Answering a question about why it is so important to watch the temperature gauge for a turbine engine. It's the most important thing. More important than anything!
Пікірлер: 150
@addictedtoskiing273 жыл бұрын
Your work has inspired me to join the aviation industry. Just recently got my airframe license and about to wrap up my powerplant time. We just finished doing a mock inspection of a J34 in school. Thank you for your videos!
@AgentJayZ3 жыл бұрын
Thanks for making my day... and then some!
@ASJC273 жыл бұрын
It is interesting to note that the current king in terms of turbine inlet temperature is the PW F135 in the F-35 at 2260 K. At that temperature, about 70% of the oxygen in the combustors is burned, which is much higher than any other engine I've seen.
@AgentJayZ3 жыл бұрын
Where can I read more about that?
@ASJC273 жыл бұрын
@@AgentJayZ Here is an article from the American Society of Mechanical Engineers discussing the F135 and its record breaking temperature tolerance: asmedigitalcollection.asme.org/memagazineselect/article/129/04/34/366970/Fahrenheit-3-600Everywhere-You-Look-the-Gas. With this and the other specs of the engine (overall pressure ratio, bypass ratio, thrust...) the thermodynamic cycle calculation can be made to determine a lot about its operation. I used a professional gas turbine analysis software (GasTurb) to do these calculations. The result is that about 70% of the oxygen in the combustor must be combusted in order to reach this temperature. Another very interesting result is that with the afterburner fully engaged, nearly all of the air (>90%) is burned (that includes the ~30% remaining in the core flow plus the bypass flow). This engine is quite a monster.
@fuzzy1dk3 жыл бұрын
@@AgentJayZ a bit here: www.f-16.net/forum/viewtopic.php?t=14070
@walt80893 жыл бұрын
When our Unit converted from Recips to C-130E's in 1975 an Allison Rep gave a class and I remember him saying about over temp of TIT, that metal has a memory and never forgets.
@timwynn60793 жыл бұрын
This is the best explanation on turbine ITT, on ATRs we have to keep a watch out on ITT on Eng2 cause we use it as APU during ground operations when GPS is not available or A/C is required for commercial usage, when ITT hits near the cap due to tail wind bleed needs to be switched off immediately otherwise eng kablamo is to be expected.
@schwags19693 жыл бұрын
Always an informative video. Temperature is thing in my diesel powered world to.
@etravix3 жыл бұрын
Thanks for sharing and increasing my knowledge and understanding of things beyond my reading comprehension.
@perropipa9003 жыл бұрын
thank you for educating us
@CanadairCL443 жыл бұрын
Jay, TGT on the Tyne 515 used to reach > 680*c on startup. Any higher than 700*c, shut the fuel off and abort the start. Normal TGT in the cruise is between 550*c to 600*c. Loved the comment on the bucket!
@jasonlemon44913 жыл бұрын
Happy Labor day AgentJayZ! Is great to see you here today!
@phrodendekia3 жыл бұрын
Every time you show us your chart, you correct the velocity graph, that tells a lot 👌
@AgentJayZ3 жыл бұрын
An important part of learning is using multiple sources. Eventually you can see shortcomings in some of the books.
@Tailz3033 жыл бұрын
@@AgentJayZ i know you're probably not going to see this, but I want you to know that your videos have changed my life. Whenever im down, i come here to take my mind off of stuff. Thanks for that!
@markb17643 жыл бұрын
i believe ka-blammo is a technical term used by batman and robin
@khaledyousfi71603 жыл бұрын
Thanks for sharing I've been following you for more than 2 years, your videos are very helpful
@shainemaine12683 жыл бұрын
I love that engines compression system, a combination axial-centerfugal compressor
@mikesmith72493 жыл бұрын
AgentJayz, regarding the T56. Series 1, 2 and 2.5 T56 engine do in fact use TIT, however the series 3 and subsequent use TMT (turbine measured temperature) measured between stages 2 &3
@ParanoidBurritos3 жыл бұрын
Working on everyone's day off, huh? Thanks for the lecture, AgentJayZ!
@whoyoulookingatabs10283 жыл бұрын
8:14 something tells me Jay has tried it...
