Kaveri & Aero-Engine: News & Discussion

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fanne
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Re: Kaveri & Aero-Engine: News & Discussion

Post by fanne »

Suddenly for the past 2 days at least 10 defense Youtube channels are blabbering about Kaveri. I heard all of them, but what they are saying makes no sense. Is it kite flying? pure speculation?

They are asserting these things -
1. DRDO is getting its own flying test bed (not seen any news from any credible source in the last 1 week)
2. Some breakthroughs in Kaveri itself (the discussion is often intangible - it is better, good , more this and that)

Any ideas? Or just everyone is chasing everybody's else tail?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by NRao »

fanne wrote:Suddenly for the past 2 days at least 10 defense Youtube channels are blabbering about Kaveri. I heard all of them, but what they are saying makes no sense. Is it kite flying? pure speculation?

They are asserting these things -
1. DRDO is getting its own flying test bed (not seen any news from any credible source in the last 1 week)
2. Some breakthroughs in Kaveri itself (the discussion is often intangible - it is better, good , more this and that)

Any ideas? Or just everyone is chasing everybody's else tail?
Neither one should be a surprise.

With so many AI planes to spare (from what I have heard), the first one is a distinct possibility.

And, given the time that has passed, I would not be surprised that multiple individuals/groups have been trying (and failing) often enough to find that needle. About time - of course the assumption is that someone has been at it all these days. (And, IMO the only way to get "an engine" - try/fail until you succeed.)


My glee would be more about the birth of the try/fail cycle culture, than the one solution found for the engine.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by fanne »

I hope so, but otherwise no definitive news one way or the other.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ramana »

News report:
https://www.theigmp.org/2022/06/new-76- ... kw-Tw4&m=1

Basically new turbofan with reheat for AURA.

Plan for 50-hour Aircraft tests in Russia.
Delayed as usual.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

$20 billion (at minimum) for 114 MRFA, but GOI will not invest in a couple of used B747s or A340s to serve as flying test beds.

Our priorities. Wow! :roll:

HAL is scouring the globe for six used B767s to be retrofitted as in-flight refuelers.

The wild conspiracy theorist in me believes that someone (or perhaps more than one) in the GoI and/or the IAS is covertly killing India's efforts to develop a viable low bypass turbofan. That is the last technological hurdle for India to overcome. It will be our "we-have-arrived" moment. Within our grasp, but there is always an issue with funding. Some excuse is always given.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by karan_mc »

ramana wrote:News report:
https://www.theigmp.org/2022/06/new-76- ... kw-Tw4&m=1

Basically new turbofan with reheat for AURA.

Plan for 50-hour Aircraft tests in Russia.
Delayed as usual.
Some gibberish of report prepared on article first i saw on idrw . author almost confused himself with proposed 76kN Dry engine will be based on 110kN with AF and with Kaveri Dry engine 46kN that will suit FUFA/Ghatak
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Re: Kaveri & Aero-Engine: News & Discussion

Post by sanjaykumar »

FUFA or FLUFA.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ashishvikas »

Why likely €1 bn French deal is a reminder of India’s failure to build indigenous jet engine

SNEHESH ALEX PHILIP
9 June, 2022


https://theprint.in/defence/why-likely- ... ne/988571/
Later this month, Defence Minister Rajnath Singh is slated to review one of India’s most strategically important projects — the development of a 120-kN (kilo Newton) engine to power the country’s futuristic 6.5-generation Advanced Medium Combat Aircraft (AMCA).
French engine giant Safran is asking for more than €1 billion to transfer the technology needed to make the engines, as part of Rafale offsets contracts.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Aditya_V »

Did we get any TOT from Euro 4 Billion Scorpène construction? Rather do Su-30 type engine building and assembly in India, spend on the wind tunnels and get Flying Test Bed.

Only in India we expect a domestic solution the first time to be cheaper than the imported system, whereas given land acquisition and one time CAPEX costs and addition to economy Rupee depreciation, imported systems should be cheaper by a factor of 3. But then a lot of Babus and Ecosystem children Foreign Education/Settlement and Commission will be affected.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ramana »

Rules require 25% offset.
In case of Rafale it's 50%.
So price of offsets already built in.
If India doesn't demand ToT that's free money.
So what's difficult here to understand?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Pratyush »

ramana wrote:Rules require 25% offset.
In case of Rafale it's 50%.
So price of offsets already built in.
If India doesn't demand ToT that's free money.
So what's difficult here to understand?
1) Do Indians and the French have the same understanding of TOT?

