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 a good principle which created order, light, and man, and an evil principle which created chaos, darkness, and woman.”
—Pythagoras (c. 572–497 B.C.)
“Well, you Yankees and your holy principle about savin’ the Union. You’re plunderin’ pirates that’s what. Well, you think there’s no Confederate army where you’re goin’. You think our boys are asleep down here. Well, they’ll catch up to you and they’ll cut you to pieces you, you nameless, fatherless scum. I wish I could be there to see it.”
—John Lee Mahin (1902–1984)
“A state of war or anarchy, in which law has little force, is so far valuable, that it puts every man on trial. The man of principle is known as such, and even in the fury of faction is respected.”
—Ralph Waldo Emerson (1803–1882)