@icojb253 жыл бұрын
FWIW, designers are mostly interested in the TIT (turbine inlet temp) for maximising the cycle (thermodynamic) efficiency as well as preventing exceeding Tmax of the first row of blades (NGV's), while pilots are mostly interested in ITT and EGT, again primarily to prevent engine overheat (even though they're usually much different and lower than the TIT) but used more commonly because they're much more easily measured in the cooler downstream flow than in the hot zone immediately aft of the combustor. On the combustor pressure, the Brayton (turbine) cycle assumes heat addition (combustion) at constant pressure by design, (as opposed to say, the Otto (petrol) cycle, where heat is added at constant volume, ie when a piston is near TBC causing a spike in cylinder pressure) hence the nearly constant pressure in the combustion chamber. The small / gradual reduction in pressure shown in the diagram in the combustion chamber is actually mostly due to combustion loss (mostly turbulence needed for mixing the hot combusted air with the cooler dilution air, ensuring the working fluid entering the NGV is as uniform as possible). In a well designed machine, this is around 1% of the max combustion pressure.
@grahamj91013 жыл бұрын
Today, 15th September 2020, is acknowledged as the 80th anniversary of the Battle of Britain here in the UK. As Churchill said, "Never in the field of conflict was so much owed by so many to so few." At this moment, I'm watching a TV programme showing the restoration of a WWII Spitfire that suffered a forced landing and, yesterday evening, I watched an extended programme about the Spitfire (and the Hurricane) and the people who flew them, included the women of the ATA who delivered them from the factories to the squadrons.
@matteobuda29403 жыл бұрын
Hey would you please consider enabling the auto captioning option for your videos for those of us with hearing issues? Thanks
@AgentJayZ3 жыл бұрын
Auto generated captions have proven to be so inaccurate as to be misleading, and only add confusion. Every time I have tried them, I disapprove of the content. Sorry, the YT algorithms are not up to the job.
@richardreddick56813 жыл бұрын
before I retired we made f110 1st stage stators and F404 1st stators at Johnston Technology. A f110 had around 600 cooling holes on airfoils and inner and out bands. These all for creating a cooling film on part surface to minimize heat damage. I do have question for you. was ceramic coating on the blades of the original version of j79?
@AgentJayZ3 жыл бұрын
The original J79s most likely had no thermal barrier coatings. I have experience with the J79-8, -10, -11, -15, -17, and the -19. None of them had thermal barrier coatings anywhere, except the liners of the jet pipe on the afterburners.
@richardreddick56813 жыл бұрын
@@AgentJayZ it was what I was thinking. coating and cooling holes better super alloys all came later to increase power.
@annabobanaasmr84113 жыл бұрын
I've been looking for a channel like this for a while, I don't know if I'll get this indepth in my career, but I'm interning to be a mechanic rn
@donstor13 жыл бұрын
Great instruction, thank you.
@teacherinthailan64413 жыл бұрын
Fascinating! Cheers
@DeliveryMcGee3 жыл бұрын
"Catastrophic engine damage" I think the technical term is "engine-rich exhaust," or is that only for rockets?
@turbofanlover3 жыл бұрын
Outstanding vid.
@lathamsimpson61153 жыл бұрын
Love these videos
@rodgerball61493 жыл бұрын
AJZ - I always thought a demonstration of this was simply to pop out a torch. Seeing how the flame shoots out and how faster super heated flames are used to cut metal.
@Pitchlock82513 жыл бұрын
I have no idea what the limits are on a PT6 , but that question sounds more like the pilot is using that turbine temp as a setting to maintain a proper climb out or cruise airspeed.
@ugalas3 жыл бұрын
Thank you again for such a wonderfully informative vid. I have learned more from you then?....thank you ‘J zed’.
@ValExperimenter3 жыл бұрын
To see the effect of an extreme case of turbine over temperature look for the video "Tractor Pull Accidents - Crash Encounters", at 0:56 it starts with flame leaving the exhausts under full power, at 1:03 turbine 1 explodes at 1:04 turbine 2 explodes. I guess they were used to diesel engines, no harm in over fuelling !
@chadmiea90003 жыл бұрын
Can you give a little bit more information about the blade that gets the highest temperature and highest pressure please
@teenflon3 жыл бұрын
interesting, I imagine the blades are glowing hot when in normal operation at that temperature. Are there not composite type materials that could be used that can withstand higher temperatures? I imagine not or it would already be used!