2) Why would any vendor help making India self sufficient. Don't they want to sell again to India 20 years from now?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by kit »

Pratyush wrote:
ramana wrote:Rules require 25% offset.
In case of Rafale it's 50%.
So price of offsets already built in.
If India doesn't demand ToT that's free money.
So what's difficult here to understand?
1) Do Indians and the French have the same understanding of TOT?

2) Why would any vendor help making India self sufficient. Don't they want to sell again to India 20 years from now?
because technology is a moving on., the bleeding edge being several generations ahead. there will still be a requirement for new tech. so did the tot for the RD and saturns help india ?

I fear the 1 B is a lost cause but because it IS a part of offsets nothing lost , India needs to plough in another B into its own home engine project , a Tejas of aeroengine., an ecosystem of engines. There is no alternative to this.

The TOT for engine via Snecma would not be a solution. , but rather a band aid for the time being
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Re: Kaveri & Aero-Engine: News & Discussion

Post by A Deshmukh »

We should also get a Kaveri version for UCAV.
UCAV itself can be designed around Kaveri.
Even if a few crashes do happen during testing, it would still be a cheaper and faster way to evolve Kaveri.
Once the TD matures, UCAV can be enhanced to carry payloads.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

DRDO is doing that exact thing. That is what swift will lead up to.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Pratyush »

A Deshmukh wrote:We should also get a Kaveri version for UCAV.
UCAV itself can be designed around Kaveri.
Even if a few crashes do happen during testing, it would still be a cheaper and faster way to evolve Kaveri.
Once the TD matures, UCAV can be enhanced to carry payloads.
One crash and the project will be cancelled in favour of imported product.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

https://twitter.com/FighterPiloting/sta ... tiTV42KcFA ---> Hindustan Jet Engine HJE-2500 was made in 1965 for upgraded Kiran aircraft. The project was shelved on behest of RR, which modified Gnat's Orpheus-70101 engine for Kiran Mk 2. We should have simply continued on indigenous path rather than getting sold out repeatedly.

Image

Image
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Re: Kaveri & Aero-Engine: News & Discussion

Post by fanne »

Prasad wrote:DRDO is doing that exact thing. That is what swift will lead up to.
prasad is the plan to test the Kaveri on swift or put in swift once Kaveri has been sufficiently qualified? TIA
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Re: Kaveri & Aero-Engine: News & Discussion

Post by A Deshmukh »

Prasad wrote:DRDO is doing that exact thing. That is what swift will lead up to.
I think SWIFT is a serious TD by itself.
What I want to suggest is create a UAV/RPV just to test and evolve Kaveri.
Just take Kaveri in the air to test its performance. (ignore the other fancy stuff like stealth, missiles, radar, etc).
We can do 1000s of hours of testing, without being dependent on Russian multi-engine test aircrafts.
A remotely piloted Tejas body with Kaveri engine comes in mind.
I think this is a faster way to develop Kaveri engine and its variants.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

fanne wrote:
Prasad wrote:DRDO is doing that exact thing. That is what swift will lead up to.
prasad is the plan to test the Kaveri on swift or put in swift once Kaveri has been sufficiently qualified? TIA
swift is a scaled demonstrator to learn technologies and uses a smaller engine. Kaveri will need to be flight tested properly on a ftb but we aren't hearing anything about it other than taking it to Gromov.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by fanne »

Where there is a will there a way !! Short of proper FTB (a wide-body, multi-engine, where OEM has agreed to modify the aircraft per DRDO request aircraft) one can use these measures -
1. A proven UAV to install non-afterburner kaveri, or kabini or full Afterburner engine. The UAV can be swift or anything.
Benefit, does not run the danger of human loss, don't announce test or engine failure (unless the plane falls in habitat area, one can always test in desert or over ocean)
2. Use any other bombers we have - Canberra (if we can support it), or even Jags or Mig 29. Can we use one of the pylons appropriately rated? Is it even possible or only the engine bay can take an engine. STill second engine can be Kaveri. We may be short on Mig 29 but we have plenty of Jags. Jags have to be modified to carry the bigger kaveri, but we make it from raw material stage, HAL should be able to do it. Maybe make Jag unmanned and then risk it.
3. I wish we modify one of the wide body planes. OEM though may not want to do it and I don't know if we have capability. If yes a second hand plane can be converted.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

Kaveri is for an LCA Class aircraft. We don't have a similar jet-powered UAV to try it out.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by bharathp »

