Torque in a Running Turbine Engine

Is there a torque on the engine mounts of a running turbine engine?
A jet engine in an aircraft, or a marine propulsion unit in a ship?
Let's take a look at how all this stuff does what it does.

[oscarzt]

5252 is 1/60th of 33000 because the definition of 1 horsepower is 33, 000 foot pounds per hour and we calculate horsepower from a 'per minute' unit.

[josh]

Thanks for another insightful video, never really thought about how the rotational energies cancel themselves out

[russcole]

Nicely and very simplely explained. Well done. My brain was able to keep up. Thank you Jet Jesus

[SkyhawkSteve]

Another interesting video! Thanks for all of the work to keep us nerdy fans entertained.

[weltrettung]

What Art Arfons might be talking about, is the torque that is exerted, when the car is steering. The engine might not exert any torque when running in a straight line, but when the the rotor is forced to turn with the car the rotor will create massive torrque 90 degrees perpendicular to the turn axis (i think) due to precession. Or maybe he was just confused who knows.

[fredbugden]

Great video, something I've always wondered and never thought I'd get a layman's answer. Well done.

[willleader]

Your breakdown of the static equilibrium of a jet engine and internal torque cancelling got me thinking about how to express the way this works. The conclusion I came to is that the reaction torque of a jet engine is proportional to the mass flow of the engine and its swirl delta from inlet to exhaust. The swirl delta is never zero, but its very small in a well designed engine because the swirl from the compressor stages is reversed by the turbine stages. Thinking about it this way made the most sense to me, because stators and guide vanes do exert forces on the case, but it doesn't fully explain how the net torque generated by work done on the air is zero. It makes more sense when you account for what the mass flow is doing and the swirl direction change. Hope this helps someone else scratching their head.

[iainmarlatt]

Thank you for the video, my train of thought was on the right path. Sorry, I could have worded my question better. Nailed it sir!

[greghelms]

Very nice J. I knew the numbers were huge but never thought about the balance. Always wondered how engineers made nacelles and “hangers” off the wings for them so strong. Now I know.

[grahamj]

Excellent explanation, AgentJayZ, of the torque transmission through both the rotating and static components of an engine.
Externally, there is one simple way of determining whether there will be any torque reaction at the engine mounting trunnions of a turbojet or turbofan. If there is any swirl in the exhaust, there must be some torque loading applied to the trunnions. At an engine's design point, typically and ideally, there should be no swirl. Off design, there may be some swirl and, consequently, some torque reaction.
To answer another comment, there must be a torque reaction on the mounts for a turboprop because of the propeller - unless, of course, it has contra-rotating props.
PS However, we haven't specifically addressed the gyroscopic effects of the engine's rotor(s) when the aircraft (eg) rotates at take-off or turns in flight. The engine mountings must, of course, take some gyro loads during such manoeuvres (Brit spelling!). However, I've never had any comments about an appreciable 'resistance' from the aircraft by any pilots, even in high 'G' turns. Having said this, the Pegasus in the Harrier was specifically designed with contra-rotating spools to cancel out gyroscopic effects in the hover - and my team designed the new fan for the last mark of the Harrier II.
My recollection is that apart from stressing the mountings for (eg) 9G, the other limiting case was if the aircraft entered a flat spin, when the gyro loads could be large.

[jehanzebkhan]

Thank you Agent JayZ. That is a great explanation. A follow up question would be for a Turbo fan or Turbo Prop, is there any torque because now we have added another component which is outside the core engine. I would think yes but would like to hear your thoughts

[albertovelazquez]

HI, I am ALBERTO FROM PONCE, PUERTO RICO U.S.A.. Yor all right the torque and compression is very important for work the TURBINE EXCELLENT, I work in BAY CITY, MICHIGAN FOR Pratt and whitney, I learning a lot, Today I am retired in P.R.

[bobqzzi]

Nice video
FYI, automobile combustion engines, with few exceptions, turn clockwise when viewed from the balancer end.

[bensmith]

Omg, I had no idea porn bots are the first to post comments now. At least they're generically positive.

[Phantom]

Thinking the accessory gearbox and components also add to inertia balance/counterbalance and gyro effect as well. Still a low net effect though, but something to consider.

[sharg]

Youtube's motto: If it works*, fiddle with it.
*Works, here "gives the users what they want".

[alanalpert]

Isn't it true that 2/3 of the energy is used to turn the compressor and 1/3 is left for the LPT? Wouldn't this change the calculations for the torque on each shaft?

[Mentaculus]

OUTPUT is 33, 600 shp, so that torque would be on the gas generator output shaft (is that right? Power turbine speed @ 3600 rpm or maybe 3000 rpm). How much horsepower is generated to turn the compressor which was running at 9000 RPM? So two different torques on two different shafts maybe?

[mynamedoesntmatter]

Now you got me thinking about the torque a power turbine produces. Does it actually calculate the same way (hp/rpm x5252) or is there some kind of caveat to that? I’d imagine due to the way turbines build power, the torque is also relatively low all the way til 85-100% RPM and then it just takes off.

[jayman_gsr]

Only 7 minutes in but the only times the mounts would see torque would be when the engine is increasing or decreasing rpm? Once "idling" or rpm has stabilized the torque on the mounts would be small. I wonder what would happen lighting one without being mounted....