Kaveri & Aero-Engine: News & Discussion

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

Post by chetak »

Please do not get carried away by this MNCs and their India based R&D stories.

Some relatively low end work is undoubtedly going on.

The local teams are purposely fragmented and carefully isolated physically so that no one person is able to see the bigger picture. There is no cross pollination and the data is stored as well as backed up offshore.

That is exactly how they have set it up, it's what they want and they are paranoid to keep it that way.

Even the local networks are not connected to each other.
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Post by Picklu »

chetak wrote:Please do not get carried away by this MNCs and their India based R&D stories.

Some relatively low end work is undoubtedly going on.

The local teams are purposely fragmented and carefully isolated physically so that no one person is able to see the bigger picture. There is no cross pollination and the data is stored as well as backed up offshore.

That is exactly how they have set it up, it's what they want and they are paranoid to keep it that way.

Even the local networks are not connected to each other.
Oh absolutely, i am not denying that the local guys do a minuscule thing in the overall scheme of things and they are purposefully disjointed.

The point that i was making is that their work is still top notch and the investment and structure behind them is what is required for the success and our current socio-governmental setup and access level to cheap capital is nowhere close to provide it.

We need to find alternate path and no point blaming either the corrupt govt or the lazy scientists; the malaise is far more systemic and not always in our control
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chola »

This includes a lot of what we discussed here but this twitter thread explains the urgency of needing to have a clear plan for an indian engine in stark terms.

https://mobile.twitter.com/Aerodynamic1 ... 1945751552
Aerodynamics
@Aerodynamic111
IAF will have operating nearly 395+ F414+F404 engine by 2035 with 0 local production of spares, even if IAF never inducts any US jet, leaving the IAF fleet vulnerable to sanctions and restriction on the supply of spares, in the event of the fallout of relationships with US
...
So, India not to be depended on American developed F414/F404 family engine will need to develop at least two engine variants that can be locally developed with a foreign aero-engine maker. India should strive to develop a de-tuned 100kN thrust class engine
...
+MWF and Tejas Mk1A fleet will require 3.5 engine swap for its entire flight worthy life of nearly 40yrs so India will neither sud upgrade the fleet of Tejas MkII and Tejas Mk1A fleet wth the same 110kN engine we plan to develop for the AMCA MkII or
...
++we can plan to develop a de-tuned variant of the same engine with lower thrust, Selection of the same 110kN thrust class engine for all 3 programs will mean that the production rate of the engines will be high and due to the commonality of engine among all 3 fighter jet fleet,
...
++logistics and maintenance of the jets at a base level will also improve considerably. India will require at least 10 years for the new engine to be ready for the production so, in next two to three years, India will need to take a call on development partner it ws to choice fr
...
+++the new engine and also invest in the required infrastructure like flying test-bed and multiple rig and ground engine facility for the program to succeed.
If we do not invest in an indigenous engine -- whether it is the Kaveri or a new project -- and the infrastructure behind it then we will always be beholden to the whims of others.

We need to make a call soon. The lead time in these things are long. This is like our carrier program. Without a decision, the future path is uncertain because it will take more than decade at least even if we start today.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by kit »

chetak wrote:
chola wrote:
Thanks for your reply and your relating your experience, Saurabh ji.

So my question is what now? Can we wait for home ground tools industry to mature before we try again with a new engine? That sounds too far into the future.

Should we just pony up the money to the French and bring in their M88 core to help us bridge the gap for now? Do we have a choice? Unless we are satisfied with just importing F414s.
The F414 is a landmine that is politically sensitive to untimely detonation, especially in times of maximum need.

the expiry date on such products is never mentioned.

A new POTUS can easily mean a new policy that may impact us like a savage jab to the solar plexus. The US deep state has never been India friendly ever. Since 1947, they have always preferred the immorally pragmatic, corrupted, transactional and "for sale" paki establishment which mirrors their own national philosophy as demonstrated so openly and ably in their saudi + gulf relationships.

the amerikis have been at the vanguard of engine technology denial to India for decades now.

Only ISRO (and DAE) have so far managed to wriggle out of their deadly embrace.

this military jet engine is proving a hard nut to crack with a cartel of countries ganging up on us to ensure that we do not make any progress in this domain.
The best way is to get the current engine flying and powering a test bed. Nothing else. No need to wait for fancy iterations now.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Raghunathgb »

Good news after long time.

