Dynamic Self Organisation of Ferrofluid

Dynamic Self Organisation of Ferrofluid
In this experiment Ferrofluid shows a continuos cycle of diffusion and concentration. Some thinner is added to a drop of ferrofluid which is on a dish over a permanent magnet. When spreading out, the thinner takes a low concentration of ferrofluid with it, too low to be bound to the magnet.

The flow is limited by the wetting border of the spot. Increased evaporation increases the flow towards the border. At the end of its way, the concentration of the fluid is increased by evaporation, in a circle around the centre.

At the according level of concentration the fluid on the circle joins to Rosensweig peaks, dots of further increased concentration. These peaks are sufficiently attracted to move back against the continuos outward flow, leaving a track of ferrofluid behind.

Near the centre the peaks are repelled by the centre material which has the same magnetic orientation. In the flowing environment, with much thinner, the Rosensweig peaks "tunnel" to the centre, while the rest of the trace is repelled and partly washed away.

With decreasing thinner and higher concentration, peaks are formed in the centre. The material is regrouped with new material returning to the centre. At the end the peaks at the centre stay separate and more peaks are joining.

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Dynamische Selbstorganisation von Ferrofluid

In diesem Experiment befindet sich Ferrofluid in einem kontinuierlichem Prozess von Diffusion und Konzentration. Einem Tropfen Ferrofluid, der sich auf einer Schale über einem Magneten befindet, wird etwas Verdünner hinzugefügt. Beim Ausbreiten führt der Verdünner etwas Ferrofluid mit sich, zu wenig um von Magneten festgehalten zu werden.

Die Ausbreitung erfolgt bis zur Benetzungsgrenze. Eine erhöhte Verdunstung verstärkt dabei den Fluss nach außen. Am Ende des Wegs, auf einem Kreis um das Zentrum, wird die Konzentration der Flüssigkeit durch die Verdunstung erhöht.

Bei der entsprechenden Konzentration bilden sich auf diesem Kreis Rosensweig Spitzen, Flecken mit weiter erhöhter Konzentration. Diese Flecken werden dann ausreichend stark angezogen, um gegen den kontinuierlichen, nach außen gerichteten Fluss, zur Mitte zurückzukehren. Sie hinterlassen dabei eine Spur von Ferrofluid.

In der Nähe des Zentrums werden die Flecken vom Material im Zentrum abgestoßen, das die gleiche magnetische Orientierung hat. In der fließenden Umgebung mit viel Verdünner können die Rosensweig Spitzen zum Zentrum „tunneln", wobei ihre Spur abgestoßen und zum Teil weggespült wird.

Mit der Abnahme des Verdünners und zunehmender Konzentration bilden sich im Zentrum Spitzen. Das Material im Zentrum wird mit neuem, zurückfließendem Material neu zu Spitzen gruppiert. Zum Schluss bleiben die Spitzen im Zentrum getrennt und neues Material bildet weitere Spitzen.

Category:

Science & Technology

Tags:

• Ferrofluid
• Nano
• Magnet
• Fluid
• Physics
• Experiment
• Dynamic
• Self
• Organisation

[pisseddotcom]

Every video about chemistry and/or physics I've seen since grammar school has this weird synthetizer kind of music in the background that sounds like if it was made by someone intoxicated with a very large dose of LSD. The question is: is it only accident that whenever chemists are involved in making educational videos, the music always sounds so psychedelic?

[manf1234]

I think in the beginning there was a simple melody in the background, I just did some time lapse, compression and format conversions to optimize the upload, and you tube also has to fit it in. It could not be backwards, at least not the video part, did you check that? :o)

[myrtlered]

what is the thinner?

[manf1234]

Pentane

[BloodyNeko12]

kinda looked like sperm going to a egg

[Warcraftian]

looks like sperm trying to fertilize an egg

[AcidSkiffle1988]

sperm

[zillaje]

looks like an eyeball

[vechmaster]

Hmmm make an optical sensor to hold it and to make it see then u need to make a frame for the mouth and te rest if te body like make te hands out of mabey a putty like substance

[manologrhacker]

bloody eye

[fknrdcls]

This is easily one of the most interesting things I've seen done with ferrofluid. Have to keep reminding yourself it's not a biological process.

[tuloski]

Are you trying to give birth to Magneto (X-man)?

[THE0GUVNAH]

I was waiting for Ben Stein to give a spot about red, itchy eyes but, this is science and we all know about Ben Stein and science...

[lisamariestube]

@pisseddotcom I wonder that too. In Highschool there was a video about fungus that was SOOOO trippy.

[krononomikon]

IT'S STARING AT ME!!!!!!!!

[sam12321able]

looks like an eye