Kaveri & Aero-Engine: News & Discussion

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Sagar G
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Re: Kaveri & aero-engine discussion

Post by Sagar G »

pentaiah wrote:Pentaiah
So does you being "Pentaiah" gives you some kind of miraculous right to derail this thread by coming and making fanboyish statements of "I want this engine or that" ??? As if by posting about what "you" want is going to propel India into the exclusive club of aero engine manufacturers.

It's very much clear where India's efforts are in regards to aero engines so being a senior poster you must post more responsibly.
pentaiah
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Re: Kaveri & aero-engine discussion

Post by pentaiah »

Neither do you have miraculous right, if you did I implore you give the engine I will run with it on a broom between my legs no?
Sagar G
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Re: Kaveri & aero-engine discussion

Post by Sagar G »

Even if I had any miraculous right why would I give the engine to you ??? His highness can use the same engine he has displayed to fulfill his harry potter dreams.
SaiK
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Re: Kaveri & aero-engine discussion

Post by SaiK »

Okay, when a person says I want this or that it does not mean he/she expects somebody to home deliver to him/her any real engine from GTRE. I guess it is an idiom that one might want to express their wishes. There is nothing wrong with that wish. After all threads are built based on such jingo powers.

The thread derailment happens only if you satisfy that wish, and not GTRE. BTW, that is another way to any person to participate in free speech. It could be seen as such wishes may be fanboyish, and outside the scope of the project, but as long as it is within the scope of the thread then it should be acceptable.

Not supporting anyone here now.
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Re: Kaveri & aero-engine discussion

Post by Yagnasri »

Kaveri going to be tested on the other older versions of LCA ??? There was also news item that soon Kaveri powered LCA will be made for testing purpose. There was some idea posted in this tread that Kaveri can be tested on Mig29 first etc. There is news on this later on. It would be great to see that happen.
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Re: Kaveri & aero-engine discussion

Post by Singha »

One of the tejas which was originally sized for kaveri will be kept for kaveri test flights by hal. That is confirmed in interview with higher up in ada.

The ball is in gtre court now how soon they can get kaveri ready for tejas after concluding the il76 testbed work.
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Re: Kaveri & aero-engine discussion

Post by NRao »

There is an effort to mate a Kaveri to a LCA, BUT, that is NOT related to the two (LCA and kaveri). It is meant to test the Kaveri for a UAV, etc. The LCA is just a plain, simple test platform. Once tested the plan should be to discard the LCA from the picture.
Indranil
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Re: Kaveri & aero-engine discussion

Post by Indranil »

Some guess work here based on the Tender for Procurement of forgings put out by ETBRDC, HAL.

I am guessing that the 20 KN engine is called HTFE-25, which probably stands for Hindustan Turbo Fan Engine. The number 25 is confusing. Is it going to be a 25 KN engine?

It has 5 HPC stages and 1 LPC stage?
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Re: Kaveri & aero-engine discussion

Post by vic »

indranilroy wrote:Some guess work here based on the Tender for Procurement of forgings put out by ETBRDC, HAL.

I am guessing that the 20 KN engine is called HTFE-25, which probably stands for Hindustan Turbo Fan Engine. The number 25 is confusing. Is it going to be a 25 KN engine?

It has 5 HPC stages and 1 LPC stage?
What happened to the ToT obtained by HAL from contracts of Al-31, Al-55, Adour etc?
Austin
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Re: Kaveri & aero-engine discussion

Post by Austin »

vic wrote:What happened to the ToT obtained by HAL from contracts of Al-31, Al-55, Adour etc?
TOT for any product helps you to maintain the products better at your end , it wont help you to build something new or use technology for other products thats not related to original product.
Will
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Re: Kaveri & aero-engine discussion

Post by Will »

Lets all come back in 20 years and discuss this :(
NRao
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Re: Kaveri & aero-engine discussion

Post by NRao »

Folks,

There are NO short cuts WRT engines.

ToT may or may not help, more than likely the latter. Example: The alloys provided in a ToT may not work in an Indian engine, while SCB or whatever else techs may work just fine. AND, it could years to find a good alloy. With no one willing to provide any help.

