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Originally Posted by FERdeBOER
Another thing: the phisycs on the air could not be applied to water. Both are fluids, of course, but liquids (water in this case) are much more dense and complex than the air.
In fact, there no exits a unique formula for the speed of sound in the water. There are one for each place, even for each season, and all this formulas are made by empiric experients, no theorical.
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Thats true : if both are fluid, the water have much more viscosity than the air, I can't remember the value exactly but this should be around 100 times.
As you said, most of sound propagation in water are empiric, but there at least a quite known formula to help to compute when turbulence start : it's the Law of Poiseuille, which, coupled with Reynolds number can tell you at what time a hull will start to create turbulence.
The Reynolds number is used to transpose the turbulence effect to a same hull at different scales.
Sound propagation in the water and the time laminar flow become turbulent are 2 different things.
First is mainly from experience (even some formula exist) the other is very well known and ""easily"" calculable (if you have the right data ... including hull size and form and viscosity of the environment)