Swimmer-Types of Optimum Surface-Driven Active ParticlesAn optimal microswimmer with a given geometry has a surface velocity profile that minimizes energy dissipation for a given swimming speed. An axisymmetric swimmer can be puller-, pusher-, or…Rafe Md Abu Zayed, Arezoo M. Ardekani, Amir Nourhani·Oct 5, 2024SaveLearn
Thermovelocimetric Characterization of Liquid Metal Convection in a Rotating Slender CylinderRotating turbulent convection occurs ubiquitously in natural convective systems encompassing planetary cores, oceans, and atmospheres, as well as in many industrial applications. While the global…Yufan Xu, Jewel Abbate, Cy David et al.·Oct 4, 2024SaveLearn
Fluctuation-dissipation theorems and the measurement of the Onsager coefficients for two-phase flow in porous mediaWe propose a new methodology for the experimental measurement of the Onsager coefficients of porous media flows by application of the fluctuation-dissipation theorem. The experimental setup consists…Marcel Moura, Dick Bedeaux, Ryan T. Armstrong et al.·Oct 4, 2024SaveLearn
Dam break of viscoplastic elliptical objectsIn this note, we numerically and theoretically analyze the physical mechanisms controlling the gravity-induced spreading of viscoplastic elliptical metric objects on a sticky solid surface (without…Kindness Isukwem, Anselmo Pereira·Oct 4, 2024SaveLearn
Force balances in spherical shell rotating convectionSignificant progress has been made in understanding planetary core dynamics using numerical models of rotating convection (RC) in spherical shell geometry. However, the behaviour of forces in these…S. Naskar, C. J. Davies, J. E. Mound et al.·Oct 4, 2024SaveLearn
Reduced-Order Modelling and Closed-Loop Control of the Cylinder WakeWe present a model-based approach for the closed-loop control of vortex shedding in the cylinder wake. The control objective is to suppress the unsteadiness of the flow, which arises at a critical…Tea Vojković, Dimitris Boskos, Abel-John Buchner·Oct 4, 2024SaveLearn
Extending Kolmogorov Theory to Polymeric TurbulenceThe addition of polymers fundamentally alters the dynamics of turbulent flows in a way that defies Kolmogorov predictions. However, we now present a formalism that reconciles our understanding of…Alessandro Chiarini, Rahul K. Singh, Marco E. Rosti·Oct 4, 2024SaveLearn
On the emergence of criticality for inhalation-driven particle deposition in the anatomical upper airwayInhalation directs air through a defined pathway, initiating from nostrils, moving through the main nasal cavity, past the pharynx and trachea, and culminating in the lungs. Inhaled particles, of a…Emma Louwagie, Saikat Basu·Oct 3, 2024SaveLearn
Elastoinertial turbulence: Data-driven reduced-order model based on manifold dynamicsElastoinertial turbulence (EIT) is a chaotic state that emerges in the flows of dilute polymer solutions. Direct numerical simulation (DNS) of EIT is highly computationally expensive due to the need…Manish Kumar, C. Ricardo Constante-Amores, Michael D. Graham·Oct 3, 2024SaveLearn
Particle Re-Suspension in Two-Phase Dispersed Rayleigh-B\'enard ConvectionThe process by which particles are entrained by the fluid in Rayleigh-B\'enard convection is studied by means of particle-resolved numerical simulations in a periodic domain at a Rayleigh number of…Xianyang Chen, Rodolfo Ostilla Monico, Daniel Floryan et al.·Oct 3, 2024SaveLearn
Rescaled Equations for Well-Conditioned Direct Numerical Simulations of Rapidly Rotating ConvectionConvection is a ubiquitous process driving geophysical/astrophysical fluid flows, which are typically strongly constrained by planetary rotation on large scales. A celebrated model of such flows,…Keith Julien, Adrian van Kan, Benjamin Miquel et al.·Oct 3, 2024SaveLearn
Machine-learned flow estimation with sparse data -- exemplified for the rooftop of a UAV vertiportWe propose a physics-informed data-driven framework for urban wind estimation. This framework validates and incorporates the Reynolds number independence for flows under various working conditions,…Chang Hou, Luigi Marra, Guy Y. Cornejo Maceda et al.·Oct 3, 2024SaveLearn
