Vortex shedding from a circular cylinder

Vortex shedding mechanism from a circular cylinder. Experimental flow visualisation with hydrogen bubbles and a laser sheet in a water channel. By Gustavo Assi, London, March 2008.

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  Education

[Rajeev Nagotra]

Hi Gustavo. That's a very very impressive visualization indeed.

I wonder what the strength (amperes) of current and/or the voltage needed to produce this neat stream of hydrogen bubbles is. And, I think the bubbles are being produced intermittently and continuously. What is the time between two electric pulses in this case ?

Thanks.

[Gustavo Assi]

Hi,

I used four stainless steel wires... about 600mm long. The DC power supply was set to 60V, but you must have some control in order to cahnge the rate the bubbles are formed. You need small bubbles that will follow the flow, but still big enough to generate nice traces. There was no need to add salt in the water... London water is very hard already...

Cheers,

Gustavo

[bresslau]

I missed some music too... hehe. But great work, Guto!

[Gustavo Assi]

hehehe... soundtrack for you, Bress...

[ichiko dwita]

Iwas tryin to make a system to produce hydrogen like u do.

But the i've got the problem, could u tell how much ampere it consume.

Because i made an equipment use 100V and less than 0,1 Ampere, but the bubble of hydrogen just stuck in the wire.

Could u help me

Thanks

[Marco-Felipe King]

We'd like to make a light sheet too. How did you set yours up? Regards

[ihapub]

Was this experiment repeated with a trailing fin? If so, can a similar video be made available?

[slump75]

I have no understanding of this and yet I watched it twice. Very interesting things are just very interesting, I suppose.

[Slokos1]

Hey does anyone know how this is made/ set up can someone provide me with a link or something on how to make something like this for a presentation. i understand the basic "materials" he used to do this but I'm curious as to how its built/ operated. Any help would be appreciated.

[Brad1711]

Hmm I loved doing these labs.

[curva130r]

I love it!!!

Thanks for make it and upload it!!!

[xxlegolas]

Very cool means of visualizing the paths the gas bubbles are taking. It's like the next evolution of using a wind tunnel to study drag forces.

[tracksidetuning]

Este video foi uma bastante ajuda. Tava querendo ver como funciona uma Karman sensor num carro. Isso explica perfeitamente em minha mente. Obragado. Tambem este musica é mesmo sientifica. Haha