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تسجيل مستخدم جديدHydrodynamic correlations and instabilities in stress-balanced pusher-puller mixtures
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Multispecies swarms are found for microorganisms living in microfluidic environments where they can take advantage of collective motions during transport and spreading. Nevertheless, there is a general lack of physical understandings of the origins of the multiscale unstable dynamics. Here we build a computation model to study the binary suspensions of rear- and front-actuated microswimmers, or respectively the so-called pusher and puller particles, that have different populations and swimming speeds. We perform direct particle simulations to reveal that even in the scenarios of stress-balanced mixtures which produce approximately zero net extra stresses, the longtime dynamics can exhibit non-trivial density fluctuations and spatially-correlated motions. We then construct a continuum kinetic model and perform linear stability analysis to reveal the underlying mechanisms of hydrodynamic instabilities. Our theoretical predictions qualitatively agree with numerical results and explain the onsets of the observed collective motions.
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Suspensions of rear- and front-actuated microswimmers immersed in a fluid, known respectively as ``pushers and ``pullers, display qualitatively different collective behaviours: beyond a characteristic density, pusher suspensions exhibit a hydrodynami
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Eutectic gallium-indium (EGaIn), a room-temperature liquid metal alloy, has the largest tension of any liquid at room temperature, and yet can nonetheless undergo fingering instabilities. This effect arises because, under an applied voltage, oxides d
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Understanding the mechanics of detrimental convective instabilities in drying polymer solutions is crucial in many applications such as the production of film coatings. It is well known that solvent evaporation in polymer solutions can lead to Raylei
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