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arXiv · 2212.04989

Energy spectra of buoyancy-driven bubbly flow in a vertical Hele-Shaw cell

Rashmi Ramadugu·Vikash Pandey·Prasad Perlekar
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Abstract

We present direct numerical simulations (DNS) study of confined buoyancy-driven bubbly flows in a Hele-Shaw setup. We investigate the spectral properties of the flow and make comparisons with experiments. The energy spectrum obtained from the gap-averaged velocity field shows $E(k) \sim k$ for $k < k_d$, $E(k) \sim k^{-5}$ for $k > k_d$, and an intermediate scaling range with $E(k) \sim k^{-3}$ around $k \sim k_d$. We perform an energy budget analysis to understand the dominant balances and explain the observed scaling behavior. We also show that the Navier-Stokes equation with a linear drag can be used to approximate large scale flow properties of bubbly Hele-Shaw flow.

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Rashmi Ramadugu, Vikash Pandey, Prasad Perlekar. 2022-12-09. Energy spectra of buoyancy-driven bubbly flow in a vertical Hele-Shaw cell. https://arxiv.org/abs/2212.04989

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