G-Forces on a Paintball

[nak81783]

AO,

I need some help. I can't find any data as to the g-forces on a paintball. I'm in desperate need of this information for a Fluid Mechanics project at school. Please let me know if anyone has any information on this. I have a calculated value, but it seems pretty far off.

I simply used kinematic equations to find acceleration. I used 0 ft/s as an initial velocity and 280 ft/s as a final velocity taking place over a distance of 4 inches. The acceleration found was then divided by the gravitational constant. Is this all there is to it?

Thanks,
Nathan

[craltal]

are you talking just about the forces inside a barrel, or for full flight?

Are you thinking of a 4" barrel? otherwise you are not using the complete story inside the barrel.

You have friction due to contact with the inside of the barrel (which will vary depending on the material of the barrel) as well as the air resistance experienced by the ball as it moves against the air.

gravity would not have as great an effect as you are propelling it in a horizontal vector and gravity will act in the vertical.

[IronCore]

did you get something like 3,804 g's?

[ThePixelGuru]

Assume about 8" for acceleration, and go from there.

[ScatterPlot]

8 inches seems a little high, don't you think? I'm thinking that the 4 he originally went with would be more applicable. After the first of the porting the air vents very rapidly, and there would be negligible accelleration from then on.

As for the comment on friction, etc., that doesn't matter. The g-forces felt by the paintball are going to be completely dependent upon the accelleration that the paintball feels.

Initial velocity is indeed zero, final being 280 fps: dv = 280 fps
Assuming constant accelleration, average velocity is 140 feet per second, going over 4 inches, or .333 feet, so a time of .00238 seconds: dt = .00238

a=dv/dt
a=117647 fps^2
g=32.2 fps (I think, close enough)
so g-force is something around 3654 g's.








I think.

[Gunther_mag_user]

It says something about that in toms tech tips.

http://www.automags.org/resource/tech/tomstech/01_barrel_eff.shtml

[nak81783]

Thanks and Sorry

Thanks for all of your help. I totally forgot I posted this until I checked my User CP today. For some reason I didn't get e-mail notification that replies were made to my post. I ended up with a 97% in the class.

Thanks Again,
Nathan