Performance evaluation of the cavities on nucleate boiling at microscale level

TL;DR

This study uses numerical simulations to analyze how cavity structures on roughened surfaces affect nucleate boiling heat transfer, focusing on bubble dynamics and heat flux at the microscale.

Contribution

It introduces a phase-change lattice Boltzmann model to investigate cavity effects on nucleation and boiling performance without artificial disturbances.

Findings

Cavity width and groove shape significantly influence boiling heat transfer.

Circular groove cavities outperform others in heat flux and bubble release.

Nucleation behavior varies with cavity configuration on roughened surfaces.

Abstract

Nucleate boiling heat transfer (NBHT) from enhanced structures is an effective way to dissipate high heat flux. In the present study, the cavities behaviours for nucleation on roughened surface are numerically studied on the entire ebullition cycle based on a phase-change lattice Boltzmann method without introducing any artificial disturbances. The adopted model is firstly validated with the Laplace law and the two phase coexistence curve, and then applied to investigate the effects of cavity structure on NBHT. The bubble departure diameter, departure frequency and total boiling heat flux of an ebullition cycle are also explored. It is demonstrated that the cavity widths and the cavity grooves show significant influence on the features of NBHT. Cavity with circular groove in the present research shows the best performance for NBHT in terms of the averaged heat flux and bubble release frequency. When a specific cavity is combined with other different cavities on roughened surfaces its nucleation process on different roughened surfaces may differ greatly.