Ultrasonic flow meters use sound waves to define the velocity of a fluid flowing in a pipe. At no flow conditions, the frequencies of an ultrasonic wave diffused into a pipe and its replications from the fluid are the same. Under flowing conditions, the frequency of the replicated wave is different due to the Doppler Effect. When the fluid moves faster, the frequency shift surges linearly. The transmitter routes signals from the transmitted wave and its reflections to regulate the flow rate.
The ultrasonic flow meters send and receive ultrasonic waves amid
transducers in both the upstream and downstream ways in the pipe. At no flow circumstances,
it takes the same time to travel upstream and downstream amongst the
transducers. In flowing settings, the upstream wave will move gentler and take
more time than the downstream wave. When the fluid moves faster, the variance
between the upstream and downstream times rises.
Ultrasonic
flow meters are usually applied to measure the velocity of liquids that permit
ultrasonic waves to pass, such as water, molten sulfur, cryogenic liquids, and
chemicals. Transit time designs are also accessible to measure gas and vapor
flow. Since fluids that do not pass ultrasonic energy, such as many types of
slurry, restrict the penetration of ultrasonic waves into the fluid. In
ultrasonic flowmeters, opaque fluids can restrict ultrasonic wave diffusion too
near the pipe wall, which can reduce accuracy and make the flowmeter to measure
wrongly. The ultrasonic flowmeters can stop functioning when an opaque fluid declines
the ultrasonic wave to such a level that the wave does not touch the receiver.
Be sure that the fluid can sufficiently
conduct ultrasonic waves, since the flow measurements will not quantity when
the ultrasonic waves cannot pierce the flow stream between the transducers. Likewise,
ultrasonic waves must be able to infiltrate the fluid for Doppler flowmeters to
operate perfectly. While the fluid is moderately opaque and does not enter the
fluid, the flowmeters tend to quantity the velocity of the fluid at or near the
pipe wall, which can cause substantial measurement error and cause the
flowmeter to fail.
No comments:
Post a Comment