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1. Non-Newtonian fluid–structure interactions: Static response of a microchannel due to internal flow of a power-law fluid

   https://doi.org/10.1016/j.jnnfm.2018.12.008  

   Anand, Vishal ; JR, Joshua David ; Christov, Ivan C. ( December 2018 , Journal of Non-Newtonian Fluid Mechanics)
2. An efficient FLIP and shape matching coupled method for fluid–solid and two-phase fluid simulations

   https://doi.org/10.1007/s00371-018-1569-8  

   Gao, Yang ; Li, Shuai ; Qin, Hong ; Xu, Yinghao ; Hao, Aimin ( December 2019 , The Visual Computer)

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3. PASSIVE DIRECTIONAL MOTION OF FLUID DURING BOILING DRIVEN BY SURFACE ASYMMETRY IN A DIELECTRIC FLUID

   https://doi.org/10.1615/JEnhHeatTransf.2019027652  

   Bhavnani, Sushil ; Narayanan, Vinod ; Thiagarajan, Naveenan ; Strid, Logan ( January 2019 , Journal of Enhanced Heat Transfer)
4. An introductory guide to fluid models with anisotropic temperatures. Part 2. Kinetic theory, Padé approximants and Landau fluid closures

   https://doi.org/10.1017/S0022377819000850  

   Hunana, P. ; Tenerani, A. ; Zank, G. P. ; Goldstein, M. L. ; Webb, G. M. ; Khomenko, E. ; Collados, M. ; Cally, P. S. ; Adhikari, L. ; Velli, M. ( December 2019 , Journal of Plasma Physics)

   In Part 2 of our guide to collisionless fluid models, we concentrate on Landau fluid closures. These closures were pioneered by Hammett and Perkins and allow for the rigorous incorporation of collisionless Landau damping into a fluid framework. It is Landau damping that sharply separates traditional fluid models and collisionless kinetic theory, and is the main reason why the usual fluid models do not converge to the kinetic description, even in the long-wavelength low-frequency limit. We start with a brief introduction to kinetic theory, where we discuss in detail the plasma dispersion function $Z(\unicode[STIX]{x1D701})$ , and the associated plasma response function $R(\unicode[STIX]{x1D701})=1+\unicode[STIX]{x1D701}Z(\unicode[STIX]{x1D701})=-Z^{\prime }(\unicode[STIX]{x1D701})/2$ . We then consider a one-dimensional (1-D) (electrostatic) geometry and make a significant effort to map all possible Landau fluid closures that can be constructed at the fourth-order moment level. These closures for parallel moments have general validity from the largest astrophysical scales down to the Debye length, and we verify their validity by considering examples of the (proton and electron) Landau damping of the ion-acoustic mode, and the electron Landau damping of the Langmuir mode. We proceed by considering 1-D closures at higher-order moments than the fourth order, and as was concluded in Part 1, this is not possible without Landau fluid closures. We show that it is possible to reproduce linear Landau damping in the fluid framework to any desired precision, thus showing the convergence of the fluid and collisionless kinetic descriptions. We then consider a 3-D (electromagnetic) geometry in the gyrotropic (long-wavelength low-frequency) limit and map all closures that are available at the fourth-order moment level. In appendix A, we provide comprehensive tables with Padé approximants of $R(\unicode[STIX]{x1D701})$ up to the eighth-pole order, with many given in an analytic form. 

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5. Entropic colloidal crystallization pathways via fluid–fluid transitions and multidimensional prenucleation motifs

   https://doi.org/10.1073/pnas.1905929116  

   Lee, Sangmin ; Teich, Erin G. ; Engel, Michael ; Glotzer, Sharon C. ( July 2019 , Proceedings of the National Academy of Sciences)

   Complex crystallization pathways are common in protein crystallization, tetrahedrally coordinated systems, and biomineralization, where single or multiple precursors temporarily appear before the formation of the crystal. The emergence of precursors is often explained by a unique property of the system, such as short-range attraction, directional bonding, or ion association. But, structural characteristics of the prenucleation phases found in multistep crystallization remain unclear, and models are needed for testing and expanding the understanding of fluid-to-solid ordering pathways. Here, we report 3 instances of 2-step crystallization of hard-particle fluids. Crystallization in these systems proceeds via a high-density precursor fluid phase with prenucleation motifs in the form of clusters, fibers and layers, and networks, respectively. The density and diffusivity change across the fluid–fluid phase transition increases with motif dimension. We observe crystal nucleation to be catalyzed by the interface between the 2 fluid phases. The crystals that form are complex, including, notably, a crystal with 432 particles in the cubic unit cell. Our results establish the existence of complex crystallization pathways in entropic systems and reveal prenucleation motifs of various dimensions. 

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