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arXiv · 1902.05435

Clustering and energy spectra in two-dimensional dusty gas turbulence

Vikash Pandey·Dhrubaditya Mitra·Prasad Perlekar
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Abstract

We present Direct Numerical Simulation (DNS) of heavy inertial particles (dust) immersed in two-dimensional turbulent flow (gas). The dust are modeled as mono-dispersed heavy particles capable of modifying the flow through two-way coupling. By varying the Stokes number (St) and the mass-loading parameter $({\phi}_{\rm m})$, we study the clustering phenomenon and the gas phase kinetic energy spectra. We find that the dust-dust correlation dimension $(d_2)$ also depends on ${\phi}_{\rm m}$. In particular, clustering decreases as mass-loading $({\phi}_{\rm m})$, is increased. In the kinetic energy spectra of gas we show: (i) emergence of a new scaling regime, (ii) the scaling exponent in this regime is not unique but rather a function of both St and $({\phi}_{\rm m} )$. Using a scale-by-scale enstrophy budget analysis we show in the new scaling regime, viscous dissipation due to the gas balances back-reaction from the dust.

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Vikash Pandey, Dhrubaditya Mitra, Prasad Perlekar. 2019-02-14. Clustering and energy spectra in two-dimensional dusty gas turbulence. https://doi.org/10.1103/physreve.100.013114

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