DMRL’s expertise in investment casting technology has also resulted in a civilian spin-off for the manufacture of large size blades used in land-based turbines for power generation (BHEL and NTPC). NTPC is operating several gas-based power plants in the country and the blades for gas turbine engines are being imported at high cost to replace the worn/damaged blades during the overhauling. With the help of CAD model, a wax pattern injection die has been designed and fabricated. It was quite challenging to produce a class-I casting since the individual blade is heavier (3 kg) than the Kaveri aero-engine blade (200-300 g) produced so far. However, with existing expertise of developing aero-engine blades, technical difficulties were overcome through optimisation of process parameters. One engine set, consisting of 125 numbers of IN738 alloy blades, was produced with an acceptable yield of 60 per cent and handed over to NTPC. This is an outstanding example of civilian spin-off benefit of the technology developed for defence.


DMRL has developed the process technology for making highly intricate, aerofoil shaped, sintered silica cores used for the production of hollow gas turbine engine components. This is one of the critical material processing technologies in the gas turbine engine development programme. Through sustained research and development efforts, a viable process based on Ceramic Injection Moulding (CIM) has been successfully developed. The capability of the process has been demonstrated by making highly complex and intricate ceramic cores meeting stringent dimensional requirements. The process is used for making silica cores for production of turbine blades and vanes of Kaveri engine and land-based gas turbine. The process is also being adopted for preparing alumina cores required for producing single crystal aerofoil castings.
https://www.drdo.gov.in/large-aerofoil- ... ne-engines
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Post by Raghunathgb »

The above shows that even a failed project can create lot of spin-offs and positive stories(I will still not declare it sucessfull until bhel starts using it) . This will keep project alive as many technologies used for Kaveri engine will ultimately end in various other sectors thereby multiplying it's value.
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Post by Picklu »

While we should accept even a 20% yield, what's the global standard in this case, compared to the 60% yield mentioned above?

This would give us an idea about how much further improvement we need to do.
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Post by fanne »

does the word 60% yield here means that out of 100 blades made, 60 passed QA?
Raghunathgb
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Post by Raghunathgb »

fanne wrote:does the word 60% yield here means that out of 100 blades made, 60 passed QA?
My uneducated guess is thermal efficiency. If that's the case it should be good enough.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Indranil »

fanne wrote:does the word 60% yield here means that out of 100 blades made, 60 passed QA?
In my industry (of semiconductor), it is.
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Post by ramana »

fanne wrote:does the word 60% yield here means that out of 100 blades made, 60 passed QA?
Yes. Production process yield.
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Post by fanne »

thx bandhus...60% is good. I wonder what is it for more exacting standards, such as Kaveri blades or AL-31 F blades.

Th path anyways goes this way - 10% then 20% the....and eventually high 90s %
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Re: Kaveri & Aero-Engine: News & Discussion

Post by JayS »

Just to put things in perspective, I remember to have read that the OLED screens had about 16-18% yield that too with repairs, and that was key reason that they were not coming up in TV space. This was a few years ago. Now the manufacturing must have been fine tuned. Engineering is all about doing it in iterations and improving it a step at a time in every iteration. Our problem is we don't do iterations.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chola »

JayS wrote:Just to put things in perspective, I remember to have read that the OLED screens had about 16-18% yield that too with repairs, and that was key reason that they were not coming up in TV space. This was a few years ago. Now the manufacturing must have been fine tuned. Engineering is all about doing it in iterations and improving it a step at a time in every iteration. Our problem is we don't do iterations.
I second the point. The US Gov. Accountability Office back in 2016 said "F-35A and F-35B engines are still at about 55 percent and 63 percent":
https://www.courant.com/news/connecticu ... story.html

This is from a premier engine maker (P&W) with massive experience in the midst of a gargantuan production run for thousands of 5th gens. Even they are going through tuning in mass production mode. This is what industries do.

We don't do iterations goes back to the fact that we do not have an industry but a lab building our engine programs.

Things in production can't be fixed in "theory" in a lab. Once an engine is tested enough for minimal viability it really needs to be put into an assembly line and fixed through iterations.