1. A proven UAV to install non-afterburner kaveri, or kabini or full Afterburner engine. The UAV can be swift or anything.
Benefit, does not run the danger of human loss, don't announce test or engine failure (unless the plane falls in habitat area, one can always test in desert or over ocean)
-- this may be a difficult proposition. if the UAV falls into the ocean or desert, it may not be salvageable - not something we can afford with the limited number of cores built?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by fanne »

This is of course not a risk-free alternative (every strategy has some good and bad). The other one is to wait for a wide-body aircraft or test in Russia - and we know where it has taken us. The other alternative of buying engine tech will require us to have this, maybe we can ask OEM to modify a few planes as FTB.
If none of the above work, we may have to go our own way and at that stage, modifying a proven UAV may be the best option. If we are sure of auto-landing and take-off flight control, a robust sat com (that communicates all engine and flight parameters continuously, to the microsecond before anything bad happens), is the way to go. Proof the engine to the extent it can be proven on the ground, then stick it on the plane and fly it. Few unmanned planes crashing is no big deal, Rustom has crashed, and it is not even in the BRF threads of crashes. If the engine was that bad, FTB would have crashed as well (or maybe not). But waiting for FTB forever and wishing it will not get us there. I am assuming that it is not money but the reluctance of foreign power to help us and our inability to modify a plane as such. US went back on promised high-altitude engine TBF as part of P8i or some deal.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

Recent Indian Developments in Thermal Barrier Coatings For Jet Engines
https://delhidefencereview.com/2022/06/ ... t-engines/
26 June 2022
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

The only plausible reason for this turnaround is the JV between Safran & GTRE is quite likely being closed to be inked. Also the fact that the 114 MRFA deal is likely going to go to Dassault and that has got the Amreekis worried. A possible loss in the MRFA contract - will be third in a row - would be humiliating to Amreeka's H&D.

US Revives Offer To Co-Develop AMCA Fighter Jet Engine With India
https://www.businessworld.in/article/US ... 22-434262/
27 June 2022
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Neela »

Rakesh wrote:Recent Indian Developments in Thermal Barrier Coatings For Jet Engines
https://delhidefencereview.com/2022/06/ ... t-engines/
26 June 2022
The article looks like paper that is published in Material engg journal .
TeT of 1200 C (1473K) seems to be achievable with LZ coating. This is still 500K away from current generation F135 PW engines it seems
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Re: Kaveri & Aero-Engine: News & Discussion

Post by maitya »

Neela wrote:
Rakesh wrote:Recent Indian Developments in Thermal Barrier Coatings For Jet Engines
https://delhidefencereview.com/2022/06/ ... t-engines/
26 June 2022
The article looks like paper that is published in Material engg journal .
TeT of 1200 C (1473K) seems to be achievable with LZ coating. This is still 500K away from current generation F135 PW engines it seems
No no, Neelaji, doesn't work that way ...

Please refer to my post, from way back in 2019, regarding this ... quoting some relevant excerpts from it:
...
...
<snip>
The issue with 7-8YSZ based top-coat TBC applications is that YSZ allows for maximum surface temperature capability of about 1200 deg C - beyond that degradation of the coating (in form of reduced strain tolerance and a decrease in thermal fatigue life of the coating) takes place due to changes in microstructure.
So, in most turbofan HPT applications the make-or-break technological aspect is film/convectional cooling effectiveness
i.e. for a Kabini/Kaveri example, the blade-surface film cooling technology, has to be effective enough to bring down the blade-TBC surface temperature from TET levels of 1455deg C to ~1200deg C. So that TBC can further ensure the substrate-metal-blades are operating at about 1050-1100 deg C levels.
This 1050-1100 deg C temp levels are firmly within DS casted blade regime - the SC casted blades can add another 100-150deg C to it, but the applied TBC simply wouldn't support any more temp creep (due to 1200 deg C max phase stability boundary limits).
<snip>
...
...
<snip>
However, recently we have seen reports of Indian Rare Earths Limited developing bi-layer TBC technology of Lanthanum Zirconate (LZ) over Yttrium Stabilized Zirconia (YSZ).

Now referring to my previous post (on this thread) pls note,
1) Lanthanum Zirconate (LZ), has much higher thermal and phase stability - close to 2000deg C. It also has lower thermal conductivity and sintering tendency compared to YSZ.
(Thermal Conductivity - 2 W/m/K of YSZ vs 1.56 W/m/K of LZ)
2) LZ is also less oxygen transparent than YSZ, providing better bond coat oxidation resistance and minimises the growth of TGO (Thermally Grown Oxide layer) - Wiki has good details about TGO and it's impact on TBC.