I am hoping that in 20 years India will have a mature engine base. That the questions will remain the same, BUT that the engine will be leading edge for that time.
Last edited by NRao on 04 Apr 2013 19:24, edited 1 time in total.
pentaiah
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Re: Kaveri & aero-engine discussion

Post by pentaiah »

Make simple rice before making biryani that too hyderabadi

Make simple late 60s engine make some simple piston aircraft and jet engines of Gnat era
Make them pucca for reliability and maintenance

Then talk of Scb and its grand sons
Save some simple money going to Swiss Alps, Bahamas beaches
Use that money into large scale R&D in multiple institutions not GTRE which can't gate crash to RRF Orpheus engine
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Re: Kaveri & aero-engine discussion

Post by NRao »

pentaiah,

What is exactly wrong with the Kaveri they have?

Am I missing something?
SaiK
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Re: Kaveri & aero-engine discussion

Post by SaiK »

yes.. big time you are missing. we have to first have an operational home grown engine first. no matter what technology, thrust to weight or capabilities. we need a base line. mandatory.

and then we can derive progression chart, and have some tractability and meaningful reference. kaveri on LCA is a must.. it should have happened years back. it is a mute point advancing the thrust weight, when we have not even made the first step. would it not irritate any jingo!?!?

need of the hour is whatever t:w kaveri, must be inside one of the LCAs. MUST MUST MUST.
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Re: Kaveri & aero-engine discussion

Post by NRao »

OK, since we are not on the same page, let me rephrase:

pentaiah,
Make simple late 60s engine make some simple piston aircraft and jet engines of Gnat era
WRT to the above, what is exactly wrong with the Kaveri they have?

(I do not think I am missing anything.)

On "operational", having been through this plenty of time, WRT to what? Certainly not WRT to a Gnat!!!
pentaiah
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Re: Kaveri & aero-engine discussion

Post by pentaiah »

Let me try one more time
Kaveri is state of the art ok nearly state of the art engine

Have we had any experience in successfully developing from scratch a jet engine
The last time I jumped up and down was when I was in late teens when HAL announced
A jet engine called HJE 2500 I saw this in films division news real before watching a movie called Love in afternoon and the movie hardly had an kissing scene to satisfy a teenager, so was this HJE 2500
Nothing came about it

Ok can any one do curl div etc computations with out
Vector calculus?

Can some one do Laplace transforms with out
Differential and integral calculus

Can some one do Fourier transforms with out
Linear algebra course?

Can some one do de Moivres theorem with out
Exponential series and bi nominal expressions understanding?

If yes then we have Kaveri running into TN capable delivery systems


Of course we have a pretty picture of HJE 2500 which went from test bed to museum straight away not in flying condition but pitch forked into position. Looks neat with all wireless hydraulic components
Image

Image

Both the above had massive star power but never box office hit
Notice
Audrey Hepburn may be a case of Wait until Dark also starring Audrey
NRao
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Re: Kaveri & aero-engine discussion

Post by NRao »

I find it very hard to read/understand both, your and Sai's, posts. You guys tend to ramble. (Reminds me of the physics prof who started his class talking about surface on earth (topic of the lecture) .......... moved to air on earth. Atmosphere - made of troposphere, stratosphere, ......, ionosphere, ................... space, ................. no atmosphere on moon ......................... ended class with surface of moon.)

Anyways.
Kaveri is state of the art ok nearly state of the art engine

Have we had any experience in successfully developing from scratch a jet engine
Well, Kaveri is from scratch. Am I wrong (anyone)?

Most, if not all, engines need to be from "scratch".

The most relief provided by any external process is ToT, but even they come with clauses that prevent one from transferring the technologies to other in-house efforts. Which forces the issue of being from scratch.

IF one were to reverse engineer an engine the effort runs into problems because of alloys, manufacturing, etc. Scratch.

IF one reverse engineers an engine and makes a change, the change introduces dimensions never visited. Scratch.

