A Mass Tracking Formulation for Bubbles in Incompressible Flow

Abstract

We devise a novel method for treating bubbles in incompressible flow that relies on the conservative advection of bubble mass and an associated equation of state in order to determine pressure boundary conditions inside each bubble. We show that executing this algorithm in a traditional manner leads to stability issues similar to those seen for partitioned methods for solid-fluid coupling. Therefore, we reformulate the problem monolithically. This is accomplished by first proposing a new fully monolithic approach to coupling incompressible flow to fully nonlinear compressible flow including the effects of shocks and rarefactions, and then subsequently making a number of simplifying assumptions on the air flow removing not only the nonlinearities but also the spatial variations of both the density and the pressure. The resulting algorithm is quite robust, has been shown to converge to known solutions for test problems, and has been shown to be quite effective on more realistic problems including those with multiple bubbles, merging and pinching, etc. Notably, this approach departs from a standard two-phase incompressible flow model where the air flow preserves its volume despite potentially large forces and pressure differentials in the surrounding incompressible fluid that should change its volume. Our bubbles readily change volume according to an isothermal equation of state.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 14, 2012
Accession Number
ADA579230

Entities

People

  • Mridul Aanjaneya
  • Ronald Fedkiw
  • Saket Patkar

Organizations

  • Stanford University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Advection
  • Air Flow
  • Algorithms
  • Boundaries
  • Compressible Flow
  • Computational Science
  • Couplings
  • Equations
  • Gas Laws
  • Incompressible Flow
  • Poisson Equation
  • Pressure Gradients
  • Rarefaction
  • Shock Waves
  • Standards
  • Surface Tension
  • Two Dimensional

Readers

  • Computational Fluid Dynamics (CFD)
  • Distributed Systems and Data Platform Development
  • Fluid Dynamics.