#artinscience

Reflection of St. Luke’s Church (The Bombed-Out Church) in cyanotype from photo I took on Sunday @artinsciencema • #artinscience #cyanotype #ilovemymastersprogram (at John Lennon Art and Design Building) https://www.instagram.com/p/BqKGnvPHsyE/?utm_source=ig_tumblr_share&igshid=rqhactyj9ohb

“Turbulence is the most important unsolved problem of classical physics” said Feynman and remain an active field of current research. In a recent study Cardesa et al. made tremendous progress in observing the way turbulence works. The main theory of turbulence was proposed by the Russian mathematician and physicist Andrei Kolmogorov in the early 1940s. In his picture the energy spreads from large swirls to smaller eddies nearby till reaching a critical scale at which the viscous effects become important and dissipate the energy in heat. This “cascade of energy” explains how even low viscosity fluid like gazes (air) are able to dissipate rapidly energy. Onsager (one of the geniuses of the 1940s that even Feynman found intimidating to talk to) announced in 1949 that even in the absence of viscosity a fluid could in certain cases dissipates energy through turbulence: “a shocking idea” that was proven right mathematically in a recent paper of Isett (2016) but in a rather unrealistic flow (a more realistic case was proposed by Buckmaster et al. in 2017). The picture shows a drawing of Leonardo da Vinci on the movement of water showing with astonishing details the turbulent structures, the swirls and eddies. Sources: Castelvecchi, Mysteries of turbulence unravelled, Nature Comm. 548 (2017) Cardesa, Vela-Martin, Jimenez, The turbulence cascade in five dimensions, Science, 2017 Isett, A proof of Onsager’s conjecture (2016) https://arxiv.org/abs/1608.08301 Source image: image extracted from Lavin, Leonardo’s watery chaos (1993) #nakedfluiddynamics #fluiddynamics #fluidmechanics #physics #physique #scienceisart #science #artinscience #fluidartgallery #beautiful #picoftheday #awesome #turbulence #complex #complexphysics #chaos “When I meet God, I am going to ask him two questions: Why relativity ? And why turbulence ? I really believe he will have an answer for the first.” said Heisenberg.

Highspeed impact of small hydrophobic objects can generate several interesting physical phenomena (Rayleigh-Plateau instability leading to pinch of the air cavity, water curtain sealing which leads to Rayleight-Taylor instability). Here, the authors looked at the water entry of a dense millimetric sphere with a highspeed camera. The frames are separated by 1.9 ms. The 1mm radius sphere is coated to be hydrophobic and impact the water at 540cm/s. At the impact a splash forms at the surface and close inward sealing the air cavity which detaches from the surface and sinks with the spheres. The air being lighter than water, on top of the cavity there is water above (a bit like when you flip a glass of water). A Rayleigh-Taylor Instability arises and is clearly visible in a jet like form. In the mean time the  cavity pinches off due to surface tension.  The jet produced by the instability will then meet the end of the broken cavity and generate an under water splash. These events repeat with smaller bubbles. Reference: The water-entry cavity formed by low Bond number impacts,Jeffrey M. Aristoff, Tadd T. Truscott, Alexandra H. Techet and John W. M. Bush, Phys. of Fluids, 20 (2008) See also: Water entry of small hydrophobic spheres, Jeffrey M. Aristoff and John W. M. Bush, J. Fluid Mech., 619, (2009) #nakedfluiddynamics #fluiddynamics #fluidmechanics #physics #physique #splash #waterentry #waterimages #waterimpact #softmatter #scienceisart #science #artinscience #fluidartgallery #beautiful #picoftheday #awesome #mindblown #picoftheweek

Minimalist science poster #scienceFTW #artinscience #bluelight #DNA

Waves are reflected and transmitted when they interact with a submerged plate. Vortex shedding affects significantly the linear potential prediction by dissipating large amount of energy. It also affects the mean velocity field. This picture shows a long time exposition picture of the shore side of the submerged plate. The fluid is seeded with buoyant particles lighten by a pulse laser. The long exposition enables to see the particle path. Vortices are clearly visible. A clockwise rotating vortex on the top of the plate and two counter rotative vortices advected toward the bottom of the tank. Credit: Brossard groups for this picture and special thanks to Gaële Perret for sending me this beautiful picture. For more detail on it please refer to: A. Poupardin, G. Perret, G. Pinon, N. Bourneton, E. Rivoalen , J. Brossard, Vortex kinematic around a submerged plate under water waves. Part I: Experimental analysis, E. J. of Mech B/Fluids (2012) G. Pinon, G. Perret, L. Cao, A. Poupardin, J. Brossard, E. Rivoalen, Vortex kinematics around a submerged plate under water waves. Part II : Numerical computations, E. J. of Mech B/Fluids (2016) #nakedfluiddynamics #fluiddynamics #fluidmechanics #physics #physique #waves #waterwaves #piv #breakwater #scienceisart #science #artinscience #fluidartgallery #beautiful #picoftheday #awesome #mindblown

Science is not always as complex as it seems. For instance here this is how small drops are created in an oil bath by plunging a simple toothpick and rapidly taking it out! Note the drop does not merge back (coalesces) in the oil bath due to a small air layer and surface tension. Credits: Carmigniani, Lapointe , Symon & McKeon, Influence of a local change of depth on the behavior of walking drops, ETFS 2013 #science #amazing #slowmotion #picoftheday #fluiddynamics #drops #art #scienceandart #artinscience #physics #highspeedcamera #photronsa4 #follow #like #awesome #beautiful