Spray formation: a numerical closeup

TL;DR

This paper presents high-resolution direct numerical simulations of spray formation in a gas-liquid mixing layer, aiming to visualize detailed atomization mechanisms and assess the adequacy of current computational resources for fully resolving all physical scales involved.

Contribution

It performs large-scale 3D direct numerical simulations of spray formation using up to 4 billion cells, providing insights into atomization processes and evaluating the sufficiency of current computational capabilities.

Findings

High-fidelity visualization of spray formation mechanisms

Assessment of computational resources for fully resolved simulations

Identification of unresolved physical scales in current models

Abstract

Spray formation and atomization in a gas-liquid mixing layer is an important fundamental problem of multiphase flows. It is highly desirable to visualize the detailed atomization process and to analyze the instabilities and mechanisms involved, and massive numerical simulations are required, in addition to experiment. Rapid development of numerical methods and computer technology in the past decades now allows large-scale three-dimensional direct numerical simulations of atomization to be performed. Nevertheless, the fundamental question, whether all the physical scales involved in the primary breakup process are faithfully resolved, remains unclear. In the present study, we conduct direct numerical simulations of spray formation in a gas-liquid mixing layer with state-of-the-art computational resources (using up to 4 billion cells and 16384 cores), in order to obtain a high-fidelity numerical closeup of the detailed mechanisms of spray formation. We also aim to examine whether present computational resources are sufficient for a fully resolved direct numerical simulation of atomization.