@pey-yote3 жыл бұрын
“Air, not fire, makes the plane go higher” Happy Labor Day, Z!
@dennypollard80043 жыл бұрын
The powerplant for this aircraft in question is a PT6A-34, you were correct. Max power 700hp.
@matthanson64383 жыл бұрын
Dear Mr Z, not sure if you're taking questions anymore and you may have answered this in the past but I figured I should ask anyway as I cant find much online or on your channel. My question is about inertial separators. I know they are supposed to eject debris from the engine (??? I think ???) but I have no idea what the actual mechanism looks like. I'm also not sure if the separators are aircraft specific or engine specific. Thanks! p.s. your videos are awesome
@AgentJayZ3 жыл бұрын
Inertial particle separators are used on the intakes of some helicopter engines. They are discussed in the introductory text books I recommend in my video called "Books!"
@matthanson64383 жыл бұрын
@@AgentJayZ thanks!!!
@vaughankg3 жыл бұрын
I think the writer is referring to the vlog by Missionary Bush Pilot
@hamidsabri21883 жыл бұрын
Can u take a closer look for us and talk about the starter of those engines please
@AgentJayZ3 жыл бұрын
On my channel page use the search bar to find a few vids on starters
@TeemarkConvair3 жыл бұрын
,,,and an excellent answer
@sonaaila4993 жыл бұрын
THANK YOU AGENTJAYZ
@10fantic3 жыл бұрын
FIRE BABY🔥🔥🔥🔥
@charliemonster423 жыл бұрын
That damaged blade (at approx 15 minutes into the video) is so cool! Do you have any similar ones you'd be willing to part with? (for a fee, of course) Love the videos, they're always very informative and interesting.
@AgentJayZ3 жыл бұрын
Of course! I would love to give you something, and send it you completely free! And what would you do for me in return? Nothing? Hmmm. Let me think on that a bit.
@charliemonster423 жыл бұрын
@@AgentJayZ I didn't say free, I said for a fee...
@AgentJayZ3 жыл бұрын
OK, I'm dyslexicly projecting... again. We have some junk blades. On the channel page, you can find it.
@charliemonster423 жыл бұрын
@@AgentJayZ no worries - I'm sure you get all sorts of grifters and beggars on the page trying to get free stuff. It must be exhausting. I'll have a poke around on the channel and see if I can't find the aforementioned vidjayos.
@furkanipekoglu3 жыл бұрын
@@AgentJayZ I'd like to buy them too, it's very exciting having a burned turbine blade :D would like to carry on my backpack 😅
@kasumimello60143 жыл бұрын
Hello AgentJayZ I was wondering if you ever looked at the skylon spaceplane from reaction engines, if you have what do you think about the applications of the precooler in jet engines especially turbofans to achieve higher speed?
@AgentJayZ3 жыл бұрын
The Skylon precooler is designed for cooling the air which becomes heated during ram inlet compression when the inlet is traveling above mach 5 or so. Since even fighter jet turbofans can barely get almost to mach 2.. a precooler on their inlet would be as useful as drag chutes on a golf cart.
@terrymcdermott84123 жыл бұрын
AgentJayZ dtdtdttttttttttttttttttdtdttzztzdtdz
@lightningevo54293 жыл бұрын
I have a question. I been watching some aircraft vids and I noticed that when sitting infront of the engine you could here a sort of low tone buzzing/huming tone. Could explain what that is? I am quite curious about it.
@ivarbiermann92783 жыл бұрын
Any info on the dutch starfighter engine??v
@salihtok27813 жыл бұрын
Thanks!
@hemjoiser9363 жыл бұрын
sir which course to pursue to masters in jet propulsion??
@shainemaine12683 жыл бұрын
Does the airflow get reversed as it travels through the combustion chamber/hot section of this PT6 engine? (Looks like it in the diagram) And what are the advantages of this? (If so)
@AgentJayZ3 жыл бұрын
The gas path itself of the engine takes many turns, but the air always flows smoothly through It, from inlet to exhaust.
@KronosIV3 жыл бұрын
Is it possible to run engines hotter than originally specified if the turbine blades are ceramic-coated like the ones you've shown a few times? Or is it just used to increase the safety margin?
