Lattice Boltzmann modeling and simulation of forced-convection boiling on a cylinder

TL;DR

This paper introduces a robust lattice Boltzmann method for simulating forced-convection boiling on a cylinder, accurately capturing various boiling regimes and bubble dynamics across a wide range of flow conditions.

Contribution

It develops a CMs-based lattice Boltzmann scheme with enhanced stability and thermodynamic consistency for simulating complex boiling phenomena without artificial initial conditions.

Findings

Successfully reproduces nucleate, transition, and film boiling regimes.

Captures vapor bubble nucleation, growth, and departure across Reynolds numbers 30-30000.

Supports experimental observations of intermittent solid-liquid contact in film boiling.

Abstract

When boiling occurs in a liquid flow field, the phenomenon is known as forced-convection boiling. We numerically investigate such a boiling system on a cylinder in a flow at a saturated condition. To deal with the complicated liquid-vapor phase-change phenomenon, we develop a numerical scheme based on the pseudopotential lattice Boltzmann method (LBM). The collision stage is performed in the space of central moments (CMs) to enhance numerical stability for high Reynolds numbers. The adopted forcing scheme, consistent with the CMs-based LBM, leads to a concise yet robust algorithm. Furthermore, additional terms required to ensure thermodynamic consistency are derived in a CMs framework. The effectiveness of the present scheme is successfully tested against a series of boiling processes, including nucleation, growth, and departure of a vapor bubble for Reynolds numbers varying between 30 and 30000. Our CMs-based LBM can reproduce all the boiling regimes, i.e., nucleate boiling, transition boiling, and film boiling, without any artificial input such as initial vapor phase. We find that the typical boiling curve, also known as the Nukiyama curve, appears even though the focused system is not the pool boiling but the forced-convection system. Also, our simulations support experimental observations of intermittent direct solid-liquid contact even in the film-boiling regime. Finally, we provide quantitative comparison with the semi-empirical correlations for the forced-convection film boiling on a cylinder on the Nu-Ja diagram.