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:
“The principle of subordination is the great bond of union and harmony through the universe.”
—Catherine E. Beecher (1800–1878)
“Look through the whole history of countries professing the Romish religion, and you will uniformly find the leaven of this besetting and accursed principle of action—that the end will sanction any means.”
—Samuel Taylor Coleridge (1772–1834)
“I ... observed the great beauty of American government to be, that the simple machines of representation, carried through all its parts, gives facility for a being moulded at will to fit with the knowledge of the age; that thus, although it should be imperfect in any or all of its parts, it bears within it a perfect principle the principle of improvement.
”
—Frances Wright (1795–1852)