Simulation of liquid jet atomization and droplet breakup via a Volume-of-Fluid Lagrangian–Eulerian strategy

Abstract

The hybrid Volume-of-Fluid and Lagrangian–Eulerian (VoFLE) strategy is an attractive approach for reducing the computational cost of spray simulations while retaining a reasonable amount of fidelity. It is based on the concept of transitioning small liquid bodies or droplets to a Lagrangian–Eulerian (LE) representation, alleviating the burden of maintaining high resolution for small droplets. This hybrid VoFLE methodology is extended in the present work by incorporating a hydrodynamic breakup model based on maximum entropy formalism (MEF). This approach is particularly suitable for realistic spray conditions, such as high-pressure fuel injectors, where adequate numerical resolution of the smallest droplets is extremely difficult. The first step in the present VoFLE treatment is the identification of unresolved liquid structures targeted for LE transition. This step is followed by the application of the MEF breakup model for those structures that are hydrodynamically unstable, resulting in the assignment of secondary drop sizes and velocities. The model is evaluated statistically and tested against experimental data from the Engine Combustion Network and the breakup of a water jet. Relatively favorable results are encountered in these tests.

Primary spray breakup from a nasal spray atomizer using volume of fluid to discrete phase model

“…To date, no numerical studies can be found for the nasal spray application that resolves all the complex physics involved in primary atomization. Although, there are studies that have investigated breakup mechanisms from swirl atomizers (Patil and Sahu, 2021;Sahu et al, 2022;Kuo and Trujillo, 2022) and other atomizers such as hollow cones (Di Martino et al, 2022), air-blast (Patil and Sahu, 2021), and coaxial (Kumar and Sahu, 2020;Charalampous et al, 2019). Further computational studies of nasal spray applications can be used to provide a deeper understanding of the primary breakup of the liquid sheet which influences and secondary break-up of a nasal spray and eventually the droplet characteristics.…”