I believe that Kaveri was minimally viable a decade ago at Gromov when it ran for 57 straight hours. But we never production-ized it to any extent with a variant of the LCA or a safer two-engine design -- maybe a desi Fulcrum.
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Post by Neela »

JayS wrote:Just to put things in perspective, I remember to have read that the OLED screens had about 16-18% yield that too with repairs, and that was key reason that they were not coming up in TV space. This was a few years ago. Now the manufacturing must have been fine tuned. Engineering is all about doing it in iterations and improving it a step at a time in every iteration. Our problem is we don't do iterations.
Sir, GaN ICs for commercial purposes is yet to reach mainstream. High frequency operation, High temperature stability , ultra low form factor - all of these have been proven . It makes it very appealing for server farms ( less cooling ) , LED ICs, AC/DC converters - a whole range of applications. However, yield is low ~50%. (Still way better than <10% few years back. ) This makes the business case unviable. Yet, foundries, startups etc invest money to understand the manufacturing process, understand failure causes, come up with better manufacturing techniques etc. The expectation is that by 2025 , we should see it appearing commercially.
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Post by Rishirishi »

Raghunathgb wrote:The above shows that even a failed project can create lot of spin-offs and positive stories(I will still not declare it sucessfull until bhel starts using it) . This will keep project alive as many technologies used for Kaveri engine will ultimately end in various other sectors thereby multiplying it's value.
The prime example of this is Bangalore. Had it not been for the investments made in defence, Bangalore may not have happened.
Money spent in trying to make stuff never goes down the drain. Some people learn stuff, some people sell stuff and some people get new ideas.
Gerard
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Gerard »

FOREIGN RELATIONS OF THE UNITED STATES, 1964–1968, VOLUME XXV, SOUTH ASIA

21. Message From Robert Komer of the National Security Council Staff to the Ambassador to India (Bowles) - Washington, February 27, 1964.
Bundy and I can’t help but feel that Orpheus engine for HF–242 is our secret weapon for sidetracking Soviet MIG and possibly SAM deals.3 You yourself have pointed out how going ahead with HF–24 would also pander to Indian nationalism, while being the course least painful to the Paks. This track is also a lot easier than SAMs from here, which are out.

We understand that if UK would only get Bristol to put two of the test engines into flyable conditions, it should cost less than $1 million. Bristol of course is holding out for commitment on full develop ment [Page 47]and tooling up cost first but surely HMG could make them see the light. Why shouldn’t this be top priority claim on UK military aid?

We’ve been touting this here, and have gotten DOD to raise in London. But it badly needs another big push from you and Gore-Booth now, if we’re not to shut the barn door just after the horse is gone. Needless to say, our intervention is private to you.4
https://history.state.gov/historicaldoc ... -68v25/d21
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Post by sivab »

https://economictimes.indiatimes.com/ne ... 101751.cms
Is development of an indigenous fighter jet engine a priority?
DRDO chief: Yes, it’s a priority for strategic autonomy. The development of an indigenous jet engine through the Kaveri programme has boosted the know-how and industrial ecosystem in the country. Presently, we are working on the flagship programme to develop an Advanced Medium Combat Aircraft. It requires an advanced 110kN thrust class engine. We will involve academia, industry and defence PSUs to develop this high-thrust engine. We are open to international collaboration.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chola »

^^^ I hope us success.

But I somewhat think we are again shooting for the moon. When we started on the Kaveri back in the 1980s we tasked GTRE with building an elite medium class turbofan that even the Russian had a hard time with in the RD-33 -- when we've never even developed a production turbojet. Now we are asking for a 110kN medium engine that even the Amreekis and Russkis do not have at the moment.

The F404 (and Kaveri) were spec'ed at 80kN. Even the Al-31 a heavyweight class on our MKI is only rated at 123kN. At any rate, I think we have learnt enough from the LCA to not couple the airframe with the engine. The AMCA can continue with the F414 (100kN) but it still worries me that we are setting ourselves up for another Kaveri in the engine department. Once again our ambition is grand instead of realistic?
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Aditya_V »

It is also the Kanjus nature of bean counters in India., better to buy Test bed planes and develop a family of Engines with varying sizes, so even if are not able to come up with best of materials/ Metalurgy, we can have something slightly oversized but works- and with none of the Flat rating BS. I am not an expert but how many engines are flat flat rated, is the AL31FP flat rated, M-53 flat rated, RD 33 and RD 93 flat rated??
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chola »

I think we've chosen a harder path for ourselves with these lightweight airframes in the LCA and now AMCA. Supposedly when we envisioned them during design that they would be cheaper to produce but the engine required to power them need to be light as well and we envision these advanced thrust requirement in that smaller powerplant which means more pressure/heat per inch than a larger engine.

