Temperature depression model for cavitating flow with thermodynamic suppression effect in high-temperature water

TL;DR

This paper develops a temperature depression model for cavitating flow in high-temperature water, incorporating thermodynamic suppression effects to accurately predict temperature differences inside cavitation bubbles.

Contribution

The study introduces a novel temperature depression model that includes evaporative mass flux suppression, improving accuracy over existing models at high temperatures.

Findings

Model accurately reproduces experimental temperature data up to 140°C.

Inclusion of evaporative mass flux suppression is crucial for high-temperature cavitation.

Model parameters relate to characteristic temperature, Nusselt number, and thermodynamic suppression factors.

Abstract

The thermodynamic suppression effect of cavitation generally appears in cryogenic cavitating flows. Temperature depression, which is the temperature difference between the mainstream and inside the cavity, indicates the thermodynamic suppression effect. In this study, a temperature depression model is developed to understand the physical process of the thermodynamic suppression effect. The model is evaluated using the experimental data of temperature inside supercavitation in high-temperature water of up to 140 $^\circ$C. The temperature depression model is derived based on Fruman's model and newly introducing the suppression effect of evaporative mass flux. At first, Fruman's model was compared with the experimental data. Fruman's model differed from the experimental data in the high-temperature region of more than 100 $^\circ$C. In contrast, the proposed model reproduced the experimental data well in the high-temperature region. Therefore, introducing a suppression effect of evaporative mass flux is essential for describing the temperature depression in cavitating flow. In addition, the proposed model was expressed with existing parameters, and it was clear that the temperature depression was defined with the characteristic temperature of the B factor, the Nusselt number, and a term representing the suppression effect of evaporative mass flux expressed by dimensionless thermodynamic parameters.