🎉 Congratulations to Edoardo Cipriano on his latest research publication! We are happy to share this work, published in the International Journal of Heat and Mass Transfer, with title: Coupling volume-of-fluid and chemical kinetics for direct numerical simulations of droplet combustion
The paper presents a fully multidimensional multiphase CFD framework capable of resolving: i) Multicomponent phase change at the liquid–gas interface; ii) Realistic chemical reactions using detailed combustion kinetics; iii) droplet suspension via surface tension; iv) variable thermodynamic and transport properties.
The proposed model enables high-fidelity simulations of single droplets in both microgravity and normal gravityconditions, with accurate predictions of burning rates, extinction, and the effects of COâ‚‚ enrichment and droplet size. The work clearly demonstrates the limitations of classical 1D models in capturing multidimensional and gravity-driven effects.
We are particularly proud that OpenSMOKE++ was used as the core chemical kinetics engine to solve the stiff combustion chemistry within this advanced CFD framework, allowing the direct integration of detailed kinetic mechanisms.
This powerful combination of VOF-based multiphase CFD and high-fidelity chemical kinetics opens the door to future investigations of droplet interactions, breakup-coalescence, and the development of reliable sub-grid models for engineering applications.
Explore the full paper and model here: https://www.sciencedirect.com/science/article/pii/S0017931025009238#d1e276
Cipriano E., Caraccio R. Frassoldati A., Faravelli T., Cuoci A., Coupling volume-of-fluid and chemical kinetics for direct numerical simulations of droplet combustion (2025) International Journal of Heat and Mass Transfer, art. no. 127586, DOI: https://doi.org/10.1016/j.ijheatmasstransfer.2025.127586
Abstract
Since the development of the d-squared law, in 1952, numerical modeling of droplet combustion has predominantly relied on the assumption of spherical symmetry. In this work, we relax this hypothesis by introducing a strategy to combine interface-resolved phase change models with the direct solution of the combustion chemistry. The multiphase system is described using the geometric Volume-Of-Fluid approach, previously extended to simulate the evaporation of mixtures with variable thermodynamic and transport properties. Gas-phase chemical reactions are incorporated using an operator splitting technique, addressing the stiffness and non-linearity of the reactive step. The model is validated by comparing its predictions with experimental data and with a spherically-symmetric model, proving convergence and capturing the burning rates accurately. The impact of natural convective fluxes at different ambient pressures is quantified by suspending the droplet on a solid fiber in normal gravity conditions. Lastly, the multicomponent formulation is employed to predict droplet extinction resulting from water absorption. The model’s implementation and simulation setups are publicly available on the Basilisk code website..