@AgentJayZ3 жыл бұрын
I like to think of the coatings as extra protection from thermal transients. As we have seen form our industrial engines, if you run the TBC coated blades at "stock" temperatures, they last basically forever. The user can do whatever they want, and some are interested in greater performance by running hotter. That's guesswork, with a very expensive machine...
@racingmotorsfr2383 жыл бұрын
It's possible to activate subtitle ? Thanks
@pinkdispatcher3 жыл бұрын
"Gas producer" seems unusual, I mostly hear them called "gas generator", but whatever. The Quest Kodiac is sort of a better, more modern and slightly smaller Cessna Caravan. They are easy to mix up: single turboprop, fixed gear, strut-braced high wing. And here's some pronunciation guide for the German inventor: "Hunns fonn O-hine".
Gas generator, probably refers to the hot gas produced by the engine to power the freepower turbine
@pinkdispatcher3 жыл бұрын
@@DeepCZero3, @Dino Alberini, Yes, thank you, I know what it *is*. I was referring to AgentJayZ using the unusual word "gas producer", instead of the more common "gas generator".
@khaledyousfi71603 жыл бұрын
Please, can I know the book that you're using in this video?
@AgentJayZ3 жыл бұрын
It's featured in my video about books. It's called "Books!"
@lasersimonjohnson3 жыл бұрын
Can you elaborate this.... Do we now have to pay more now to watch your content ? Or will the patreon content be posted on youtube later ?
@AgentJayZ3 жыл бұрын
The Patreon channel is a separate project, and contains material that the general audience finds boring. I'm not interested in dealing with them. The people interested in the work I do on turbine engines realize that for 5 bucks a month, they get a half dozen highly detailed videos, without any commercials. Also on KZbin, I am lucky to have a 90 to 98% like to dislike ratio. On Patreon, it is always 100%, so I must be reaching the right people. I will continue making YT vids, and continue with the Patreon effort.
@joshtargo68343 жыл бұрын
Trying to work out some energy calculations. For a J79, do you know the temperature of the air just after the last compressor stage? Pressure there is about 200psi, right?
@AgentJayZ3 жыл бұрын
For a J79 in good condition, CDP should be about 160 psi.
@joshtargo68343 жыл бұрын
@@AgentJayZ do you know the temperature of the air at compressor discharge, or do you not take measurements at that location?
@andreabraghin55263 жыл бұрын
I'm currently studying mechanical engeneering in Italy and I don't know much about jet engines (yet), but after a compression at 218psi (15bar) temperature could be around 700K (426,85 °C). These are all theoretical data from my exercises. My guess is that in reality both pressure and temperature are a bit lower due to energy losses. I hope it helps
@imagecrafting3 жыл бұрын
Always wanted to know... Why "Agent" JayZ? What is the meaning behind Agent???
@AgentJayZ3 жыл бұрын
It's a bit of a story. Subject for a video, maybe...
@imagecrafting3 жыл бұрын
@@AgentJayZ i vote for that video next!
@amascia83273 жыл бұрын
OK... jet fuel max temp around 3800°F or 2100°C... (1 bar, 68°F, 20°C initial conditions). I'm guessing modern vented ceramic coated blades & nozzles might be able to sustain half that (?¿?)... lots of development room left, eh jZ? PS: itt of 740°C is 1364°F
@gkw12323 жыл бұрын
Sir this book gives knowledge about engine
@001BIGCHIEF3 жыл бұрын
Why not do something on the most popular turbine used in the USA the Lycoming T53
@AgentJayZ3 жыл бұрын
I have not worked on one of those.
@001BIGCHIEF3 жыл бұрын
@@AgentJayZ I have two T53-703 in my boat it would have been great to see one torn down and inspected.
@rouvierredavis92163 жыл бұрын
Good day AgentJayZ. How does a pilot reduce the ITT when operating the aircraft? Does he reduce the air flow or enrich the mixture? Possible reduce power? Thank you for an interesting video.
@AgentJayZ3 жыл бұрын
Reduce ITT by reducing fuel flow. There is no way to control airflow except by changing rpm, which is a result of power level, which is a result of fuel flow.
@charlie2623 жыл бұрын
“Heat, upon heat” -Dune
@sethg45842 жыл бұрын
10 people dislike because they hot started.
@estebanferrazzi6303 жыл бұрын
Did you study engineering or all of your knowledge comes from experience? Greetings from Argentina
@Toppradd3 жыл бұрын
Esteban Ferrazzi - he’s agentJZ...he could tell ya, but then he’d have to kill ya...