But the disadvantage of course is LZ has lower coefficient of thermal expansion compared to YSZ - so it cannot be applied directly on the NiCrAlY bond coat.
So, the solution is therefore to have LZ applied as a top coat material over YSZ forming a bilayer TBC.


Now suddenly, with this technology, the issue of 1200deg C limit of TBC is gone - so we don't really need the blade-surface film-cooling tech to be able to bring down the ambient/operating temp to 1200 deg C etc. As this bilayer (LZ-YSZ) TBC will happily work upto a much higher temp (theoretically upto 2000 deg C).
So now suddenly, as a chain reaction, the SC casting tech is attractive again - now we can get those additional 100-150deg C TeT levels without worrying about TBC spalding and other issues. Yes, the temp for the substrate-blades are going to be higher, but that's exactly why SC casting is being attempted for.

Pls further note, DRDO has already assembled and validated the bi-layer YSZ-LZ coated flaps in an aero-engine for test cases involving rapid thermal transients, supersonic flow of combustion products, vibratory loads of about 4 ‘g’, sustained 1,000 h equivalent of engine operation and more than 30,000 nozzle actuations.
And I'm sure testing on rotor blades of the HPT also is going on and news will surface in due course.
<snip>
...
...
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Re: Kaveri & Aero-Engine: News & Discussion

Post by maitya »

Rakesh wrote:Recent Indian Developments in Thermal Barrier Coatings For Jet Engines
https://delhidefencereview.com/2022/06/ ... t-engines/
26 June 2022
Rakeshji, this is a highly technical paper (must be an excerpt from an Journal etc), need good background of Mat Tech to fully grasp it.

However, a read of one of my very old post (from 2019), should provide a good summary of what is being talked about here - in lay-man terms of course.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Neela »

maitya wrote:
Neela wrote:
The article looks like paper that is published in Material engg journal .
TeT of 1200 C (1473K) seems to be achievable with LZ coating. This is still 500K away from current generation F135 PW engines it seems
No no, Neelaji, doesn't work that way ...

Please refer to my post, from way back in 2019, regarding this ... quoting some relevant excerpts from it:
Maitya-ji,
My poor brain is trying to make sense of your posts . Please allow me to abstract your deep technical posts to get a sense of satisfaction of understanding the gist . Have read all the linked posts as well

If I understood you correctly, Kaveri/Kabini (using DS blades) with LZ <=YSZ<=bond coat<= substrate allows for 1455 C TeT degree operation (LS and YSZ take the *heat* and substrate runs coolly at 1050C ) :wink: . Correct?

And I think what you are saying is that the same LZ...YSZ recipe can be used on SC we can add another 100-150C of TeT and the SC will happily comply?

Is my understanding correct?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

Obviously a lot of detail couldn't be published. We don't have the latest on this and blade related research was only proposed back then.

Besides, cooling is a major focus and was seen as the way to achieve higher TeT. We might actually see both methods combined (if that actually helps).
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

Prasad, I am truly in awe of the excellent work you, Saurav Jha and others do at DDR. Really exceptional.

Neela-ji, I am not an engine expert by any imagination. I read the article and was hoping maitya-ji would shed some light.

I will be reading through the link that maitya-ji sent, because that in that way I will understand the DDR article.

Thank you maitya-ji.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by maitya »

Neela wrote: If I understood you correctly, Kaveri/Kabini (using DS blades) with LZ <=YSZ<=bond coat<= substrate allows for 1455 C TeT degree operation (LS and YSZ take the *heat* and substrate runs coolly at 1050C ) :wink: . Correct?

And I think what you are saying is that the same LZ...YSZ recipe can be used on SC we can add another 100-150C of TeT and the SC will happily comply?

Is my understanding correct?
No no ... LZ bilayer TBC was (and still is) R&D domain, not used yet on Kabini etc, as far as I know.
(actually, it has been used somewhere else - later part of my post will talk about it)

To use "traditional" TBC (so basically YSZ<=Bond Coat on Substrate stuff), the ambient Temp must be <1200 deg C ... but TET of Kaveri/Kabini is 1455 deg C - so what gives?

But before proceeding any further, do note a myth: TeT == ambient temp "experienced" by HPT blade tips.
It is not, and ambient temp of HPT blade tips are actually lower than TeT - if any component of a Turbofan core "experiences" TeT first-hand, it's the static HPT vanes and not blades - and the ot gases are cooled down a bit before they reach anywehre near the HPT blades etc etc etc.
But I digress (again!!!) ... :roll:

The 1455deg hot gas (from the combustor) is first cooled down by the convectional cooling air surrounding the blades. This air is let out by numerous pores (very very very very carefully designed and laser-drilled) at various points of the blade surface.
This is an uber-niche technology in itself, only a ultra-small number of engine manufacturers possess it, and nobody (in their right mind) will ever part with that tech.
If anybody is hell-bent on believing the "bhaichara" talk by random politicians and baboons, so be it, I guess ... these stuff can't be cured!!

But I've digressed again, but since already done, so let me add just one more point (a question) to it:
viz. being a product of an global turbofan producing powerhouse, why on earth would the TeT of the mighty AL-31F be limited to 1300deg C etc, while a pure-SDRE Kabini manages 1455deg C? Hain jee, please think thru ...


Anyway, back to topic - now that the hot gases are sufficiently cooled down to 1200deg C etc, a standard TBC of YSZ<=bond coat<= substrate can take over and reduce the temp "experienced" by the blade-body by further 150deg C or thereabouts - sweet territory of 1050deg C for DS casted blades.
But, similarly, if there were no convectional cooling happening, then TeT figures needs to be reduced to a level where-in the TBC itslef can survive (further cooling in combustor itself, there goes the Thermal efficiency, so higher SFC etc) - aka any YSZ<=bond coat<= substrate TBC doesn't experience anything more than 1200 deg C ambient temp.

But but, there's a catch ofcourse ...
A 4th Gen SCB will easily allow another 150 (200 deg is pushing) deg C over a DS casted one - but it's practically useless as the traditional YSZ<=bond coat<= substrate will not allow these additional degrees in TeT.
So the option there is to improve the TBC themselves - one small/incremental improvement can be, to reduce the TBC particle size and minimise the radiation-heat-component etc, so that you can push that 1200deg C envelope to a little bit higher value.

Other option, of course, is game-changing aspects like using LZ based TBC which gives a theoretical limit of 2000deg C ambient temp.
But the issue there is, and in layman's term, LZ coats doesn't "stick" well on the traditional bond-coats. So bilayer TBC concept is used wherein LZ is applied on YSZ which in turn is vapor deposited on the base coat.

However all these are pure R&D level aleast in India ... Khan's world beating tech surely uses it, otherwise achieving 1500+ deg C TET in it's various current turbofans etc is not possible.
All DRDO has done is devised a way of manufacturing these LZ based bilayer TBC stuff and used them on static components in the A/B etc
- pls refer to my earlier posts, from some years back on all these aspects, for further details.
And moreover, applying it on a high-rpm rotating component like HPT blade, will require further back (and bank) breaking R&D etc ... so that's where we are, as far as I know (other folks from DDR etc will obviously know much better).
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

That brings us to another research prospect. Composite vanes and shrouds. It took GE nearly 30-35 years to prove composites enough to put them in engines as shrouds for the hot sections. We have programs too but obviously they'll take time. Material, coatings, machinability, fatigue etc will all need to be studied in depth for even prototypes to come about, let alone putting it into an actual engine. Time & money :)
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

Rakesh wrote:Prasad, I am truly in awe of the excellent work you, Saurav Jha and others do at DDR. Really exceptional.
You're very kind. It is just something anybody here could do.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Neela »

maitya wrote:
But I've digressed again, but since already done, so let me add just one more point (a question) to it:
viz. being a product of an global turbofan producing powerhouse, why on earth would the TeT of the mighty AL-31F be limited to 1300deg C etc, while a pure-SDRE Kabini manages 1455deg C? Hain jee, please think thru ...


.
AL31F does not have blade cooling whereas Kaveri does? Since DS limit is 1050C, and TeT is 1455, isnt that the only explanation.

Thanks Maitya. This second post was really helpful to understand.
Summary of key posts for anyone having an hour or so to assimilate all the info. Read them in this order

viewtopic.php?f=3&t=3351&p=2367572#p2367568
viewtopic.php?f=3&t=3351&p=2367572#p2367570
viewtopic.php?f=3&t=3351&p=2367572#p2367572
viewtopic.php?f=3&t=3351&p=2372973#p2372973
maitya
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Re: Kaveri & Aero-Engine: News & Discussion

Post by maitya »

Neela wrote:
maitya wrote: ...
But I've digressed again, but since already done, so let me add just one more point (a question) to it:
viz. being a product of an global turbofan producing powerhouse, why on earth would the TeT of the mighty AL-31F be limited to 1300deg C etc, while a pure-SDRE Kabini manages 1455deg C? Hain jee, please think thru ...
...
AL31F does not have blade cooling whereas Kaveri does? Since DS limit is 1050C, and TeT is 1455, isnt that the only explanation.

Thanks Maitya. This second post was really helpful to understand.
Summary of key posts for anyone having an hour or so to assimilate all the info. Read them in this order

viewtopic.php?f=3&t=3351&p=2367572#p2367568
viewtopic.php?f=3&t=3351&p=2367572#p2367570
viewtopic.php?f=3&t=3351&p=2367572#p2367572
viewtopic.php?f=3&t=3351&p=2372973#p2372973
Thanks Neelaji ...
Yes had written that 4-part series, way back in 2019, to bring out the importance of the allied technology on HPT blade design/manufacturing, than this single-minded-obsession wrt SCB etc.

Yes Casting technology is very important, but certainly not the be all and end all, of HPT blade design/mfg aspects ...
Other technologies like convectional cooling (and also internal-blade cooling tech), TBC, even the geometry of the blade structure, the complex CFD of gas-flow between vanes and the turbine, even the shrouds etc etc are quite critical aspects.

It is the sum-total of all these highly complex and strategic (and thus jealously guarded via multi-layer IPRs) technologies that helps achieve a Turbofan core these much-publicized TeT figures etc.

The irony is in the question that I'd asked ... how come a piddly SDRE turbofan core of Kabini with it's oh-so-outdated :roll: DS casted HPT blades achieves 1455deg C TeT, while the uber SCB-casted AL-31F struggle at 1300-1320 deg C TeT levels.
Answer is the degree of application of the above-mentioned technological aspects.

To put it succinctly, in a summary mode, let me quote a line from this post of mine (from back in 2019), that you've quoted above:
...
So Kaveri's DS blades gets to 1455 deg C via 1050 deg C (DS Cast) + 250 deg C thru blade cooling + 150 deg C via 8YSZ based TBC.
...
arvin
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Re: Kaveri & Aero-Engine: News & Discussion

Post by arvin »

https://www.ch-aviation.com/portal/news ... conversion
HAL said it was also evaluating acquiring B747-400s retired by Air India and converting them into freighters. The Indian flag carrier owns four of the Boeing quadjets which were retired in 2020 and 2021 and eventually deregistered as of May 1, 2022. They remain parked at Mumbai Int'l airport.
If the above news is true hope some one in HAL also realizes the posibility of converting atleast one of them into flying test bed.
ramana
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ramana »

arvin, These 747-400s are for IAF already allocated before the sale to Tatas.
Its DRDO will get the flying test bed so can be used across entities.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

I don't know where else to post this...

https://twitter.com/alpha_defense/statu ... sdxe97AQ4Q ---> CEO of French aircraft engine maker SAFRAN Group calls on Raksha Mantri Shri Rajnath Singh in New Delhi. The company announces plans to set up a Maintenance, Repair and Overhaul facility in India.

https://twitter.com/alpha_defense/statu ... sdxe97AQ4Q ---> RM invites SAFRAN for more such co-development & co-production projects in line with ‘Make in India, Make for the World’.

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Rakesh
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

https://twitter.com/ReviewVayu/status/1 ... 8lOhAWRqVg ---> Safran inaugurates its third plant in India in 2 days -- this time at Bangalore for Safran HAL Aircraft Engines, a 50/50 JV between @SafranEngines & @HALHQBLR. New site replaces the initial plant that dates from 2005, more than doubling the area and featuring state-of-the-art installations. It’s located in a Special Economic Zone near the Bangalore airport. Spanning 11,000 square meters (118,800 sq ft), the plant makes complex piping, mostly for the @CFM_engines LEAP engine, and has about 150 employees.

https://twitter.com/SAFRAN/status/15453 ... SLQPM9a_aA ---> Immersion in @SafranEngines new facility in Hyderabad, dedicated to making rotating parts for the #CFMLEAP engine from @CFM_engines!

To provide the additional capacity needed for a production ramp-up for the LEAP #engine.
* 162,000 square feet.
* 250 people.
#MakeInIndia

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