HAL makes 70% of the AL-31. I sometimes think we could have gone for a heavyweight desi 5th gen as a followon to the MKI and leverage that engine experience. We were planning for a heavyweight 5th gen in the FGFA anyways.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chetak »

USAF Research Lab builds an ‘open source’ jet engine in 13 months


12 NOVEMBER, 2019

The US Air Force Research Laboratory (AFRL) says it has designed, built and tested an “open source” engine in 13 months.

The AFRL says its Responsive Open Source Engine was tested for the first time on 6 November at its headquarters, Wright-Patterson Air Force Base.

The small jet engine was built by the Aerospace Systems Directorate and is the first turbine designed, assembled, and tested exclusively in-house, says AFRL.

The lab did not disclose the jet engines thrust rating, though the small turbine appears to be sized to fit into a small unmanned air vehicle (UAV) or cruise missile.

The AFRL developed the engine in-house to test the theory that it could create engines faster and cheaper than private companies.

“We decided the best way to make a low-cost, expendable engine was to separate the development costs from procurement costs,” said Frank Lieghley, Aerospace Systems Directorate Turbine Engine Division senior aerospace engineer and project manager.

The US Air Force (USAF) owns the design and intellectual property of the small engine. “Therefore, once the engine is tested and qualified, the Air Force can forego the typical and often slow development process, instead opening the production opportunity to lower-cost manufacturers better able to economically produce the smaller production runs needed for new Air Force platforms,” the service says.

The AFRL says high costs for developing small jet engines have held back the creation and use of new aircraft. The lab is aiming to cut the cost of developing such turbines by 75%.

“There’s no end to what might be done, but it’s all enabled by inexpensive production,” says Greg Bloch, Aerospace Systems Directorate Turbine Engine Division chief engineer. “It’s the ability to turn the economics of warfare around.”

The AFRL did not say how it was able to develop its Responsive Open Source Engine so quickly and for less money, though the process centered on empowering a small team of engineers to handle the entire process.

That method echoes a similar development effort by Pratt & Whitney’s (P&W) prototyping arm, GatorWorks. The company recently gave a team of about 15 hand-picked employees three performance specifications around which to develop a small turbine. By focusing only on thrust-rating, cost and size, the team was able to create a new engine core that was designed, built and tested in less than a year.

P&W and AFRL are responding to demand for faster and cheaper engine development from the USAF. The service envisions hordes of low-cost missiles and attritable UAVs that can overwhelm, dodge or outdistance Chinese and Russian air defence systems. It needs cheaper and higher performance engines to power that strategy.

The USAF's attritable concept comes from the word "attrition," meaning aircraft built cheaply and quickly enough to be affordably lost to attrition in combat.

The AFRL has said it plans to invest up to $725 million in jet turbine research and development between fiscal years 2018 and 2026, through its Advanced Turbine Technologies for Affordable Mission programme.

Beyond faster and cheaper development of engines, the AFRL also notes that giving its employees hands-on experience has other benefits.

“By teaching our people to do this themselves, we’re instilling in them a level of gravitas that will serve the Air Force well when we then apply that oversight to the traditional engine manufacturers,” says Bloch.

The AFRL says it is analysing data from its first engine test and plans to build a second version of the engine that will be smaller and lighter. The lab says with the tools and knowledge it gained from the first engine it should be able to finish the second engine in less time.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Rakesh »

https://twitter.com/SJha1618/status/1196796346432278529 ---> Hopefully, New Delhi has understood why India needs an indigenous fighter class low-bypass turbofan in the 110-120 kN category by *hook or by crook*. Any further equivocation on this matter will completely belie any claims to becoming a major power/great power yada yada yada.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ramana »

I don't know why use such words. India won't get by hook or crook.
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Post by chola »

Rakesh wrote:https://twitter.com/SJha1618/status/1196796346432278529 ---> Hopefully, New Delhi has understood why India needs an indigenous fighter class low-bypass turbofan in the 110-120 kN category by *hook or by crook*. Any further equivocation on this matter will completely belie any claims to becoming a major power/great power yada yada yada.
Again 110kN is an extremely tall order for a medium class engine needed for the AMCA. Even a heavyweight engine like the AL-31 for our MKI is 123kN.

