zero volume.These rotors resemble the shape of a helix, which is a spiral-shaped structure. As the fluid flows through the meter, it enters the compartments in the rotors, causing the rotors to rotate. The length of the rotor is sufficient that the inlet and outlet are always separated from each other thus blocking a free flow of liquid. The mating helical rotors create a progressive cavity which opens to admit fluid, seals itself off and then opens up to the downstream side to release the fluid. This happens in a continuous fashion and the flowrate is calculated from the speed of rotation.The fluid, most commonly water, enters in one side of the meter and strikes the nutating disk, which is eccentrically mounted. A partition separates the inlet and outlet chambers. As the disk nutates, it gives direct indication of the volume of the liquid that has passed through the meter as volumetric flow is indicated by a gearing and register arrangement, which is connected to the disk.
The flowing fluid impinges on the turbine blades, imparting a force to the blade surface and setting the rotor in motion. When a steady rotation speed has been reached, the speed is proportional to fluid velocity. The flow direction is generally straight through the meter, allowing for higher flow rates and less pressure loss than displacement-type meters. They are the meter of choice for large commercial users, fire protection, and as master meters for the water distribution system. Strainers are generally required to be installed in front of the meter to protect the measuring element from gravel or other debris that could enter the water distribution system. Turbine meter bodies are commonly made of bronze, cast Iron, or ductile iron. Internal turbine elements can be plastic or non-corrosive metal alloys. They are accurate in normal working conditions but are greatly affected by the flow profile and fluid conditions.Portable turbine meters may be temporarily installed to measure water used from a fire hydrant. The meters are normally made of aluminum to be lightweight, and are usually 7.5 cm (3 in) capacity. Water utilities often require them for measurement of water used in construction, pool filling, or where a permanent meter is not yet installed.They are increasing in popularity in the UK at larger sizes and are commonplace in the EU.Magnets in the paddle spin past the sensor. The electrical pulses produced are proportional to the rate of flow. As the magnets in the blades spin past the sensor, the paddle wheel meter generates a frequency and voltage signal which is proportional to the flow rate. The faster the flow the higher the frequency and the voltage output. These are available with wide range of fittings styles, connection methods and materials such as PVDF, polypropylene, and stainless steel.The processed signal can be used to control the process, generate an alarm, send signals to external etc.
The impeller element is in a housing in which multiple inlet ports direct the fluid flow at the impeller causing it to rotate in a specific direction in proportion to the flow velocity. This meter works mechanically much like a single jet meter except that the ports direct the flow at the impeller equally from several points around the circumference of the element, not just one point; this minimizes uneven wear on the impeller and its shaft. Thus these types of meters are recommended to be installed horizontally with its roller index pointing skywards.Propeller-type current meters (similar to the purely mechanical Ekman current meter, but now with electronic data acquisition) can be traversed over the area of the penstock and velocities averaged to calculate total flow. This may be on the order of hundreds of cubic meters per second. The flow must be kept steady during the traverse of the current meters. Methods for testing hydroelectric turbines are given in IEC standard 41. Such flow measurements are often commercially important when testing the efficiency of large turbines.This method is widely used to measure flow rate in the transmission of gas through pipelines, and has been used since Roman Empire times.It is basically a crude form of Venturi meter, but with higher energy losses.As with these flowmeters the flow rate in a Dall tube is determined by measuring the pressure drop caused by restriction in the conduit. The pressure differential is typically measured using diaphragm pressure transducers with digital readout. Since these meters have significantly lower permanent pressure losses than orifice meters, Dall tubes are widely used for measuring the flow rate of large pipeworks. Differential pressure produced by a Dall tube is higher than Venturi tube and nozzle, all of them having same throat diameters.