@AgentJayZ3 жыл бұрын
Either one to the exclusion of the other is a faulty strategy. It's the combination that yields optimal results.
@williamgibb55573 жыл бұрын
All engines work "best" and economy wise at highest safe temp. Diesel's, gas, turbines and nuclear higher is best. Only electric which are actually motors work best at cooler temps. Of course, the human engine, well you know that answer!
@grahamj91013 жыл бұрын
It's the basic thermodynamics of a heat engine. The higher the top temperature of the cycle and the higher the pressure, the greater is the thermal efficiency.
@shoutout.kokain87133 жыл бұрын
0:51 how i look when i'm spelling my last name for someone for the fourth time lol
@greghelms44583 жыл бұрын
Your videos ought to be required watching at jet tech schools.
@AgentJayZ3 жыл бұрын
I hear from many folks... that I am...
@greghelms44583 жыл бұрын
AgentJayZ that’s awesome. After many many years of ongoing training in the car business. Computer based and hands on. I think it would have been cool to have a guru that actually does the work you’re learning to look at on a regular basis.
@mikecowen65073 жыл бұрын
@@AgentJayZ Now if they'd give proper attribution, or better yet, proper "consideration" for your hard work for a class you're effectively helping to teach "for free"...
@cg99523 жыл бұрын
It's like burning up pistons in your car.
@todddembsky83213 жыл бұрын
Sir Special Agent JayZed, In the early days of turboJets or Low Bypass Turbines, the flight crew (engineer) would turn on water injection during takeoff (The old films of B-52's doing MTI would turn the sky black with soot) Was this done to increase thrust due to greater air density with water injection, or did this allow for the burners to run a hotter burner temperature as the water would evaporate and cool the gas temp coming off the gas generator? Also, where were the water injectors placed inside the turbine? Pre Compressor, Pre Burner, Pre gas generator, Pre Power Turbine? Thank you kind sir.
@ASJC273 жыл бұрын
It was primarily to allow burning of more fuel while keeping the temperature within the turbine's limit. It had a secondary effect of slightly increasing mass flow.
@grahamj91013 жыл бұрын
If any of AgentJayZ's subscribers wish to see an ex-Concorde Olympus 593 running, then go to Adrian Bennett's Jetpower.co.uk KZbin channel. He ran the engine yesterday (Sunday) afternoon and broadcast it live.
@jurepecar90923 жыл бұрын
I guess the Kodiak pilot in question is kzbin.info . He flies to some interesting places ...
@PeterSzaboSVENSK3 жыл бұрын
Yes, he is :)
@natesmartkid64933 жыл бұрын
Me just casually putting a T58 in a motorcycle:
@pgtrots3 жыл бұрын
What is that book??
@AgentJayZ3 жыл бұрын
It's one of the books featured in my video called "Books!"
@thomasb74643 жыл бұрын
@@AgentJayZ What is a "book"?
@AgentJayZ3 жыл бұрын
It's a legacy device with instant random access, immunity to malware, zero energy usage, and infinite backwards compatibility. It is physical data storage, so the medium does have a lifespan, but can typically run error free for over a hundred years.
@chriholt3 жыл бұрын
"Kablammo" is what Juan's son said when Juan's mighty Luscombe had a "firm" landing :)
@dougbourdo25893 жыл бұрын
Going to add this (Kablammo) to my vocabulary and attempt to use it daily !!!
@AgentJayZ3 жыл бұрын
Yes, and using two m's is the correct spelling...
@JeffCowan3 жыл бұрын
Kablamo!
@furkanipekoglu3 жыл бұрын
13:23 ouch!
@furkanipekoglu3 жыл бұрын
15:02 I would like to hear that sound... On ground of course 😅
@austinallmond72113 жыл бұрын
Would graphite or carbon fiber be a potential alternative material to make turbine blades?
@alisonfox73183 жыл бұрын
no
@2ebarman3 жыл бұрын
Don't they oxidize at high temperatures in oxygen presence? Carbon likes to do that.
@AgentJayZ3 жыл бұрын
Amorphous carbon and carbon fibers are consumed by oxygen ( burned) at high temps. Slowly, but they are consumed.
