Computation of Spray Dynamics by Direct Solution of Moment Transport Equations

Abstract

In many spray applications, it is important to know the size and velocity distribution of the drops. Conventional particle tracking techniques can require prohibitively large computational times, especially in regions of low droplet number density or when detailed statistics are desired. In this paper, we develop a method to compute the statistics directly by solving a series of moment transport equations. A maximum entropy model is used to close higher-order moments appearing in the equations. Solution of these equations gives not only the transported moments of the spray, but also the maximum entropy probability distribution function from which further statistics can be obtained. The method has been tested on a quasi-one-dimensional spray problem to assess its viability. Submodels which account for the effects of the gas on the drops, including turbulence modification and correlation between the gas and drop velocities, are incorporated. Results for expected quantities are in good agreement with the solution from a particle tracking simulation.

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Document Details

Document Type
Technical Report
Publication Date
Sep 27, 1999
Accession Number
ADA410053

Entities

People

  • Christopher F. Edwards
  • Mark R. Archambault

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force Research Laboratories
  • Boltzmann Equation
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Distribution Functions
  • Dynamics
  • Equations
  • Flow
  • Leading Edges
  • Mechanical Engineering
  • Probability
  • Probability Density Functions
  • Probability Distributions
  • Random Variables
  • Statistics
  • Two Dimensional

Fields of Study

  • Mathematics

Readers

  • Computational Modeling and Simulation
  • Fluid Dynamics.
  • Internal Combustion Engine (ICE) Technology.