Afterburner Liner Shapes 

I am so lucky to work where I do... I feel it's my obligation to share it !

You are correct Like corrigated iron for roofing and others

Gutters ‘machined’, really?

Hi John. The basic shapes were pressed whilst glowing hot. Then little square holes were machined for the mounting brackets which were TIG welded in. The brackets were then slotted using a triple gang mill to fine tolerance. I used to do this last op.

Send a hat, and I'll wear it and mention your institution in a video.

The Buccaneer is the loudest plane I ever heard.

@@givenfirstnamefamilyfirstn3935, you haven’t heard many, have you, if that’s the loudest you’ve heard? Loudest I have heard was earlier this year, at RIAT, when the F35 was in the hover.

@@johnnunn8688 Have you heard a Buccaneer close at low level then? It had/has no jet pipes or afterburners/reheat, the exhaust is straight into the exterior air and is exceptionally loud even though it has low bypass turbofans.

I don't know of any test we've done where I wasn't shocked by the noise level. LM1500, LM2500, J79, J47, Orenda 10, Orenda 14, RR Avon, RR Spey, RR Olympus, Wright J65, and even the RR Tyne when it gets "on the pipe". It's all roaring thunder...

@@givenfirstnamefamilyfirstn3935 , the Phantom Spey has reheat added to the noise. Trust me, the Phantom Spey is louder, much louder. The F35 is louder than that, by an order of magnitude.

Their purpose is the subject of this video.

Oh, it's an old timey thing. Sort of interpreted as "darn it" or "aw, shucks". So, you knew it all along. It was probably a new thing to our grand parents.

The afterburner doesn't generate separate thrust, it just boosts the velocity of the exhaust gas already coming out the back. (Not a jet engine mechanic, so there may be some fine detail I missed, but that's my understanding) Quoth wikipedia: "The afterburner increases thrust primarily by accelerating the exhaust gas to a higher velocity." it's backed up by footnote 6 on the "afterburner" page, if you want to see the math.

Thrust is generated by the acceleration of exhaust gases as they pass through the final nozzle. So you could say the reaction forces act on everything ahead of the nozzle, which is every part of the engine.

The thrust would act on the entire engine. Thrust goes one way engine goes the other.

That is a FUN QUESTION with probably a proper complex answer that might need an engine designer to explain it in detail. The engine designer from RR did touch on some aspects of this and Jay does talk about it also.

I have a video called "where does thrust act?" and a search feature on my channel page.

The terminology might change, but I think all modern afterburners work this way. The J-79s we work on have two separate manifolds for carrying fuel to the spraybars on the early models, and four on the later models. Each spraybar has four sectors, each supplied by one of the manifolds. Each manifold is supplied by the AB fuel pump through a valve that opens at a specific pressure, increasing from the first to the last. The afterburner is progressive, but the fuel pressure to each little orifice in the spraybars is maintained above a minimum, so no dribbling occurs... Here's a vid i made about sprabars ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-IHVnWVgzUE8.html Actual fun fact: the manual states that in order to bench test the afterburner fuel pump, an electric motor of at least 175 Hp is required to drive it.

@@AgentJayZ That is a mighty powerful electric motor, man, oh-man.

Yeah... we test the AB fuel pump by hitting full AB in an engine test. It's impressive, as you can see in many of my vids.

I think that's the exhaust duct that they use when testing power turbines.

It's the exhaust duct we use for the Tyne. It has an integral power turbine, so doug is very close to being correct.

@@AgentJayZ So to clarify, it's because of the power shaft extending out the rear of the gas duct that the exhaust flow is turned 90° and thus requires an "exhaust pipe".

We have heavily modified a Solar Saturn exhaust manifold for this purpose. I honestly have never seen a real Tyne exhaust duct, either for aircraft or for the marine version...

@@AgentJayZ Yes! That inverted teardrop/banjo shape is exactly what I visualized. Thanks!

The fast moving air is inside the jet pipe. The cooling air is at a slightly higher pressure.

@@AgentJayZ Thanks for info, I’m just a layman but I was just wondering if those slots were used to create a Venturi effect from the fast moving jet air in the center of the engine? Great videos…

They are filled with sillica gel to absorb humidity. Usually they are lots of them when the engine is in its crate.

That's dessicant. It dries the air in a sealed container. A container for the Iroquois would need about 50 of those bags. Those two are just litter.

Each bag is based on units, depending on the size of the bag. We still preserve the T56 with 28 bags using tech "Manual to the SPI standards. "method 50". You can reuse those bags by microwaving them, but we've never done that. We just buy new 100%

It's much safer to renew the dessicant by heating in a standard oven to 275F for 24 hours...

Turbine case temperature at idle will be over 700F, and close to double that at full power. Never thought of sitting there.

@@AgentJayZ Some insulation in between and you'll be right.

@@AgentJayZ Do you ever choke the intake of a turbine (compressor) to simulate a high altitude environment, or is it just a sea level static test?

When you put (compressor) right next to turbine, that's usually a way of indicating the two words mean the same thing. Nothing could be further from the truth. In function the two are exactly the opposite. I have a vid called what makes a turbine turn, which will help you, I think.

@@AgentJayZ I think he's just using the word turbine to mean "jet engine" then specifying compressor?

You might want to watch my vid called Power Turbines and What They Do.

I try to discourage any descent into politics.

@@AgentJayZ You're right, it is jet channel.

They had a service life, its not like you can use it at home. If they are going to waste alot of the money anyway might as well make advanced jets what if we need them and we dont have them.

For perspective, the price paid by the government for a J79 in the late sixties was about 100K US. How many of those could you buy for one F 135?

@@AgentJayZ I dare say one "might" be able to buy "all of them"? But that's a wild guess.

@@AgentJayZ Yeah, the numbers I've seen were $625k US in 1960 each for a J79, which is about $6.5M today.

Well, it's one of the most successful turbine engines ever made. I think the total number produced is just over 18 thousand. One of the reasons we will never run out of parts for it in our lifetime.