The only -ve I find with the kaveri is the expectation set by someone out there on that team. Else this machine is just fine. India could have managed it better, for sure. But technically it is mature enough, the problems encountered are normal, to be expected.
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Re: Kaveri & aero-engine discussion

Post by SaiK »

so, getting the existing kaveri configuration as designed and as tested to specs, into LCA is a milestone. I am not sure, out in the DDM we hear more about this rather than asking for LCAMK2/AMCA specs of higher thrust Kaveri. Where is the lower thrust kaveri have gone operational? This may trigger a ramble, but the question itself can't be. :) This is a serious question (setting aside Pentaiah's Audrey Aftburn)?
Karan M
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Re: Kaveri & aero-engine discussion

Post by Karan M »

NRao, you are not alone. I find Pentaiah's constant references to his "knowledge", sarcastic remarks if anyone questions his statements & the constant rambling and disparaging of anything and everything Indian as a frightful bore and a total waste of time. One learns nothing apart from getting the feeling Shri Pentaiah is a know all (and the obligatory self deprecatory remarks which are not really self deprecatory are not a help). There were something like a dozen posts this gent made about how India was not good enough to make a light UAV engine or some such thing. Moment one flew, out came his comment that he could have done better with the budget etc. Just too much pomposity. In contrast, one can save posts like the ones Kartik and Maitya make.
I find it very hard to read/understand both, your and Sai's, posts. You guys tend to ramble. (Reminds me of the physics prof who started his class talking about surface on earth (topic of the lecture) .......... moved to air on earth. Atmosphere - made of troposphere, stratosphere, ......, ionosphere, ................... space, ................. no atmosphere on moon ......................... ended class with surface of moon.)
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Re: Kaveri & aero-engine discussion

Post by ramana »

NRAo, From what I understand there are two issues with Kaveri:
- It does not provide the thrust they need for the LCA
- It weighs more than the spec (~150Kg)


So bothare non-staters for the the second issue makes the first worse.

So all this SCB etc are to get more thrust while reducing weight.
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Re: Kaveri & aero-engine discussion

Post by NRao »

Ramana,

No issues. And, there could be plenty more "problems". BUT, my point is, a "problem" WRT to an engine especially is relative.

IF we were to say LCA-Kaveri, then absolutely, plenty of problems to id and track.

But, if we were to say a good engine - Kaveri is a good engine. Or, let me know what is wrong with it - as a stand alone engine.

As I stated, the only thing wrong with this entire picture is the expectations set ( a) that it will fly in 1996 (or whatever year) AND b) to mate it with the LCA). Take those two expectations away and let me know what the problem is.

However, on thrust for the LCA, it is my understanding the issue is with the wet thrust in particular, that the dry thrust is nearly there.

Weight, etc, yes, they are problems that engine faces. Forget such a complex project, my youngest rebuilt a 1991 Nissan 300ZX engine (yes, ground up) and he faced weight and other problems. (But that is the challenge we live for.)

To me the weight is a road bump. An expected one that too.

Heck and imagine when India overcomes that.

BTW, folks, the Kaveri was decoupled from the LCA some time back.

I still feel that both the LCA and the Kaveri should be tech demos.
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Re: Kaveri & aero-engine discussion

Post by SaiK »

I don't think we can write off a project like 'tech demos' no matter how you might feel strong on those lines, mr. rao. There could be technical disassociation from LCA, but from a management or finance perspective, we have committed huge -money and efforts to come to this level. There is no looking back on the use of Kaveri. If it does not fit LCA or LCA specs have changed, hence etc.. are still reasonable, but Kaveri has to find another reason like UCAV or some program to get into. It has to be operational to learn more and gather more data.

Kaveri-10 or next phase is needed, and it can't be delinked in any business sense.
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Re: Kaveri & aero-engine discussion

Post by shiv »

The Kaveri issue sounds like discussions I used to find on another forum where people were discussing air-rifles.

On that forum, there was not even one single detailed analysis of the actual performance of a single one of the 8 or 10 known brands of Indian air rifles. There was no comparison of even a single brand of Indian made pellets. 50% of forum threads were "How to import and air gun". When I dug deeper, I found that 90% of people were actually using Indian air guns and doing things to make them work and do the job they wanted - plinking or whatever. There was no analysis of what to do when exhorbitant imported air rifles went bust - as they all do over time. There was simply this continuous undercurrent of dissatisfaction about Indian stuff.

