Accession Number : AD0428991

Title :   THE TRANSMISSION OF SOUND IN A MOVING FLUID.

Corporate Author : HARTFORD UNIV CONN

Report Date : 06 FEB 1964

Pagination or Media Count : 10

Abstract : Techniques were developed for measuring sound in moving fluids. A basic closed loop recirculating system was designed which includes a centrifugal booster pump, a by-pass, and four similar parallel lines, each with a different test section. An acoustical signal is introduced into the stream of moving fluid by means of a transducer at one end of each of the four parallel lines. The velocity of the fluid and the frequency of the input signal are both controlled variables. After the signal has traveled through the full length of the test section, it is detected and its intensity measured by a device which also shows its wave pattern on an oscilloscope. Pertinent data gathered in this manner are recorded and later analyzed for specific purpose. A secondary object is to determine the validity of a theory that certain test elements will act as mufflers of sound in a moving fluid. The fluid in this first instance is water at room temperature. It is desired to know the extent of sound attenuation which might be realized by inserting a mechanical device into the moving stream without creating additional turbulence in the flow pattern. (Author)

Descriptors :   (*SOUND TRANSMISSION, FLUID FLOW), MOTION, ACOUSTIC SIGNALS, ATTENUATION, TEST METHODS, WATER, INSTRUMENTATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE