Maximizing Rotary Projectile Motion: Finding Distance and Path Diameter

AI Thread Summary
The discussion focuses on a rotating disk with nozzles that release particles tangentially, and the challenge is to determine the maximum horizontal distance and diameter of the circular path the particles will take after leaving the disk. The effects of air resistance from the enclosure are considered, as they may impact the trajectory of the particles. It is suggested to define two sets of unit vectors—one inertially fixed and one fixed to the rotating disk—to analyze the motion accurately. The conversation also highlights the importance of applying force and moment equations to derive the equations of motion, which may result in non-linear differential equations. Understanding these dynamics is crucial to prevent the particles from hitting the enclosure walls.
elmariachi
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Hi all,
the problem i have is that there is a rotating disk with nozzles on its circumference. a material is being pushed into this rotating disk/plate and its being released from the nozzles tangentially. The disk is rotating with a certain rpm such that the angular velocity of the particle just leaving the disk is w*r.
I believe that the particle from the disk will follow a circular path in the direction of the rotating disk. The rotating disk is enclosed within a room of specified length with air blown from the bottom of this enclosure such that the air resists the particles coming out of the disk.
I wanted to make sure that the particles thrown out of the disk don't go and hit the walls of the enclosure.I want to know, how can I find the longest horizontal distance , the material will travel just after leaving the disk and How big a circular path will it take (diameter).I will appreciate the help.

thanks
 
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You need to start this problem defining two sets of unit vectors, a set that is inertially fixed and a set that is fixed to the rotating disc. In this case if we are in a horizontal plane we can neglect the effects of gravity since this disc is just traveling on the horizontal surface. I've done this problem with a rod in which there was one thruster and one end always thrusting tangential to linear velocity of the tip. If you apply F = ma, the only force you have acting is the thrust in the tangential direction. However, in your case you have a disc so there may be multiple forces, but note that if you have symmetry in these forces the disc will only rotate because while the net moment is non-zero, the net force will be zero. If you are familiar with SIMULINK i can send you my .mdl file so you can get an idea of how your EOMs should look.

Ooops forgot to add that you will also need to apply a moment equation to find a state equation for theta (or whatever you use for your angular measurement).

Unfortunately in the end you should end up with a set of non-linear DE's :(
 
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