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Design of ASR Systems
Published in R. David, G. Pyne, Groundwater Recharge and Wells, 2017
Ultrasonic flowmeters are portable, and can be moved easily from one length of pipe to another. The meter mounts to the outside of an existing pipe and requires no moving or other parts in the water flow stream. They operate by electronically measuring the time required for an ultrasonic signal to travel between two or three transducers mounted to the outside of the pipe. The difference in time between signals traveling upstream and downstream is proportional to the liquid velocity. The meters usually consist of several transducers that can be mounted in several configurations and record to a data-logging microprocessor. Pipe material, diameter, wall thickness, and lining type and thickness must be known and entered into the microprocessor. Ultrasonic flowmeters are well suited for checking the performance and accuracy of inline meters and can be obtained with an accuracy of ±1% of the actual flow rate.
The Paradigm Case Method of Selecting Flowmeters
Published in Jesse Yoder, New-Technology Flowmeters, 2023
Transit time ultrasonic meters have both a sender and a receiver. They send an ultrasonic signal across a pipe at an angle and measure the time it takes for the signal to travel from one side of the pipe to the other. When the ultrasonic signal travels with the flow, it travels faster than when it travels against the flow. The ultrasonic flowmeter determines how long it takes for the signal to cross the pipe in one direction, and then determines how long it takes the signal to cross the pipe in the reverse direction. The difference between these times is proportional to flowrate. Transit time ultrasonic flowmeters are mainly used for clean liquids.
Acoustic Sensors
Published in J. David, N. Cheeke, Fundamentals and Applications of Ultrasonic Waves, 2017
There are many ways of measuring flow in liquids and gases. These include variable differential pressure across an orifice (flow nozzle, Venturi, Pitot tube, etc.), Coriolis, oscillatory method, displacement, thermal, magnetic, and ultrasonic. Ultrasonic flow meters have one important advantage over all others in that they can be noninvasive, for example, clamped on the outside of a pipe in an existing system. They also have excellent long-term stability, low power consumption, and low capital cost.
Investigation of flow characteristics downstream vertical sluice gates of Bahr Yousef regulator physical model
Published in Water Science, 2023
Mohamed A. Eizeldin, Abdelazim M. Ali, AMIRA S. Farag
A well-designed 2D hydraulic physical detail model for one bay of Bahr Yousef regulator was used. The model was constructed inside double glasses rectangular Flume with dimension of 26 m long, 1.0 m wide, and 1.2 m high. The side walls along the entire length of the flume were made of glass with steel-frames, to allow visual investigation of the flow patterns and stability of bed protection. The stilling basin of the model is made of smooth wood and the two half piers are made of plexiglass which gives a good monitoring for the flow along the entire length of the model. The maximum feeding capacity of the system is 0.4 m3/s (400 l/s). The ultrasonic flowmeter is installed on 16 inch-diameter flow pipes to measure the discharge. The ultrasonic flowmeter has an accuracy of ±1%. The model bottom in the flume is shaped with sand overlain by riprap in upstream and downstream reaches, as shown in Figures 2, 3, and 4. For correct reproduction of the important hydraulic phenomena in a hydraulic model, a complete similarity including geometric and dynamic similarity between prototype and model must be fulfilled when determining the model scales. Because the model has free surface flow, the inertia and gravitational forces are dominant. Therefore, for simulation, the model has to be based on Froude similarity. To simulate the kinematics and dynamics of the flow field properly, an undistorted geometric scale model is required. The Froude number, which represents the ratio of flow inertia forces to gravitational forces, is given by eq. (1):