Ultrasonic flow meter

Ultrasonic Flow Meters. Ultrasonic flow meters can be divided into three broad groups passive or turbulent noise flow meters, Doppler or frequency-shift flow meters, and transit time flow meters. 

Peripheral circulation should be monitored as soon as possible using an ultrasonic flow meter as circumferential full-thickness extremity burns may compromise distal perfusion and require escharotomy. Radial, ulnar, palmar arch, posterior tibial, and dorsalis pedis pulses should be checked hourly for progressive decrease or total loss. If necessary, escharotomies should be done in consult with a burn center to avoid severe neurologic... 

Ultrasonic Flowmeters. Ultrasonic methods have been used to measure flow velocity and concentration in slurry pipelines (22) and emulsion pipelines (65). There are three methods of ultrasonic flow meter applications transmission of ultrasonic wave, beam deflection, and frequency shift method (22). The frequency shift method (the ultrasonic Doppler flowmeter) consists of a transducer and an electronic control box. The transducer is either clamped on the outside of the pipe or inserted into the pipe so that it is flush with the inside of the pipe wall. The transducer comprises the sensors to transmit and receive the Doppler signal. These sensors are either in a single transducer or in two separate transducers. The control box processes transmitted and received signals (Figure 25). 

Time-of-flight ultrasonic flow meter single-path type. 

Time-of-flight ultrasonic flow meter multipath type. (Adapted from Miller, R. W., Flow Measurement Engineering Handbook, New York McGraw-Hill, Inc., 1989.)... 

Weir plates, flumes, elbow taps, target flow meters, ultrasonic flow meters, and positive displacement meters may be preferred under certain conditions. 

An ultrasonic flow meter allows flow measurement of water and other liquids from the outside of piping. 

A multichannel recorder capable of measuring and recording variable parameters over a period of time provides information on equipment operation as a function of a variable. Typical parameters measured include kilowatts, kWh, temperatures, and, with the use of the ultrasonic flow meter, flow. With this equipment, for example, it is possible to record chiller load and energy use as a function of outdoor air temperature by recording chilled-water supply and return temperature, chilled-water flow, chiller kilowatts, and outdoor air temperature. 

A Ultrasonic Flow Meter Reading — Power CTheoretkal)... 

Outlet Volumetric Flow The nominal volumetric flow of 0.15 m /sec (corresponding to a mass flow of 3.08 kg/sec) for the four loop non-optimized Brayton system of Section 6 is assumed. The range 0.01-1 m /sec has been selected to cover a sufficiently wide range of operation to provide for plant startup at reduced flows, full power operation, and casualty performance. The accuracy of 0.0025 m /sec typifies the accuracy of 0.25% of point found in gas industry ultrasonic flow metering equipment The time constant of 1 second typifies high precision pressure sensor with digital instrumentation. 

In research reactors that use liquid metal coolant, flow can be measured either by use or an electromagnetic flow meter or by an ultrasonic flow meter. The electromagnetic flow meter generates a voltage proportional to the coolant flow, and the ultrasonic flow meter deduce the flow by measuring the sound transmission time between the transmitting and receiving rod pairs. The accuracy of measurement in both cases is around 10%. 

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