Instability in centrifugally stable shear flowsWe investigate the linear instability of flows that are stable according to Rayleigh's criterion for rotating fluids. Using Taylor-Couette flow as a primary test case, we develop large Reynolds…Kengo Deguchi, Ming Dong·Oct 3, 2024SaveLearn
Impact of topography and combustion functions on fire front propagation in an advection-diffusion-reaction model for wildfiresGiven the recent increase in wildfires, developing a better understanding of their dynamics is crucial. For this purpose, the advection-diffusion-reaction model has been widely used to study wildfire…Luca Nieding, Cordula Reisch, Dirk Langemann et al.·Oct 2, 2024SaveLearn
Tailoring formations of self-organizing hydrofoil schools towards high-efficiencyWe present new unconstrained simulations and constrained experiments of a pair of pitching hydrofoils in a leader-follower in-line arrangement. Free-swimming simulations of foils with matched…Tianjun Han, Amin Mivehchi, Seyedali Seyedmirzaei Sarraf et al.·Oct 2, 2024SaveLearn
On the Accuracy of Compressibility TransformationsThis study highlights the importance of satisfying the eddy viscosity equivalence below the logarithmic layer, to deriving accurate compressibility transformations. First, we analyze the ability of…M. Engin Danis, Paul Durbin·Oct 2, 2024SaveLearn
Highly deformable flapping membrane wings suppress the leading edge vortex in hover to perform betterAirborne insects generate a leading edge vortex when they flap their wings. This coherent vortex is a low pressure region that enhances the lift of flapping wings compared to fixed wings. Insect…Alexander Gehrke, Karen Mulleners·Oct 2, 2024SaveLearn
The effect of gravity on bubble-particle collisions in turbulenceBubble-particle collisions in turbulence are key to the froth flotation process that is widely employed industrially to separate hydrophobic from hydrophilic materials. In our previous study (Chan et…Timothy T. K. Chan, Linfeng Jiang, Dominik Krug·Oct 2, 2024SaveLearn
Reduced Representations of Rayleigh-B\'enard Flows via AutoencodersWe analyzed the performance of Convolutional Autoencoders in generating reduced-order representations the temperature field of 2D Rayleigh-B\'enard flows at Pr=1 and Rayleigh numbers extending from…Melisa Y. Vinograd, Patricio Clark di Leoni·Oct 2, 2024SaveLearn
Cascades and Kolmogorov's lognormal scaling in two-dimensional bacterial turbulenceCollective movements of bacteria exhibit a remarkable pattern of turbulence-like vortices, in which the Richardson cascade plays an important role. In this work, we examine the energy and enstrophy…Yongxiang Huang·Oct 2, 2024SaveLearn
The Sound Radiated by Tip Clearances Submerged in a Boundary LayerThe present study investigates the behaviour of the far-field sound radiated by low Mach number tip clearance flow induced by placing a stationary cambered airfoil adjacent to a stationary wall. The…Manuj Awasthi, Danielle Moreau, Paul Croaker et al.·Oct 2, 2024SaveLearn
Towards eliminating the nonlinear Kelvin wakeThe nonlinear disturbance caused by a localised forcing moving at constant speed on the free surface of a liquid of finite depth is investigated using the forced Kadometsev-Petviashvili equation. The…Jack Keeler, Benjamin Binder, Mark Blyth·Oct 2, 2024SaveLearn
Effect of span size in Scale Resolving Simulations of airfoil stall and post-stallIn aerodynamic design, the use of Computational Fluid Dynamics (CFD) tools has long relied on Reynolds-Averaged Navier-Stokes (RANS) and Unsteady RANS (URANS) turbulence models. However, these…Francesco Mario D'Afiero, Renato Tognaccini, Gianluca Iaccarino·Oct 2, 2024SaveLearn
Role of triad interactions in spectral evolution of surface gravity waves in deep waterIt is generally accepted that the evolution of deep-water surface gravity wave spectrum is governed by quartet resonant and quasi-resonant interactions. However, it has also been reported in both…Zhou Zhang, Yulin Pan·Oct 2, 2024SaveLearn
Attenuation mechanism of wall-bounded turbulence by heavy finite-size particlesTo elucidate the attenuation mechanism of wall-bounded turbulence due to heavy small particles, we conduct direct numerical simulations (DNS) of turbulent channel flow laden with finite-size solid…Yutaro Motoori, Susumu Goto·Oct 2, 2024SaveLearn