System analysis of a centrifuge

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Vorrawit
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Homework Statement



Initial training involves a slow onset rate (1 g/s) run up to a maximum of 9 g’s. After these initial runs, a rapid onset rate (ROR) of 6 g/s is typically performed; this is for high performance fighters. Finally, a Tactical Aircraft Combat Maneuver (TACM) may be performed. The sequence consisted of a Rapid Onset (6 g/s onset), beginning at 2g. The centrifuge then goes to 9g for 5 seconds, 5g for 1 second, then 5 seconds at 8g, 2 seconds at 4g, and 1.5g for 3 seconds. The centrifuge was finally brought to a complete stop.
You are an engineer in the centrifuge design team. You are asked to determine what type of torque will be required to generate TACM. Also calculate how much force will be placed on the centrifuge’s drive shaft. To do the calculation break this problem into subtasks:
1. Find the angular velocity required to produce the required g levels.
2. Determine the angular acceleration need to achieve a 6 g/s onset rate
3. Determine the torque needed to produce this angular acceleration.
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Homework Equations

 
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Vorrawit said:

Homework Statement



Initial training involves a slow onset rate (1 g/s) run up to a maximum of 9 g’s. After these initial runs, a rapid onset rate (ROR) of 6 g/s is typically performed; this is for high performance fighters. Finally, a Tactical Aircraft Combat Maneuver (TACM) may be performed. The sequence consisted of a Rapid Onset (6 g/s onset), beginning at 2g. The centrifuge then goes to 9g for 5 seconds, 5g for 1 second, then 5 seconds at 8g, 2 seconds at 4g, and 1.5g for 3 seconds. The centrifuge was finally brought to a complete stop.
You are an engineer in the centrifuge design team. You are asked to determine what type of torque will be required to generate TACM. Also calculate how much force will be placed on the centrifuge’s drive shaft. To do the calculation break this problem into subtasks:
1. Find the angular velocity required to produce the required g levels.
2. Determine the angular acceleration need to achieve a 6 g/s onset rate
3. Determine the torque needed to produce this angular acceleration.
[/B]

Homework Equations

Welcome to PF Vorrawit!

What is the direction of the force experienced by a body at the end of the centrifuge? (hint: consider the prefix "centri" in centrifuge). Can you express that force as a function of angular speed and radius? Consider how rapidly that force has to change. What does that tell you about the rate of change of angular speed (i.e angular acceleration)?

If you can answer those questions, that should give you a good start to answering the questions.

AM
 
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There are two accelerations at play. Besides the radial acceleration, tangential acceleration should also be taken into account.
 
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Start simple. Calculate angular speed required for 1g. Correct: standing still is good enough. Now √2 g , etc.
Make a drawing of the sequences.
 
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