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Updated: Jul 13, 2026
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
Cascade model for particle concentration and enstrophy in fully developed turbulence with mass-loading feedback
1Bay Area Environmental Research Institute, MS 245-3, Moffett Field, California 94035-1000, USA. hogan@cosmic.arc.nasa.gov
Summary
A new cascade model for turbulent particle-laden flows uses multiplier distributions from 3D simulations. It accurately predicts particle concentration and enstrophy, showing mass loading reduces high concentrations.
Area of Science:
- Fluid Dynamics
- Multiphase Flow
- Computational Physics
Background:
- Turbulent particle-laden flows are complex, involving interactions between fluid and particles.
- Accurate modeling is crucial for understanding phenomena like pollutant dispersion and industrial processes.
Purpose of the Study:
- To develop and validate a cascade model for turbulent particle-laden flows.
- To investigate the influence of particle mass loading on flow properties.
Main Methods:
- Three-dimensional direct numerical simulations (DNS) of two-way coupled flows.
- Solving Eulerian equations using pseudospectral methods.
- Determining multiplier distributions from DNS data for cascade model parameterization.
Main Results:
- Multiplier probability distribution functions (PDFs) are well-described by the beta distribution.
- Intermittency (PDF width) decreases with increasing mass loading.
- The cascade model accurately reproduces joint PDFs of concentration and enstrophy.
Conclusions:
- Particle mass loading significantly reduces probabilities of high particle concentration and enstrophy.
- The cascade model offers computational savings for simulating turbulent particle-laden flows.
- The approach shows promise for predicting flow behavior beyond direct simulation capabilities.
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