Building a Device with Vertical Pipe and Stepper Motor - Help Needed

[ytcat]

Hello.

Im bilding a device.

I have 1m vertical pipe with fan in the bottom and stepper motor at the top with sliding ping

pong ball in it.

(pipe d=45mm, ball d=40mm 2.7g)

Stepper controls ping pong high in the pipe.

The device is working but mehanics is not my aria at all so it is very difficult to me to

calculate all of it.

I have 25 CFM fan that located a couple mm under the pipe that working at a constant

rate, my question is how I can calculate using Bernoulli or Stocks laws if some

of the airflow is getting out from the space between the fan and the tube.

Also how can I calculate the pressures ratio if I have turbulence on the sides of the ball.

Please help.

 

[Illmatic1]

To calculate the air flow escaping from the space between the fan and the tube, you can use Bernoulli's equation. This equation states that the total energy of a flowing fluid is conserved along a streamline. You will need to measure the pressure and velocity of the air at two points along the streamline (one point being in the space between the fan and the tube and the other point being outside of this space). The difference in pressure between these two points can then be used to calculate the mass flow rate of air escaping from the space.To calculate the pressures ratio when there is turbulence on the sides of the ball, you can use a Stokes-Law calculation. This calculation is based on the drag force exerted by the ball on the surrounding air. You will need to measure the velocity of the ball and the viscosity of the fluid (air) to calculate the drag force. Once you have the drag force, you can then calculate the pressure ratio by dividing the drag force by the area of the ball.