Airflow Over a Spinning Sphere

[nerobro]

I got this link from the tinker's guild.

http://www.ansys.com/industry/fsi/showcase/pingpong.htm

It's a ping pong ball, I think it's a good analogy to a paintball.

[i heart my mag]

its a good analogy if the pball spins constantly in on the same axis at a constant rate......i dunno....does it?

[FooTemps]

Originally posted by i heart my mag
its a good analogy if the pball spins constantly in on the same axis at a constant rate......i dunno....does it?

it's got backspin, aka it's a paintball that just flew out of a tippmann flatline barrel.

[hitech]

It is a very good start. There is very little data on the airflow past a sphere, let alone a spinning sphere. I found it very interesting.

[SLICEnDICE]

You are welcome

I found the spinning sphere in my quest for facts on paintball in flight, or other round things flying through the air. I posted it over at docs form and then someone posted it here before I got the chance to.

[hitech]

Re: You are welcome

Originally posted by SLICEnDICE
I found the spinning sphere in my quest for facts on paintball in flight, or other round things flying through the air.

Have you found any additional research on vortex shedding on spheres at high R numbers?

[AGD]

Nice animation! The flow is not the same as a paintball though.

AGD

[SLICEnDICE]

Some other data

Enjoy, Re=140

[hitech]

Is that a sphere or a cylinder?

[SLICEnDICE]

Cylinder

I put it up because I remember a while back there was discuession about paintball accurcy. I believe there was mention of a wake or wave behind the ball limiting its accurcy. This was just to give a color visual of what that may look like.

[hitech]

Re: Cylinder

Originally posted by SLICEnDICE
I put it up because I remember a while back there was discuession about paintball accurcy. I believe there was mention of a wake or wave behind the ball limiting its accurcy. This was just to give a color visual of what that may look like.

Cool. I only asked because it looked like wake behind a cylinder. A sphere has a somewhat similar wake, but there are VERY FEW pictures of it. It seems the majority of the research has been on cylinders.

[nerobro]

making the leap from the 2d air behind a cylinder to the 3d air behind a sphere is a big one. but... it comes out the same.... it just looks funny.