fuckyeahfluiddynamics

fuckyeahfluiddynamics:

Artist Charles Sowers creates exhibits and public art focused on illuminating natural phenomenon that might otherwise go unnoticed, and much of his work features fluid dynamics directly or indirectly.  “Windswept” and “Wave Wall” are both outdoor exhibits that show undulations and vortices corresponding to local wind flow. Other pieces explore ferrofluids through magnetic mazes or feature foggy turbulence.  My own favorite, “Drip Chamber”, oozes with viscous fluids whose dripping forms patterns reminiscent of convection cells. Be sure to check out his website for videos of the exhibits in action. (Photo credits: Charles Sowers; submitted by rreis)

Cool.

fuckyeahfluiddynamics

fuckyeahfluiddynamics:

Hydraulic jumps occur when a fast-moving fluid enters a region of slow-moving fluid and transfers its kinetic energy into potential energy by increasing its elevation.  For a steady falling jet, this usually causes the formation of a circular hydraulic jump—that distinctive ring you see in the bottom of your kitchen sink. But circles aren’t the only shape a hydraulic jump can take, particularly in more viscous fluids than water. In these fluids, surface tension instabilities can break the symmetry of the hydraulic jump, leading to an array of polygonal and clover-like shapes. (Photo credits: J. W. M. Bush et al.)

One cool thing about getting older is that I learn the names of things that fascinated me as a child.

fuckyeahfluiddynamics

fuckyeahfluiddynamics:

Part of the beauty of numerical simulation is its ability to explore the physics of a situation that would difficult or impossible to create experimentally. Here the Rayleigh-Taylor instability—which occurs when a heavier fluid sits atop a lighter fluid—is simulated in two-dimensions. Viscosity and diffusion are set extremely low in the simulation; this is why we see intricate fractal-like structures at many scales rather than the simulation quickly fading into gray. (The low diffusion is also what causes the numerical instabilities in the last couple seconds of video.) The final result is both physics and art. (Video credit: Mark Stock)

fuckyeahfluiddynamics

fuckyeahfluiddynamics:

Like the javelin, the discus throw is an athletic event dating back to the ancient Olympics.  Competitors are limited to a 2.5 m circle from which they throw, leading to the sometimes elaborate forms used by athletes to generate a large velocity and angular momentum upon release. The flight of the discus is significantly dependent on aerodynamics, as the discus flies at an angle of attack. Spin helps stabilize its flight both dynamically and by creating a turbulent boundary layer along the surface which helps prevent separation and stall. Unlike many other events, a headwind is actually advantageous in the discus throw because it increases the relative velocity between the airflow and the discus, thereby increasing lift. The headwind also increases the drag force on the discus, but research shows the benefits of the increased lift outweigh the effects of increased drag, so much so that a discus flies further in air than it would in a vacuum. (Photo credits: P Kopczynski, Wiki Commons, EPA/K Okten)

FYFD is celebrating the Olympics by featuring the fluid dynamics of sports. Check out our previous posts, including why corner kicks swerve, what makes a pool fast, how an arrow flies, and how divers avoid splash.

The funny thing is, I willmention the fact that a discus will fly further in air than in vacuum at a party.

That let’s you know the sort of parties I go to.

fuckyeahfluiddynamics

fuckyeahfluiddynamics:

Few Olympic events can boast as long as history as the javelin. Though the event has existed since the ancient Olympics, humans and our ancestors have been throwing spears for hundreds of millennia. But today’s javelin, oddly enough, is designed so that it cannot be thrown as far as those that came before. After a world record throw in 1984 that nearly reached the edge of the track, the sport’s governing body authorized new rules that shifted the weight of the javelin forward, causing the center of mass of the javelin to lie in front of its center of pressure.  This causes the javelin to tip forward in flight, ensuring it will land nose down. Simultaneously, they made changes to the nose of the javelin to reduce its lift during flight, resulting in a javelin that flies only 90% of the previous distance. Since then manufacturers have introduced other innovations to try to increase the javelin’s flight, such as a roughened tail to prevent flow separation, only to later have these changes banned.  (Photo credits: Getty Images, Zeenews)

FYFD is celebrating the Olympics by featuring the fluid dynamics of sport. Check out some of our previous posts, including what makes a pool fast, how divers reduce splash, how cyclists get “aero”, and how rowers overcome drag.

intothecontinuum
intothecontinuum:


