# Understanding the thermodynamics of cavitation

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Cavitation is a phenomena that occurs in liquids when the local static pressure drops below the vapor pressure; bubbles form within the liquid.

I am studying cavitation in incompressible, two-phase (liquid & gas), homogeneous mixture of cryogenic fluids (liquid nitrogen in particular) within pipes and would like to understand the thermal effects involved. My main sources are: 1) "Implementation and validation of an extended Schnerr-Sauer cavitation model for non-isothermal flows in OpenFOAM" (https://www.sciencedirect.com/science/article/pii/S1876610217335397 section 2.3: Thermal model) and 2) "Method for prediction of pump cavitation performance for various liquids, liquid temperatures, and rotative speeds" (https://ntrs.nasa.gov/api/citations/19690019787/downloads/19690019787.pdf section: Determination of Cavity Pressure Depressions).

I would like to understand and discuss the thermal models they propose and see if they are applicable to my particular case.

When referring to heat transfer I mean convective heat transfer (which I assume to be a combination of conduction and advection).

1. They state "The convective heat transfer term is subtracted from the latent heat source term". Why? What I understand from this is that latent heat and heat transfer compete but I do not quite get why this should be the case. Let's look at the case of vaporization; the vaporization heat needed for vaporization of a liquid is the convective heat transfer needed to reach vaporization temperature and the latent heat of vaporization of the liquid, and not the difference...

2. They set a heat balance between the heat required for vaporization and the heat drawn from the liquid surrounding the cavity (that is, the liquid-vapor interface).

So I think that they are essentially stating the same idea: the net heat transfer for vaporization is the difference between net latent heat transfer and convective heat transfer.

This question has also been asked on PSE (https://physics.stackexchange.com/questions/703431/understanding-thermal-models-of-cavitation) and on PF (https://www.physicsforums.com/threads/understanding-cavitation.1014195/)