The point I want to make here is that we have to ask how we can use what we have rather than talk of how we would like to use what seems so attractive and available abroad.
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Re: Kaveri & aero-engine discussion

Post by Singha »

Flying the existing kaveri on tejas and proving its reliable operation is one line of work. That will prove the reliablity of materials and design , something which our panda brothers are really struggling with at present even if they have met the thrust goal to match their al31(nobody knows if they have)

Obviously we need the gromov style il76 flying testbed as well, plus gromov style ground test facilities if we are to design and build multiple new engines. Flying in a single engine fighter is only the last step and il76 is needed to test cruise missile, uav and ucav smaller engines as well. Goi should arrange to get one of the iaf il76 modified for this once the c17 starts to arrive.
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Re: Kaveri & aero-engine discussion

Post by Victor »

Kaveri is not "a" bad engine, it is just "the" bad engine for the LCA. It is actually OK compared to Rafale's M88 but its greater weight gives it a thrust/wt of .020 kN while the M88's is 25% higher at .025 kN. However, the Mig-27's Tumansky R29 also has a thrust/wt of .020 kN like Kaveri but is much bigger--16' vs 11'. The LCA is 43' long and the Mig-27 is 56' long. A twin-Kaveri powered aircraft of about 50' (the size of the Rafale) could theoretically have better performance than the Mig-27 and be a very useful and fully indigenous warplane.

Even now, a scaled up LCA could work out well without too much trouble and as Kaveri improves, so will this new aircraft. Dassault did something similar by scaling up the Mirage III fighter and ending up with the Mirage IV deep strike bomber.
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Re: Kaveri & aero-engine discussion

Post by shiv »

Singha wrote:Flying the existing kaveri on tejas and proving its reliable operation is one line of work. That will prove the reliablity of materials and design , something which our panda brothers are really struggling with at present even if they have met the thrust goal to match their al31(nobody knows if they have)

Obviously we need the gromov style il76 flying testbed as well, plus gromov style ground test facilities if we are to design and build multiple new engines. Flying in a single engine fighter is only the last step and il76 is needed to test cruise missile, uav and ucav smaller engines as well. Goi should arrange to get one of the iaf il76 modified for this once the c17 starts to arrive.
I think nothing will move until the DGCA has a total revamp in rules that allows the flights of experimental aircraft without stalling programs for 2, 3 4 years every time there is an incident. It is the DGCA rules in India that ensure that any minor accident leads to great delays and a single crash almost kills a program It is DGCA that is holding the Saras back

Contrast this with the speed and efficiency with which problems are handled in the US or even Australia where there is no DGCA like body that rules over research aircraft. The Mahindra collaboration with Australia worked really quick because of lack of Indian bureaucratic red tape.

Here is a post I had made earlier
shiv wrote:I got the link to the following enchanting video from a retired Air Marshal, no less, with the comment:
Amazing glider!Why can't we have something like this in our country? You cannot because DGCA inspectors will be breathing down your neck in no time !
http://player.vimeo.com/video/39325401
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Re: Kaveri & aero-engine discussion

Post by Singha »

>> Boeing will help us build hi-altitude test facility and a transonic wind tunnel in Hyderabad.

many are the promises of khan....let us see what comes of it. the location is the new huge defence campus in chitradurga in KA not Hyd. all of AEC, ADA, DRDO are supposed to have big scale campuses within it.
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Re: Kaveri & aero-engine discussion

Post by maitya »

Guys, I think we'll go nowhere if try to debate about Kaveri/Kabini as state-of-the-art or not, is it good or bad or is built from scratch or not?

As in most things in life, all of these attributes are relative and is thus pointless to label them as absolute, and argue based on it.
So, here’s my take (in 3 parts) on how this ab initio military turbojet/fan Engine development programme should be viewed/evaluated – apologies, it became a bit too long-winded (I have broken it up into 3 parts, for page-navigation ease).

Anyway here goes …

[Part 1]
Kaveri was technology-wise contemporary till late 90s - ok, maybe even early 2000s. Directionally Solidified Casted blades, Flat rating concept, near to 1400deg C TeT, 21-22 OPR etc are all hall marks of late 1990s military engines either being unveiled and in mass-use then.
So should we label it as contemporary engine, carte blanche - hell no!!

Contemporary (1990s) Engine R&D and it’s impact on Kaveri: The thing that happened is, while we were busy developing Kabini/Kaveri, the established engine developers were all into deep R&D and prototyping of the next gen technologies, broadly in the following areas:
1) Turbine Blade material technology - TET increase is one of the most important factors impacting efficiency levels of turbojet/turbofan. And herein the material and casting technology able to withstand additional 300deg C operating env - SCBs partly answers that problem, but TBCs, introduction of higher temp oxidation resistance properties and multi-flow air path within the blades are areas where huge progress was made.

