AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Modeling and Simulation of Droplet Breakup: A Lagrangian Volume-of-Fluid Approach to Turbulent Spray Formation
EVERETT WENZEL, WanJiao Liu, Sean Garrick, University of Minnesota
Abstract Number: 605 Working Group: Instrumentation and Methods
Abstract Liquid aerosol formation, or atomization, is important to a variety of industrial applications, including inhalation aerosols, agricultural sprays, and power generation. Tools capable of predicting atomization – droplet size distributions, break-up lengths, penetration depths, etc. – are useful for the design of these processes. In turbulent flows, liquid break-up involves primary and secondary atomization. Primary atomization encompasses the initial instability-induced breakup of the liquid into large ligaments and droplets, and secondary atomization encompasses the subsequent breakup of the ligaments and droplets by fluid shear stress. Current modeling and simulation methods require prodigious amounts of compute time, fail to satisfy conservation laws, or introduce numerical artifacts which decrease accuracy. We present a new approach – termed the Lagrangian volume of fluid – for the simulation of turbulent, multiphase flows. The method achieves conservation and provides accurate interface curvature and sub-grid-scale phase information by coupling a Lagrangian phase-identifying particle domain with an Eulerian computational mesh. The method propagates phase interfaces without oscillation or artificial diffusion on structured and unstructured grids because they are treated in a Lagrangian sense. Kernel approximations from smoothed particle hydrodynamics are used to produce the surface tension force from the Lagrangian particles, which is inserted into the Eulerian Navier-Stokes solver. The result is an approach capable of accurately and robustly capturing primary and secondary atomization, which lends itself to engineering applications.