Right now neither the US nor Russia have a medium engine of that power. The closest is the F414 at 100kN. The F404 powering the Tejas is at 80kN. We can't even RE something. We need to leapfrog the Amreekis and the F414.
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Post by prasannasimha »

I think we must build separately some engine as a science project that works and build a plane around it. This way we will get out of the long term cgicken and the egg situation. The science project continues to evolve the engine in stages
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Post by habal »

chola wrote:Again 110kN is an extremely tall order for a medium class engine needed for the AMCA. Even a heavyweight engine like the AL-31 for our MKI is 123kN.

Right now neither the US nor Russia have a medium engine of that power. The closest is the F414 at 100kN. The F404 powering the Tejas is at 80kN. We can't even RE something.
that for you is confidence.

Even earlier we have been hearing this figure of 100Kn+ being thrown around. Surely there is some substance to it. Some rudimentary tests, wind tunnel tests of a new gen engine well has produced this level of output for this figure to start floating.

I personally think, some building blocks are there for a 110Kn engine. We have indeed shot ahead in some areas and in some areas we lag. We need to collaborate with the french or rolls-royce or IHI Japan or even the ukrainians to fill in the gap which has been thus created.
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Post by Kakarat »

Exclusive Updates From The HAL Tejas Mk1 & Mk1A Programmes - DDR
On engine development
Now as is known, the entire Tejas Mk1, Mk1A and Mk2 i.e. MWF fleet will be equipped with General Electric F404 and F414 series engines. The Kaveri programme has as such failed to deliver a viable domestic engine that can meet the thrust requirements of even the Mk1. Although, the Gas Turbine Research Establishment (GTRE) has been able to achieve the targeted dry-thrust in the Kaveri engine it has not been able to meet the wet-thrust requirement. Presently, efforts to make use of single-crystal turbine blades developed by Defence Metallurgical Research Laboratory (DMRL) as well as research into afterburner design is underway at GTRE to ‘fix’ the Kaveri design. Unless, an indigenous engine becomes available when it does, there is currently no plan to develop alternate engine sources for the fleet.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by SaiK »

Who wrote that article last month on DDR? I was thinking it was Nilesh & Sriram. I doubt it is not. Anyway, please whoever, provide details.
Presently, efforts to make use of single-crystal turbine blades developed by Defence Metallurgical Research Laboratory (DMRL) as well as research into afterburner design is underway at GTRE to ‘fix’ the Kaveri design./
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Post by Prasad »

That is the last bit of info we have SaiK. No further information. GTRE is clammed up and we have no information about feedback about these blades yet. So poruthar bhoomi alwar.
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Re: Kaveri & Aero-Engine: News & Discussion

Post by maitya »

Prasadji, have highlighted the operative word of the below quote:
... Presently, efforts to make use of single-crystal turbine blades developed by Defence Metallurgical Research Laboratory (DMRL) ...
As we all know we have had lab-production-level DMS4 based (4th Gen) SC blades from atleast 2015 onwards ... pls refer to the very old picture of DMRL produced SC blades ...Image


Also do refer to this chart (again very very old) ... Image


Now, if you look at the dark-blue column in between, you will see how the Dry and Wet thrust levels can be enhanced by the classical "hot-section improvement route" i.e. without tweaking the inlet geometry and other physical/geometrical aspects etc too much,

1) first increase the TeT of the HPT (both blades and vanes)
THEN
2) matching it with an OPR increase by improving SPR for BOTH the HPC and the Fan stages
---------------------------------------------------------------------------------------------------------------------------------------------------------------
1) for improving SPR of the Fan Stages, the LPT itself needs improving.
2) while looking at the chart figures, pls ignore the absolute Thrust values mentioned in it - instead compare % improvement achieved and draw your own conclusions.


Aka a complete re-design of the core - and gazillion years (and money) of dedicated and iterative testing etc.

For comparisons, Kabini currently is at 1,455deg C (or 1,728deg K) TeT level - while M88 is at 1,850 K (1,580 °C) - so ~125deg improvement is required.

TeT improvement from pure material would be ~30-40deg levels - remaining 100 odd deg improvement have to come from utilizing the superior thin-wall etc properties of a typical SC casted blades/vanes and implement,
a) better various Blade Cooling techniques (e.g. Film/Convection cooling)
b) Thermal Barrier Coating (TBC) application

etc etc etc.