2) Compressor Design - Some sort of a re-birth of this dormant R&D area happened in the 1990s, with surge in R&D (back to basics phenomena?) in the 90s, resulting in huge (some say game-changer) advancement seen in 2000s. Compressor design gains (and to an equally important aspect of the developing an industrial manufacturing capability to translate these design gains to actual manufactured products) direct have a bearing on Pressure Ratios, the other most critical parameter in a turbojet/turbofan.

The advent of supersonic compressor blade speed (1.6M - while Kaveri is stuck at transonic level of 1.2M etc), multi-circular blade design (kaveri, I think, is at best double-circular arc design), low-aspect ratio blade design and more importantly, the advances required in manufacturing engineering technology R&D (and subsequent manufacturing engineering capability) to be able to translate these designs into a high-strength and relatively high-temp compressor blades and disks, ensured that achievement of 2000s contemporary PR levels of 28-30.

So yes, the technology levels that we see in Kaveri/Kabini are what were already available in the military engines on 1980s and 1990s - i.e. these were in R&D and developed in 1970s and 1980s. We started the R&D and development in 1990s and two decades later (slightly more than what has been achieved by the western engine design houses in 1960-70s, maybe) we have close to a working engine.
But the engines available today (F414, for example) have already incorporated the technologies that were developed in 1990s and 2000s.

One pertinent question that comes up though (partially bought out by Pentaih-ji)?
All of the above reasoning is fine and maybe even acceptable - but couldn't we have shortened these 2 decades plus development and engineering period and somehow play catch-up.

The problem that I see in the previous set of posts is trying to argue that without any experience on turbojet and turbofan engine design capability, this is impossible to have been achieved. Well, experience is a huge factor but not the only factor – one of the major reasons for where we are today, IMVHO and daresay, are the design choices (both core engine design and material/manufacturing choices and design) being made back in 1980s.

But to understand this aspect we need to go back a bit and examine the history of Kaveri engine design/development.

[contd ...]
Last edited by maitya on 10 Apr 2013 00:28, edited 1 time in total.
maitya
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Re: Kaveri & aero-engine discussion

Post by maitya »

[Part 2]

Kaveri History: Well first-of-all, it’s erroneous to assume Kaveri (or GTX-35 VS) is the absolute first turbojet/turbofan to be designed/developed from the ground up (from scratch) by GTRE – it’s not. In fact Kaveri is not at all a “from the scratch” development in the first place – it more of an upgrade.

It’s predecessors were GTX-37 U (turbojet) -> GTX-37 UB (it’s turbofan version) -> GTX-35 (enhanced turbojet based on 37U tech). And Kaveri (or GTX-35 VS) is more of an upgrade of GTX-35 (same core etc.). The following schematic depicts the Kaveri lineage:

Image

Note: How the reduction of HPC stages were carried out to reduce weight, while increasing the turbine efficiency by increasing TET (and OPR) simultaneously – all of these required adavcnes in materials tech as well. Also note, the mass-flow drop during graduating from a turbojet to turbofan necessitating further efficiencies in turbine and compressor technologies (or increase in the number of corresponding stages).
Pls note the 37 series is from 70s and early 80s while the 35 series from late 80s to early-mid 90s.


But all of these, still doesn’t make the above “lack-of-experience” argument completely void – as none of these predecessors actually flew and are more of a laboratory products (or tech demos).
Back in 1983, right after the LCA project was sanctioned, a concurrent engine evaluation study was conducted by GTRE - in 2 years time, in 1985, this was completed and the summary finding was "No contemporary engine is available world-wide that meets the LCA engine specifications".

F-404 etc were after-thought and more importantly, risk mitigating steps, which due to non-delivery of the actual engine, has now become the default engine. :roll:

Anyway, similarly a “Materials Committee” of GTRE in 1989, after a comprehensive study of various materials of contemporary turbo-jet/fan engines, and also after taking into account the infrastructure facilities available within the country in general and production capability of MIDHANI and DMRL, recommended the development of material, batch production and type certification process etc.

The Kaveri development programme was then launched in 1989.

