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.)
“The principle of all sovereignty resides essentially in the nation.”
—French National Assembly. Declaration of the Rights of Man (Sept. 1791)
“In case I conk out, this is provisionally what I have to do: I must clarify obscurities; I must make clearer definite ideas or dissociations. I must find a verbal formula to combat the rise of brutality—the principle of order versus the split atom.”
—Ezra Pound (1885–1972)