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   https://doi.org/10.1002/lno.10941  

   MacIntyre, Sally ; Crowe, Adam. T. ; Cortés, Alicia ; Arneborg, Lars ( November 2018 , Limnology and Oceanography)
2. Spectral turbulence kinetic energy budget and scale-based velocity decomposition for turbulence in bubble plumes

   https://doi.org/10.1063/5.0151046  

   Wu, Huijie ; Wang, Binbin ( June 2023 , Physics of Fluids)

   We conducted a spectral analysis of the turbulence kinetic energy (TKE) budget in a bubble plume using particle image velocimetry with fluorescent particles. Our findings confirmed the hypothesis of an inverse energy cascade in the bubble plume, where TKE is transferred from small to large eddies. This is attributed to direct injection of TKE by bubble passages across a wide range of scales, in contrast to canonical shear production of TKE in large scales. Turbulence dissipation was identified as the primary sink of the bubble-produced TKE and occurred at all scales. The decomposition of velocities using the critical length scale of inter-scale energy transfer allowed us to distinguish between large- and small-scale motions in the bubble plume. The large-scale turbulent fluctuations exhibited a skewed distribution and were likely associated with the return flow after bubble passage and the velocities induced by the bubble wake. The small-scale turbulent fluctuations followed a Gaussian distribution relatively well. The large-scale motions contributed to over half of the Reynolds stresses, while there were significant small-scale contributions to the normal stresses near the plume center but not to the shear stress. The large-scale motions in the vorticity field induced a street of vertically elongated vortex pairs, while the small-scale vortices exhibited similar sizes in both horizontal and vertical directions.

    

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3. V-ONSET (Vertical Octagonal Noncorrosive Stirred Energetic Turbulence): A vertical water tunnel with a large energy dissipation rate to study bubble/droplet deformation and breakup in strong turbulence

   https://doi.org/10.1063/1.5093688  

   Masuk, Ashik Ullah ; Salibindla, Ashwanth ; Tan, Shiyong ; Ni, Rui ( August 2019 , Review of Scientific Instruments)
4. A Study of the Effects of the Pore Size on Turbulence Intensity and Turbulence Length Scale in Forced Convection Flow in Porous Media

   Huang, C.-W. ; Srikanth, V. ; Kuznetsov, A.V. ( January 2018 , Proceedings of the 16th International Heat Transfer Conference, IHTC-16)
5. On the Conservation of Turbulence Energy in Turbulence Transport Models

   https://doi.org/10.3847/1538-4357/ac596e  

   Wang, B.-B. ; Zank, G. P. ; Adhikari, L. ; Zhao, L.-L. ( April 2022 , The Astrophysical Journal)

   Abstract Zank et al. developed models describing the transport of low-frequency incompressible and nearly incompressible turbulence in inhomogeneous flows. The formalism was based on expressing the fluctuating variables in terms of the Elsässar variables and then taking “moments” subject to various closure hypotheses. The turbulence transport models are different according to whether the plasma beta regime is large, of order unity, or small. Here, we show explicitly that the three sets of turbulence transport models admit a conservation representation that resembles the well-known WKB transport equation for Alfvén wave energy density after introducing appropriate definitions of the “pressure” associated with the turbulent fluctuations. This includes introducing a distinct turbulent pressure tensor for 3D incompressible turbulence (the large plasma beta limit) and pressure tensors for quasi-2D and slab turbulence (the plasma beta order-unity or small regimes) that generalize the form of the WKB pressure tensor. Various limits of the different turbulent pressure tensors are discussed. However, the analogy between the conservation form of the turbulence transport models and the WKB model is not close for multiple reasons, including that the turbulence models express fully nonlinear physical processes unlike the strictly linear WKB description. The analysis presented here both serves as a check on the validity and correctness of the turbulence transport models and also provides greater transparency of the energy dissipation term and the “turbulent pressure” in our models, which is important for many practical applications. 

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