A line up of eight combustor liners from five different manufacturers allows us to compare the similarities and differences in the design of this critical but often overlooked component of gas turbine engines.
AgentJayZ - I've got to say, your videos are a geek's paradise. I greatly enjoy your tours through turbine engine parts, start-ups, running, afterburning snow-clearing, etc. Thanks for taking the time to post super-interesting and informative videos.
Hi, it is my believe all of us, fans or workers in the aviation, power plants entusiasts, need to thank you for your great work. You are transfering to all of us, what you love to do. Today we learned more of a very special part of these engines, the combustion liners. I remember wrote about the annular liners, and they are quite expensive units. These liners are used in the commercial airplanes and more fuel efficient than cans. Thank you again and keep doing this great work.
Thank you for the clarification. There aren't very many ways a non-expert like myself can get a look into the inner workings of these engines. It's very nice of you to share your experience.
I just discovered your channel and am finding this stuff fascinating. I'm a teacher. You're a great teacher! I'm amazed that people can figure these designs out and have such confidence in them! I'm also amazed with how "simple" the basic design is. Your description of the burners reminds me a little of the burners on a gas stove with an ignitor in just one spot. Thanks!
It is amazing that much of this technology was advanced long before computers were able to calculate CFD. Trial and error wasn’t an efficient way to create these assemblies, but the results of manual engineering was astonishing, producing great engines long before computers helped fine-tune these to be more powerful and efficient.
A very interesting report on the development of various combustion chambers. - Can - Combustors, tube - annular combustors and finally annular combustion chamber as in history. I have never in my life seen before these parts so close and well explained. Thank you :)
Great look at all the various components of different engines. This sort of stuff is few and far between on youtube, so thank you very much for taking the time to record and explain the various functions of each part in easy to understand terms. Great to get an insight into the innards of these engines.
I want to say thank you as well. I started learning about Jet engines not long ago. I spent a few hours watching one animation of a Turbo Jet engine until I finally wrapped my head around the way it worked and ever since I have been almost obsessed. It was very nice to see actual internals instead of just animations, they had actually had me puzzled for a long time about how such a thing would be mass produced. My biggest puzzling thought I seen you tried to explain was how to design the best possible designs for parts like the combustion chamber. I found the Pratt And Whitney the most interesting, I liked the way that it would make the fuel air mixture create a swirling motion before it moved onto the next cycle like normal piston combustion engines try to do with their intakes.
Thank you for the video. I've been fascinated by gas turbines for years and have just begun the deep dive into understanding their theories of operation. The video has been very helpful for a beginner like me!
We weld repair them using stainless steel. The better the design of a combustor liner, the cooler it runs. In modern engines, they are ceramic coated. I'm not sure what the underlying metal structure is made of. Possibly Inconel, but it may very well be stainless steel.
I work in a technical field and have to know how energy moves around. I take pride in my knowledge and ability. You, sir, blew my doors off with this video. I can surmise what's going on with the engine and fuel air mixture based on your explanation alone. The pure Tonka Toy geekiness of this warms the cockles of my heart, though. Thanks for posting.
This is another well explanation of combustor liners. Once I talked to you about annular combustor liners, but you don't work those, they are for commecial aviation. Thanks for this video and all the other ones. You are a good teacher!
We work on large industrial engines, occasionally military flight engines, and very rarely special projects like land speed cars, race boats and UFOs. Never mind that last one. The PT6 is a civil aviation engine, and we are prevented by law from working on anything in civil aviation. There IS an industrial version, called the ST6, but it is rare, and we have never seen one. Maybe someday...
Built combustors baskets for gas turbines at Westinghouse in the 80's! The Westinghouse 501 was an awesome engine to work on! We basically used Hasteloy, and had to punch out the holes and spotweld the rings together! Metal was too hard to drill!!
I tell you right in the video, at the same time you see it, that it's from a JFS100. It's a small gas turbine starter used by several US military engines.
Great overlook of the different designs. The inner combustor liner of JFS-100 looks preatty simmilar to the ones we use in our small gas turbines (ring of fire :-)). I`d love to have one of those old J-79 combustor liners - they look so cool. Really interseting video - thx for showing.
