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Something every THT'r can agree upon

Old 04-10-2020, 09:31 AM
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Default Something every THT'r can agree upon

But maybe not.

A rocket motor propulsion device produces thrust with no torque whatsoever. Yea or nay?

Last edited by alloyboy; 04-11-2020 at 10:22 AM.
Old 04-10-2020, 10:08 AM
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No twisting force = no torque
Old 04-10-2020, 11:15 AM
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a rocket is not a motor .
Old 04-10-2020, 11:18 AM
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Just like my neighbors RAV4
Old 04-10-2020, 11:21 AM
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Yep the Space Shuttle produced about 16,000,000 horsepower at "lit full wick" take off! But with no rotating mass/cranktrain there is no torque.
Old 04-10-2020, 11:24 AM
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All noob questions must be accompanied by a pic of girlfriend or wife, whomever is hotter.
Old 04-10-2020, 11:38 AM
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That depends...due to variances with the fuel delivery within the engine (unstable flame / flame rotation) or inconsistencies in the nozzle there is typically a torque applied to one side or the other of the housing or attached vehicle. It can be managed with an adjustable or gimballed nozzle, but a torque reaction can be present.
​​​
So technically a rocket can produce both, though not in the fashion you're likely talking about.
Old 04-10-2020, 11:39 AM
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Originally Posted by 1breakinit View Post
a rocket is not a motor .
This is the truth!
Old 04-10-2020, 11:45 AM
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they produce thrust. no torque
Old 04-10-2020, 11:51 AM
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Sometimes I fire off like a rocket, sometimes I sputter like an motor, but as long I
as it's still going off, I'm happy.
Old 04-10-2020, 11:56 AM
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Originally Posted by whitey436 View Post
All noob questions must be accompanied by a pic of girlfriend or wife.
Or both...
Old 04-10-2020, 12:14 PM
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Originally Posted by 1breakinit View Post
a rocket is not a motor .
Absolutely correct. It is an "engine" not a "motor".

But the same applies to all those things hanging on the transoms of so many boats, almost always referred to as 'motors' on this site. But they are internal combustion ENGINES, not electric or rocket MOTORS.

Just sayin'
Old 04-10-2020, 12:49 PM
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Originally Posted by ocnslr View Post
But the same applies to all those things hanging on the transoms of so many boats, almost always referred to as 'motors' on this site. But they are internal combustion ENGINES, not electric or rocket MOTORS.

Just sayin'
I tend to mean the whole outboard when I say "motor" and only the powerhead when I say "engine". But that's just me.
Old 04-10-2020, 12:51 PM
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Originally Posted by alloyboy View Post
But maybe not.

A rocket motor produces thrust with no torque whatsoever. Yea or nay?
2 stroke or 4 stroke?
Old 04-10-2020, 12:53 PM
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jet or rocket ..
Old 04-10-2020, 01:02 PM
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Originally Posted by alloyboy View Post
But maybe not.

A rocket motor produces thrust with no torque whatsoever. Yea or nay?
The Space Shuttle Main Engine fuel turbopump weighs approximately the same as a V-8 auto- mobile engine, but develops 310 times the brake horsepower and develops as much torque as 18 V-8 auto engines. The main shaft of the turbopump rotates at 37,000 rpm—a car operating at 60 mph runs at 2,000 rpm.
Old 04-10-2020, 01:08 PM
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A rocket engine can produce 1000’s of ft/lb of torque . It just depends on what you do with the thrust
Old 04-10-2020, 01:15 PM
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Originally Posted by lobsdiver1 View Post
The Space Shuttle Main Engine fuel turbopump weighs approximately the same as a V-8 auto- mobile engine, but develops 310 times the brake horsepower and develops as much torque as 18 V-8 auto engines. The main shaft of the turbopump rotates at 37,000 rpm—a car operating at 60 mph runs at 2,000 rpm.
I used to repair these turbo pumps. A crazy amount of technology in those, a very powerful turbine and pump, in a very very small space. Pretty much a one use item, used for one launch, then rebuilt completely. There's actually several of them, pumping oxidizer and fuel separately.
Old 04-10-2020, 01:56 PM
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Old 04-10-2020, 02:57 PM
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Originally Posted by 1breakinit View Post
a rocket is not a motor .
ding ding

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