Just something that came up to me while I was having a conversation about submarines: Since deuterium oxide (heavy water) is far denser than water and has different characteristics than normal salt water, what would happen when a propeller reaches an rpm that would create cavitation in normal water? If there are any specific characteristics of deuterium that are important that I'm missing here please include them.
Deuterium is an isotope of hydrogen with an additional neutron in the nucleus.I suspect that you are talking about heavy water, where the two hydrogen atoms are replaced by deuterium, and not of liquid deuterium, as @probably-someone has rightly pointed out. The density of heavy water is $1.107 g/cm^3$. Thus it is not so much higher than normal water. The difference in density and a small increase boiling temperature to $101.4°C$ (decrease in vapor pressure) would probably be the most important differences to water which could have an influence on cavitation.