The tube is pointed into the flow and the difference between the stagnation pressure at the tip of the probe and the static pressure at its side is measured, yielding the dynamic pressure from which the fluid velocity is calculated using Bernoulli's equation.A typical impact probe consists of three or more holes (depending on the type of probe) on the measuring tip arranged in a specific pattern. More holes allow the instrument to measure the direction of the flow velocity in addition to its magnitude (after appropriate calibration). Three holes arranged in a line allow the pressure probes to measure the velocity vector in two dimensions.The cone meter is a generic yet robust differential pressure (DP) meter that has shown to be resistant to effects of asymmetric and swirling flow. Because cone meters are generally of welded construction, it is recommended they are always calibrated prior to service. Inevitably heat effects of welding cause distortions and other effects that prevent tabular data on discharge coefficients with respect to line size, beta ratio and operating Reynolds numbers from being collected and published.Such flow is called viscous drag flow or laminar flow, as opposed to the turbulent flow measured by orifice plates, Venturis and other meters mentioned in this section, and is characterized by Reynolds numbers below 2000. The primary flow element may consist of a single long capillary tube, a bundle of such tubes, or a long porous plug; such low flows create small pressure differentials but longer flow elements create higher, more easily measured differentials.A kind of rotameter used for medical gases is the Thorpe tube flowmeter. Floats are made in many different shapes, with spheres and spherical ellipses being the most common. Some are designed to spin visibly in the fluid stream to aid the user in determining whether the float is stuck or not. Rotameters are available for a wide range of liquids but are most commonly used with water or air.
They can be made to reliably measure flow down to 1% accuracy.Small particles which accompany natural and industrial gases pass through two laser beams focused a short distance apart in the flow path in a pipe by illuminating optics. Laser light is scattered when a particle crosses the first beam. The detecting optics collects scattered light on a photodetector, which then generates a pulse signal. As the same particle crosses the second beam, the detecting optics collect scattered light on a second photodetector, which converts the incoming light into a second electrical pulse. By measuring the time interval between these pulses, the gas velocity is calculated as The operating principle enables optical laser technology to deliver highly accurate flow data, even in challenging environments which may include high temperature, low flow rates, high pressure, high humidity, pipe vibration and acoustic noise.Because distance between the two laser sheets does not change, optical flowmeters do not require periodic calibration after their initial commissioning. Optical flowmeters require only one installation point, instead of the two installation points typically required by other types of meters. A single installation point is simpler, requires less maintenance and is less prone to errors.Techniques appropriate for a fixed cross-section of flow in a pipe are not useful in open channels. Measuring flow in waterways is an important open-channel flow application; such installations are known as stream gauges.This depth is converted to a flow rate according to a theoretical formula of the form Level to flow devices are commonly used to measure the flow of surface waters (springs, streams, and rivers), industrial discharges, and sewage.Velocity times the cross-sectional area yields a flow rate which can be integrated into volumetric flow. There are two types of area velocity flowmeter: (1) wetted; and (2) non-contact.
Wetted area velocity sensors have to be typically mounted on the bottom of a channel or river and use Doppler to measure the velocity of the entrained particles. With depth and a programmed cross-section this can then provide discharge flow measurement. Non-contact devices that use laser or radar are mounted above the channel and measure the velocity from above and then use ultrasound to measure the depth of the water from above.After complete mixing, the concentration is measured. The dilution rate equals the flow rate.The fluid temperature is also measured and compensated for. If the density and specific heat characteristics of the fluid are constant, the meter can provide a direct mass flow readout, and does not need any additional pressure temperature compensation over their specified range.In fact, most gases can be measured as long as they are fairly clean and non-corrosive. For more aggressive gases, the meter may be made out of special alloys (e.g. Hastelloy ), and pre-drying the gas also helps to minimize corrosion.Many such mass flow sensors use a heated element and a downstream temperature sensor to indicate the air flowrate. Other sensors use a spring-loaded vane. In either case, the vehicle's electronic control unit interprets the sensor signals as a real-time indication of an engine's fuel requirement.As the fluid passes this bar, disturbances in the flow called vortices are created. The vortices trail behind the cylinder, alternatively from each side of the bluff body. This vortex trail is called the Von Karman vortex street after von Karman's 1912 mathematical description of the phenomenon. The frequency at which these vortices alternate sides is essentially proportional to the flow rate of the fluid. Inside, atop, or downstream of the shedder bar is a sensor for measuring the frequency of the vortex shedding. This sensor is often a piezoelectric crystal, which produces a small, but measurable, voltage pulse every time a vortex is created.
