If a volume of highly pressurized distilled water was rapidly de-pressurized, but kept the same volume, would the internal pressure within the volume dissipate by thermalization? If so, how much would the water heat up for say 5km beneath sea level to above sea level pressure? I'm thinking internal pressure is a potential energy, this works for steam where pressure is released by change in volume ( made useful with steam engines ). But water doesn't change volume much under pressure, so I wasn't sure if it worked the same. I know fluids will release energy if depressurized suddenly if they have a outgassing outlet, ( e.g. champange uncorked ). But its interesting to know if without a gas \ volume outlet a volume of distilled water would react to rapid depressurization. The only way I can think it could do this is thermalize its internal pressure. my thermodynamics is a bit rusty. Wondered if anyone knew.