ABSTRACT
There are many industrial situations in which the vapour pressure of the liquid circulated is not negligible; typically it is some tenths to many tens of bars. Under these conditions it is observed that cavitation is produced in a rather surprising manner, very different from the one which is commonly seen in the so-called ‘cold’ liquids like water or mercury at ordinary temperatures or even liquid sodium. Bubble cavitation in cold liquids is correctly described by the Rayleigh-Plesset equation in which the vapour pressure is considered constant, equal to that corresponding to the temperature of the surrounding liquid. The vapour produced is in contact with the cooled liquid whose vapour pressure is lower than that of the liquid away from the bubble. Consequently, development of the bubble takes place at a pressure which is lower than what it would be in the case of a cold liquid; this phenomenon is called ‘thermodynamic attenuation of cavitation.’.