:(( One of these days I'll be able to get some b/w and finish my latest write-up regarding all these ... Sigh!! :((

Until then ... maybe this very very very old post of mine may provide some details.
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Post by Prasad »

Yes sir. Specifically these blades have the ysz tbc-coating by ebpvd done at arci with cooling holes.
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Post by maitya »

Prasad wrote:Yes sir. Specifically these blades have the ysz tbc-coating by ebpvd done at arci with cooling holes.
Actually I's hoping (against hope and almost a wet dream) that GTRE would take the easy way out and go for a LZ-YSZ bilayer TBC tech for both HPT and LPT blades and vanes, without delving too much into blade-geometry changes or redesigning of the current impingement and convective cooling design etc
The tech for improving Film/Convection cooling scheme (and also the internal cooling passages for impingement cooling etc) is as cutting edge (laser drilling, "black-art" of S&W avoidance etc) as it gets and also at best, very incremental in nature.

On the other hand, recent breakthrough at IERL for the LZ-YSZ bilayer TBC tech application should enable GTRE/DMRL to get the existing DMS4 based SC blades coated (via ebpvd etc) with this bi-layer and quickly add 100deg to the TeT - and be done with the turbine part of it.

Details of LZ-YSZ bilayer TBC can be found here and here.

Yes it wont be super duper 1600+ deg C level tech, but 1560-1580deg C level will be quite within reach (and let there be a Kaveri-III for 1600-1650 deg C level TeT beast as a future gen etc).

And instead focus on increasing either OPR or atleast the mass-flow rate or both, via redesign of the Fan/LPC stages - and if possible go for different wide-chord blade geometries etc for the HPC stages. Just like what GE did with the 1st Gen F414s (that were derived from F404 without touching the HPT and LPT).

It is much less risky that way ... but then again, above is just a layman's musings bordering wishful thinking etc. :oops:

Added Later:Links to some of my old posts on LZ-YSZ bilayer TBC etc.
Last edited by maitya on 17 Dec 2019 00:44, edited 1 time in total.
ArjunPandit
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Re: Kaveri & Aero-Engine: News & Discussion

Post by ArjunPandit »

folks there was an article on IDRW that HAL will have its own Su30. Can't some of them be used as test beds for kaveri..I understand it can't replace the Al31, but is it completely impossible to ..fit the engine externally...
Prasad
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Prasad »

Maityaji
I've read the paper and spoken to people involved. The lanthanum zirconate tbc was for something else entirely, With no plans (afaik) to try it on blades at the moment. And if you notice it was deposited by sps. So there would be a need for studying pvd (atleast a year). Or atleast that is what i gathered. Drilling holes is also 'not a problem'.
Thakur_B
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Re: Kaveri & Aero-Engine: News & Discussion

Post by Thakur_B »

Image

Purported image of the K10 engine model. Credits to Porky Kicker on DFI.
sivab
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Re: Kaveri & Aero-Engine: News & Discussion

Post by sivab »

^^^
Wrong credit. It is from a tweet by PM himself.

https://twitter.com/narendramodi/status ... 1814089729

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

Post by habal »

that is one clean looking engine. I have to admit this, I love the incremental way our scientists scrape and nibble at improving their turbofan tech without much hype and hoopla at x variations and n+1 iterations. At some point of time in future they will come up with a credible and high-performing engine that is comparable to the median western tech available at that point of time.
chola
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Re: Kaveri & Aero-Engine: News & Discussion

Post by chola »

habal wrote:that is one clean looking engine. I have to admit this, I love the incremental way our scientists scrape and nibble at improving their turbofan tech without much hype and hoopla at x variations and n+1 iterations. At some point of time in future they will come up with a credible and high-performing engine that is comparable to the median western tech available at that point of time.
Sir, I'm sorry but one cannot love an incremental lab process that has taken nearly three decades. It would be one thing if it were in even limited production today but right now there are still no more than a handful built in a lab basically.

That said, what the GTRE scientists did was amazing when compared to most of the world. Not many had gotten a medium turbofan to the testing phase including countries that built aircraft for decades like Brazil, Sweden or Germany.

But if we are not taking that next step into production then this work could be all for naught. Our main competitor is not Brazil or Sweden but Cheen and Cheen puts many engines into production.
RKumar

Re: Kaveri & Aero-Engine: News & Discussion

Post by RKumar »

They have major issues with all their engines as well as earlier copies of J-10 and J-11, it is one thing to have lot of money and spending it on immature products. I agree they have mastered the art of mass production but their basic r&d is limited to stealing the know-how. And by stealing you can learn only to an extent.
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