Principle
Ultrasonic flow meters measure the difference of the transit time of ultrasonic pulses propagating in and against flow direction. 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 and and the distance between receiving and transmitting transducers and the inclination angle one can write the equations:
and
where is the average velocity of the fluid along the sound path and is the speed of sound.
Read more about this topic: Ultrasonic Flow Meter
Famous quotes containing the word principle:
“There is no teaching until the pupil is brought into the same state or principle in which you are; a transfusion takes place; he is you, and you are he; then is a teaching; and by no unfriendly chance or bad company can he ever lose the benefit.”
—Ralph Waldo Emerson (1803–1882)
“The principle of fashion is ... the principle of the kaleidoscope. A new year can only bring us a new combination of the same elements; and about once in so often we go back and begin again.”
—Katharine Fullerton Gerould (1879–1944)
“Experimental work provides the strongest evidence for scientific realism. This is not because we test hypotheses about entities. It is because entities that in principle cannot be ‘observed’ are manipulated to produce a new phenomena
[sic] and to investigate other aspects of nature.”
—Ian Hacking (b. 1936)