English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We report on the modification of the spectrum of a passive scalar inside aturbulent flow by the injection of large bubbles. While the spectralmodification through bubbles is well known and well analyzed for the velocityfluctuations, little is known on how bubbles change the fluctuations of anapproximately passive scalar, in our case temperature. Here we uncover thethermal spectral scaling behavior of a turbulent multiphase thermal mixinglayer. The development of a $-3$ spectral scaling is triggered. By injectinglarge bubbles ($\text{Re}_{\text{bub}} = \mathcal{O}(10^2)$) with gas volumefractions $\alpha$ up to 5\%. For these bubbly flows, the $-5/3$ scaling isstill observed at intermediate frequencies for low $\alpha$ but becomes lesspronounced when $\alpha$ further increases and it is followed by a steeper $-3$slope for larger frequencies. This $-3$ scaling range extends with increasinggas volume fraction. The $-3$ scaling exponent coincides with the typicalenergy spectral scaling for the velocity fluctuations in high Reynolds numberbubbly flows. We identify the frequency scale of the transition from the $-5/3$scaling to the $-3$ scaling and show how it depends on the gas volume fraction.

The emergence of bubble-induced scaling in thermal spectra in turbulence