It is there to swirl the small amount of air that comes through the snout and is used for initial combustion of the fuel. It is swirled to both decrease its axial velocity and to promote better mixing with the spray of fuel coming out of the fuel nozzle. This is a general description. Keep in mind that combustor liners are designed by a mixture of trial and error, black magic, and a tiny pinch of aerodynamic theory.
Amazing site, I work for Rolls-Royce and used to make the anular comdustors for the Panavia Tornado, the RB199 turbojet, I was the main Quality inspector. In now make the large fan blades for all the Trent series engines, very big fan blades
The T56/501 uses a set of can-type liners inside a common outer case. This is known as the can-annular, or cannular arrangement. The can-type arrangement is what you see on our Orenda type 14 or J47 engines. These inaccuracies, presented in an instructional manner, are forcing me to remove your comments, as they are misleading to people who may not already know and are trying to learn.
@TheMan1510 A cmbination of stainless steel for toughness and resistance to cracking, and refractory alloys like Inconel or Hastelloy for maintaining strength at very high temperatures. They live in an environment of 1000mph wind at a temp of roughly 1000F, so they are built to be as far from fragile as possible.
Thanks. Good study material for pilots and I always love seeing animals in the shops. They are cute, funny and provide much needed comic relief. Studying does get stressful every once in a while!
Hey just wanted to let you know your vids are awesome im a marine just started in my unit as a mech on hueys there a bit different than these turbine engines but im tryin to learn anyway i can and your vids r really helpful so thanks and i hope u will keep doing them
@MoowChair The pressure difference between the outside of the combustor liner and the inside is very small; just enough for the air to flow inwards through all those holes. The main stress on the liner is heat radiated from the flame of the burning fuel.
@mytmousemalibu Yes, the turbine inlet nozzles direct hot combustion gases at the turbine. Whatever it is that makes those gases it not something the nozzles worry about.
@egn83b I don't know what makes a sterling engine work, but I think it works on the Sterling cycle... ? A piston engine works on the Otto cycle, and a gas turbine works on the Brayton cycle. These things, descriptions of, of me, ask you not... of you , in advance, thank, do I.
I'm just a guy who works with the stuff, and is interested in the history of how it all came to be the way it is... Lucky enough to get to tear apart and put together his boyhood dream... Jet engines and Rocket ships ! Ok... got a bit carried away there...
absolutely awesome, thank you for patiently showing us, explaining in just enough detail to understand it but not so much detail that it's boring, monotonous and we wish I'll upon you and shop kitty.
like the video. reminds me of when I was in high school we had an aircraft maintenance shop class. makes me wish I stayed the course and went to a tech school.
Yeah, that impressed me too. The most expensive stuff is that which runs hottest. and is subject to the highest force, ie, centripetal. So that means the turbine blades, and the mounting ring they sit on, followed by the stationary stator blades. They (engines) do actually last well, and I wouldn't call the maintenance minor or simple, but turbine engines have become a bit of a miracle of reliability, in view of the temperatures and forces, they don't fail very much. Exceptional engineering.
I have a Rolls Royce Derwent combustor liner. I was looking up info on it and found a really good PDF of an old Rolls Royce book called "Rolls Royce the Jet Engine Fifth Edition" that has some pretty interesting info on the configurations of the different holes on their liners. For curious folks, like myself, it's worth checking out for sure.
I don't call them injectors, because they contain no valve or other method of controlling fuel flow. They are not called combustion chambers, because the space where fuel is burned is made up of two separate parts: the outer case and the liner. There are different types of liners, so the question of how many ignitors per liner has several answers: either one, two, or none...
Thanks for taking the time to show this stuff, it's fun to see. What did you study, and for how long? What is your role at that shop? What kind of metal are those made of and why? Some of those designs are very aesthetic, especially the one with 6 mixers. Others have some resemblance to the Dyson blade-less fan. Thanks!
They are not fuel injectors, because they have no valve or any way of controlling the amount of fuel flow. They are called nozzles because that's what they are. Interestingly, fuel flow is controlled by a device called the fuel control. I do have a few videos posted featuring fuel nozzles in action being tested.
