Properties of sound in water

Hello,
I'm in my first year of engineering, and I have a project that involves the
scrambling of data using sound.
The set up is as follows:
-input a 4 digit number into a computer
-the computer scrambles the number using matrix algebra
-each number from the matrix has an associated sound to it (for a maximum of
18 sounds)
-the sound will be send through water via a submerged speaker
-the sound will be received via a submerged microphone
now here is where I'm stuck. I need to know what effects water has on
sound. I know for sure that the velocity changes. But in order to continue
my project, I have to be able to calculate what the original source sound
is.
Would the sound change frequency?
Anyways, once received and re-calculated, the sound would be reassigned to
its number between 1-18 and be put back through the inverse matrix to
retrieve the original 4 digit code.
Thank you for any help
-Tom Kurowski
tom_kurowski@ hot mail [dot] com
Reply to
Tom Kurowski
Loading thread data ...
In general, the frequency is static, and the wavelength varies with transmission speed. If there is a relative speed between the transmitter and receiver however, there is a doppler shift in the nominal frequency.
Brian W
Reply to
Brian Whatcott
Dear Tom Kurowski:
The frequency will become a function of fluid velocity difference between source and receiver. If it is largely "static" water, there should be no surprises. Now calibration of an acoustic source (detector) in the air, that is to be operated in the water, will be a problem.
David A. Smith
Reply to
N:dlzc D:aol T:com (dlzc)
speeds of sound in any fluid (called "a") is :
a = sqrt (gamma * R * T)
where gamma = Cp/Cv of water (depends on temperature of the fluid, you can find that in any fluid books) R = Ru/MW_water T = absolute temperature, generally in kelvin (depends on the units of R)
Ru is the universal gas constant MW_water is the water atomic weight, can be found in any chemical reference
--------- Mathieu Fregeau
Reply to
Mathieu Fregeau

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.