Since the frequency of such a voltage pulse is also proportional to the fluid velocity, a volumetric flow rate is calculated using the cross-sectional area of the flowmeter. The frequency is measured and the flow rate is calculated by the flowmeter electronics using the equation Sonar flowmeters have been widely adopted in mining, metals processing, and upstream oil and gas industries where traditional technologies have certain limitations due to their tolerance to various flow regimes and turn down ratios.The principle behind this flow measurement is the use of underwater acoustics.The physical principle at work is Faraday's law of electromagnetic induction. The magnetic flowmeter requires a conducting fluid and a nonconducting pipe liner. The electrodes must not corrode in contact with the process fluid; some magnetic flowmeters have auxiliary transducers installed to clean the electrodes in place. The applied magnetic field is pulsed, which allows the flowmeter to cancel out the effect of stray voltage in the piping system.An LFF measures the integrated or bulk Lorentz force resulting from the interaction between a liquid metal in motion and an applied magnetic field. In this case, the characteristic length of the magnetic field is of the same order of magnitude as the dimensions of the channel. It must be addressed that in the case where localized magnetic fields are used, it is possible to perform local velocity measurements and thus the term Lorentz force velocimeter is used.While they both utilize ultrasound to make measurements and can be non-invasive (measure flow from outside the tube, pipe or vessel), they measure flow by very different methods.This time difference is a measure for the average velocity of the fluid along the path of the ultrasonic beam. By using the absolute transit times both the averaged fluid velocity and the speed of sound can be calculated.
Using the two transit times The frequency of the transmitted beam is affected by the movement of the particles; this frequency shift can be used to calculate the fluid velocity. For the Doppler principle to work, there must be a high enough density of sonically reflective materials such as solid particles or air bubbles suspended in the fluid. This is in direct contrast to an ultrasonic transit time flowmeter, where bubbles and solid particles reduce the accuracy of the measurement. Due to the dependency on these particles, there are limited applications for Doppler flowmeters. This technology is also known as acoustic Doppler velocimetry.A drop in quality (change in the measured speed of sound) is an indication that the meter needs servicing.A laser Doppler velocimeter (LDV), also called a laser Doppler anemometer (LDA), focuses a laser beam into a small volume in a flowing fluid containing small particles (naturally occurring or induced). The particles scatter the light with a Doppler shift. Analysis of this shifted wavelength can be used to directly, and with great precision, determine the speed of the particle and thus a close approximation of the fluid velocity.All use a photodetector (typically an avalanche photodiode ) to convert the light into an electrical waveform for analysis. In most devices, the original laser light is divided into two beams. In one general LDV class, the two beams are made to intersect at their focal points where they interfere and generate a set of straight fringes. The sensor is then aligned to the flow such that the fringes are perpendicular to the flow direction. As particles pass through the fringes, the Doppler-shifted light is collected into the photodetector. In another general LDV class, one beam is used as a reference and the other is Doppler-scattered.The transit time is defined with the help of radiation detectors placed on the outside of the pipe.
The volume flow is obtained by multiplying the measured average fluid flow velocity by the inner pipe cross-section. This reference flow value is compared with the simultaneous flow value given by the flow measurement to be calibrated.A solution with a known tracer concentration is injected at a constant known velocity into the channel flow. Downstream the tracer solution is thoroughly mixed over the flow cross-section, a continuous sample is taken and its tracer concentration in relation to that of the injected solution is determined. The flow reference value is determined by using the tracer balance condition between the injected tracer flow and the diluting flow. The procedure is standardised (ISO 9555-1 and ISO 9555-2 for liquid flow in open channels).February 2006. London: IWA Publishing. p. 33. ISBN 9781843390343. September 2012. Retrieved 1 September 2019. Retrieved 14 March 2008. Retrieved 3 August 2015. Archived from the original on 28 October 2009. Retrieved 15 September 2016. CS1 maint: archived copy as title ( link ) Retrieved 15 September 2016. CS1 maint: archived copy as title ( link ) By using this site, you agree to the Terms of Use and Privacy Policy. From an introduction of basic flow principles to selecting and installing the optimal technology for your application, this extensive handbook includes all of the most essential DP flow information in one convenient place. User Guide Link All rights reserved. However, due to transit disruptions in some geographies, deliveries may be delayed.There’s no activationEasily readThis guide provides a review of basic laws and principles, an overview of physical characteristics and behavior of gases and liquids, and a look at the dynamics of flow. The authors examine applications of specific meters, readout and related devices, and proving systems.