@alkooj3 жыл бұрын
Think advanced nickel alloys, with advanced casting methods (more uniform grain or single crystal), with really expensive Thermal Barrier Coating formula
@2ebarman3 жыл бұрын
@@alkooj There are some form of composite blades possible I think. The engine in f-35 has turbine inlet temperature around 2000C°. If I remember correctly the turbine blades in that engine aren't made of metal.
@SuperAWaC3 жыл бұрын
i can't see a dune reference without going to watch the dune redub by sequentialpictures
@AgentJayZ3 жыл бұрын
Take your hand out of the box, young human...
@SuperAWaC3 жыл бұрын
@@AgentJayZ welcome to larrytown
@grahamj91013 жыл бұрын
May I just share this thought on the nineteenth anniversary of 9/11? A short while ago I was watching a documentary on TV here in the UK, which disputed both the official explanation of the collapse of the towers and the conspiracy theories. I was suddenly and forcibly reminded that my daughter stood on the observation deck of the south tower on 8th September 2001, before flying back to the UK the following day. Her original plan had been to have the following week in New York.
@Phoenix-ej2sh3 жыл бұрын
I *need* a J79 bookmark.
@AgentJayZ3 жыл бұрын
I got some. Trade. What you got?
@Phoenix-ej2sh3 жыл бұрын
@@AgentJayZ 16 gigs of older DDR3 1866mhz RAM, more HDMI cables than I can shake a stick at. Wish I still had some old kitschy stuff like 10base2 T connectors or something.
@furkanipekoglu3 жыл бұрын
@@Phoenix-ej2sh 😂
@greghelms44583 жыл бұрын
Crap. Still can’t get pole position.
@DeliveryMcGee3 жыл бұрын
Wasn't there a Soviet fighter jet that could do Mach 3 ... for two minutes, and then required new engines? Basically same as overheating a piston engine to the point of the head gaskets failing, but at least they'd hopefully shoot down an American bomber and maybe have enough left of the turbines to limp back to base or at least friendly territory. Fake edit (I looked it up before posting): MiG-31! Quoth Wikipedia: "was normally limited to Mach 2.83, but it could reach a maximum speed of Mach 3.2 or more with the risk of engine damage." I.e., those turbine blades aren't coming home. Also apparently the skin starts to melt around max engine RPM as well, especially at low altitudes where the air is thicker, up where there's relatively little air to compress (supersonic heating is from compressing the air, not friction), EGT was the limiting factor.
@ValExperimenter3 жыл бұрын
MIG25, it was an interceptor rather than a fighter, essentially a drag racer with wings. The engines were very low pressure ratio turbojets. In the 90's it was possible to get a flight in one of these to the edge of space, they would accelerate through the atmosphere till the air ran out and follow a ballistic trajectory out of the atmosphere.
@ASJC273 жыл бұрын
@@ValExperimenter That's an overstatement. It could do a zoom (ballistic) climb to about 200,000 ft (about 61 km) but that is still well within the atmosphere. The accepted definition of the edge of space is the Karman line at 100 km.
@ValExperimenter3 жыл бұрын
@@ASJC27 No problem I mix up feet and meters sometime I had the figure 115000 in my head. but there is certainly not enough atmosphere to run a turbojet up there.
@phrodendekia3 жыл бұрын
Ive got to send you an Argentinian flag
@cursedcliff75623 жыл бұрын
Why did you turn off the comments on the sound you never want to hear video? It was a comedy gold!
@jacobpoucher3 жыл бұрын
i agree stop censoring the people
@AgentJayZ3 жыл бұрын
reading 200 comments by people who don't understand how time works, every day is not fun. Once the traffic calms down, I will re-enable comments.
@AgentJayZ3 жыл бұрын
JP, I don't agree with you.
@percyjamesthomasdog3 жыл бұрын
Turbine boy
@michaelhill95553 жыл бұрын
Hmmmm, my ex-wife also used to refer to me as a "generic gas producer"
@jackmehoff15653 жыл бұрын
So basically if you want to see the good stuff you have to pay will what if I can’t afford to pay because I have kids to feed I was a faithful sub but not no more
@AgentJayZ3 жыл бұрын
Your KZbin subscription is unaffected. The KZbin content will always be free to enjoy by everybody. You can always choose to cancel your free subscription, if you want.