@matube73 It's all the same airflow coming from compressor. As you can see in video, only small part of it "is burned", larger part is squeesed through combuster liners later, which cools the exhaust gases, but all air comes from compressor. If I'm wrong, blame JayZ :D
The Orenda looks like a lawn ornament, the Rolls Royce like it has been spot welded from scrap by a bored employee, the General Electric stuff looks functional....And the Pratt and Whitney unit is so bling that it looks like a rap artist has designed it.
@milesall1 Out in the open like that, the holes in the liner would allow air to flow out, when in an engine air flows from the outside of the liner inwards. Your demo would be ultra cool if we could somehow make a combustor case out of glass so we could see inside a real running engine... Hmmmm....
hello agent zay. i want you to deeply explain the combustion part---you have explained about the combustion liner but the outer part or the outer case isnt explained. awsum video
Thank you very much !!!! I never seen a real combustor in my life and probably never will... And had no idea what they look like, now, i know. 1/2 million $ for the annular combustor.... Me too, i'd let it lie on the ground...
Cool videos !!!I am very impressed with them all.My job is closely related. I work at a laser shop, and we laser a lot of parts for the aerospace industry. I happened to notice one sitting on top shelf behind you at the beginning of this video and was wondering if you could show us where in the engine it goes.We call it an M08 and burn all the holes and tabs at the top of the part. Thank you keep up the awesome videos!!
Another great vid Jay. Excellent close ups. Question please:- What feeds all of them mixing holes to cool the burnt gases in the combusters? Is it from airflow around then engine? How does this work in a fighter jet set up? Cheers.
Any footage of reverse flow annular liners? I work on PT6As and I rarely get to see internals upstream of the power section. ....well, without using a boroscope that is.
it seems in your video's watching and listening gives me the answers I seek thankyou the burner cans from the Orenda turbo-jet are larger than the J47 are these more powerful or are they bigger for greater cooling air around the inner cans this engine has really grown on me, I will try to find a small model to go with my RR Nene model but do want the Orenda and not a J47, thanks again AgentJayZ
Thank you for sharing the information with us. The flame can reach up to 1700 Celsius, i guess u already know about that. but I didn't know that the guide vanes can reached around 1100 degrees. I know it's HOT but I don't have the figure. Thanks
I really enjoyed this evolution-peice! Would it be possible to make more of them? like from J47 (or earlier) to the present on various parts? I get that this was a rare opportunity, perhaps acquiring the footage of various parts over time could be a solution to that?
Any Idea how those are welded together? I tried to modify one several years ago and it cracked at every weld. I was welding with inconel wire using argon shielding gas. This was for a test project at one of our universities so I dont know which model it was. Charles
Hi AgentJayZ many thanks for the informative videos. I have known liners are being used in annular type combustion chambers to protect main material from high temperature. However I see no liners in this can type combustors. How are they protected from high temperature? Are they replaced frequently?
I was just wondering the area where the igniter is put for a commercial engine combustor, in replacement of the igniter is instead an oxygen acetylene torch. You light it with one of those strikers like in chemistry and the. Set it to the blue flame. Would it combust what was needed to start the engine
@86Ivar I think both, and they aren't made in large numbers, so economies of scale are not achieved. And I'll bet the tooling to make them is phenomenally expensive. Sure, it looks like a few rings made of thick sheet metal, scrunched into wavy patterns, welded together, drilled for ventilation, and then coated with ceramics.... but it all has to be dimensionally correct to within a few thousandths of an inch in every direction... that's "perfect" to us mere mortals...
What does the flame look like, how far does it propagate from the low pressure area in the liner? Are any of these used combustors able to be placed placed back into service? What are the liners made of? stainless?
@@AgentJayZ lol no thanks, xD I'll buy a pair of engines if you can do $800 a month, for 25,000 months. They would be payed off by the year 4100 or so. I'll gladly pay Tuesday for a turbine engine today.
Nice video! Do you know if the annular 500000 buck combustion liner is so expensive due to an advanced production process, or for all the testing and development?