About the 3D simulation of the boiling of liquid films and spray droplets during their contact with hot substrates

Abstract

Boiling of liquids upon impact of the spray on heated surfaces is common in many practical applications. However, a comprehensive modelling approach for these phenomena is still not available in commercial software, despite decades of experimental, theoretical, and numerical research efforts. The motivation of this paper is to clarify the state of the art on the three-dimensional (3D) simulation of the boiling of liquid films and spray droplets during their contact with hot substrates. Based on recent experimental and theoretical research, this paper proposes a set of heat transfer models for 3D simulation of spray cooling considering conjugate heat transfer (CHT). These updated models and correlations were implemented in a computational fluid dynamics (CFD) solver, which already included a classical two-phase Lagrangian–Eulerian approach and CHT modelling functionality. A detailed validation of the improved modelling proposals is performed using a unique and novel database including wall surface temperature and heat flux measurements for different flow rates and spray impact velocities. Excellent agreement with experiments was obtained for all boiling regimes using a Leidenfrost-like temperature to manage the prompt heat flux change between the film boiling regime and the transition boiling regime. Most notable are the great results produced by the recent film boiling model summarized in this article.Graphical Abstract