In July 1967, astronomers at the Cavendish Laboratory in Cambridge, observed an unidentified radio signal from interstellar space, which flashed periodically every 1.33730 seconds. This object flashed with such regularity that it was accurate enough to be used as a clock and only be off by one part in a hundred million.
It was eventually determined that this was the first discovery of a pulsar, CP-1919.  This is an object that has about the same mass as the Sun, but is the size of the San Francisco Bay at its widest (~20 kilometers) that is rotating so fast that its emitting a beam of light towards Earth like a strobing light house! Pulsars are neutron stars that are formed from the remnants of a massive star when it experiences stellar death.
A hand drawn graph plotted in the style of a waterfall plot, in the Cambridge Encyclopedia of Astronomy, was later arguably more renown for its use on the cover of the album “Unknown Pleasures”  by 1970s English band Joy Division.
Some even managed to point out the resemblance of this plot to some other waterfall plot gifs.
Also, two days ago today was Joy Divisions singer’s, Ian Curtis, birthday!
Mathematica code:
R[n_] := (SeedRandom[n]; RandomReal[])ListAnimate[ Table[  Show[  Table[   Plot[    80 - m    + .2*Sin[2 Pi*R[6*m]             + Sum[4*Sin[2 Pi*R[4*m] + t + R[2 n*m]*2 Pi]*                  Exp[-(.3*x + 30 - 1*100*R[2 n*m])^2/20],               {n, 1, 30, 1}]]    + Sum[3(1 + R[3*n*m])*Abs[Sin[t + R[n*m]*2 Pi]]*          Exp[-(x - 1*100*R[n*m])^2/20],      {n, 1, 4, 1}],  {x, -50, 150},   PlotStyle -> Directive[White, Thick],    PlotRange -> {{-50, 150}, {0, 85}},    Background -> Black, Filling -> Axis, FillingStyle -> Black, Axes -> False,    AspectRatio -> Full, ImageSize -> {500, 630}], {m, 1, 80, 1}]],{t, 0, 6.3*18/19, 6.3/19}],AnimationRunning -> False]


That is pretty neat.  I had no idea about the Joy Division connection.

intothecontinuum:

In July 1967, astronomers at the Cavendish Laboratory in Cambridge, observed an unidentified radio signal from interstellar space, which flashed periodically every 1.33730 seconds. This object flashed with such regularity that it was accurate enough to be used as a clock and only be off by one part in a hundred million.

It was eventually determined that this was the first discovery of a pulsar, CP-1919.  This is an object that has about the same mass as the Sun, but is the size of the San Francisco Bay at its widest (~20 kilometers) that is rotating so fast that its emitting a beam of light towards Earth like a strobing light house! Pulsars are neutron stars that are formed from the remnants of a massive star when it experiences stellar death.

A hand drawn graph plotted in the style of a waterfall plot, in the Cambridge Encyclopedia of Astronomy, was later arguably more renown for its use on the cover of the album “Unknown Pleasures”  by 1970s English band Joy Division.

Some even managed to point out the resemblance of this plot to some other waterfall plot gifs.

Also, two days ago today was Joy Divisions singer’s, Ian Curtis, birthday!

Mathematica code:

R[n_] := (SeedRandom[n]; RandomReal[])

ListAnimate[
Table[
Show[
Table[
Plot[
80 - m
 + .2*Sin[2 Pi*R[6*m]
+ Sum[4*Sin[2 Pi*R[4*m] + t + R[2 n*m]*2 Pi]*
Exp[-(.3*x + 30 - 1*100*R[2 n*m])^2/20],
{n, 1, 30, 1}]]
 + Sum[3(1 + R[3*n*m])*Abs[Sin[t + R[n*m]*2 Pi]]*
Exp[-(x - 1*100*R[n*m])^2/20],
{n, 1, 4, 1}],
  {x, -50, 150},
  PlotStyle -> Directive[White, Thick],
PlotRange -> {{-50, 150}, {0, 85}},
Background -> Black, Filling -> Axis, FillingStyle -> Black, Axes -> False,
AspectRatio -> Full, ImageSize -> {500, 630}],
 {m, 1, 80, 1}]],
{t, 0, 6.3*18/19, 6.3/19}],
AnimationRunning -> False]

That is pretty neat.  I had no idea about the Joy Division connection.

backwardinduction

backwardinduction:

Last night I was discussing the feminist values that my (all-girls, Catholic) high school tried so hard to instill in its students with Kelly and I began to grow upset as a realization dawned on me.

You see, this school integrated awareness of sexism and feminism into all of its coursework—or,…

Grad school shenanigans

I have been busy finalizing my grad school plans.  Things turned out a bit unexpectedly.  I will be getting a PhD in Electrical Engineering.  It is less of a jump from physics than it might appear.  I will basically be working on computational condensed matter physics.  I still hear the clarion call of particle physics, but condensed matter is cool too and is more employable.  Plus I am going to a top 10 engineering program and if I had stuck with physics I definitely would not have been at top a 10 program.