The Kaveri itself (actually only the core, kabini) first ran in Mar 1995 and 2 Kabini prototypes (C1 and C2) and 3 full engine prototypes (K1, K2 K3) ran between 1995 and 1998.
(contd ...)
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Re: Kaveri & aero-engine discussion

Post by maitya »

[Part 3]
Kaveri Design Choice Rational: With this historical background in place, IMVHO, I’d speculate that what really happened in 1990 or thereabouts, while the performance and (also materials roadmap) design for Kaveri were being finalized , is the designers and technologists of the GTRE were faced with a major dilemma:
  • 1) On the design front,
    • a. is it sensible to aim for the various core design parameters (e.g. OPR, TET, BPR, Combustor efficiency, supersonic compressor regimes, ultra-low aspect ratio blades, blisk manufacturing etc) of the various modern engine development programs in R&D
      OR
      b. to stick to the basic already understood basic design layouts of the GTX-37U and 37UBs and try and introduce medium-level of improvements on these design parameters and still meet the Kaveri specs.
    2) Similarly, on the materials front,
    • a. Aim of the materials technology being worked on at various material design houses (e.g 2nd and 3rd Gen SCBs, DS based later-stage compressor blades, 1st gen SCB based , Ceramic and Polymer Matrix based combustors and static-engine parts etc etc) and provide a quantum jump in performance parameters that was being asked from Kaveri specs
      OR
      b. Provide a more conservative incremental advancement in material tech (e.g. introduce Dir Solidified blades for HPT, Ti and Ni based-equiaxed-casted Compressor blades, contemporary “bolted” disk and blade interfaces, annular combustor etc) and still achieve the Kaveri specs
It may be fashionable to attribute the GTRE folks as failures/worthless/losers etc , but the fact they had a fair idea about the contemporary advancements being carried out world-wide, to have made the design-choices that were made, then.

So the decision matrix then may have looked like:

1(a)2(b) ---|--- 1(a)2(a)
---------- Risk ------------>
1(b)2(a) ---|--- 1(b)2(b)

The GTRE technologists and designers chose 4th quadrant i.e. 1(b)2(b) – of course, with a hidden/inner ambition of getting to the 1st quadrant stuff concurrently and as the general technological level of the country advances in next 2 decades.


Overall Design Goals met/not-met: Pls, one word of caution towards over-emphasizing the success of dry-thrust, 90% wet thrust achievement (SFC, well, not sure) etc – yes those values are achieved, but at what weight (and maybe SFC also) penalty?

If you look at the chart above, a prev gen GTX-37UB also would have met these figures, isn’t it (with even more weight and SFC penalty).

So IMO right way of labeling Kaveri is to call it as qualified-success. As it, for the first time, if pursued with no let-up thru the flight-test-programme, will validate a flying turbofan engine – in technological terms it would
1) validate (and provide invaluable empirical data) the CFD and basic mechanical design of a twin-spool 80KN turbofan (90s level)
2) given enough design and manufacturing technological confidence of 80s level of material tech

Without these there’s no hope of leapfrogging technological gens etc (refer to epilogue section for a glimpse of that), and we're doomed to play catch-up forever.


Inference: But there-in lies the problem,
i.e. first, recall the findings of Engine evaluation study of 1985 which basically stated LCA engine specs are set high-enough to be met by a contemporary engine then. Now contrast that with the constraining technological choices (aka Conservative-Conservative) being made for Kaveri to achieve those.

This essentially means, there’s wafer-thin margin of error towards meeting both the core engine-design parameters and the enabling material/manufacturing design/technology. Even shortfall of one parameter may spell doom – and that’s precisely happened with Kaveri albeit shortfall in meeting almost all design parameters (admittedly, by small enough margin but big enough to all contribute to a compounding effect of the shortfall we see today).

But wait, before we start dishing out our advises, from our hindsight-is-20/20 vantage point, let’s try and think thru why would the GTRE folks not consider high-high risk of 1(a)2(a) approach.

Well, if you look at our national psyche of extremely naval-gazing, if-it’s-made-in-India-must-be-useless, pricing-of-tech-dev-in-terms-of-social-upliftment-missed-cost, 3-legged-cheetah-labelling-user-attitude etc. (Shivji will have a longer list), GTRE folks would be mortally scared of failures arising from such a high-risk endeavor.
Frankly, I’m not very sure if it mattered to the GTRE folks, if LCA flew or not, as long as they have met the Kaveri design parameters. So when the larger program, due to scope creep, necessitated a requirement growth of a next-gen powerplant, Kaveri in it’s present technological form is not even close to it.

Plus all this talk of new imported core etc means exactly that – a fully imported engine in terms of jet-engine tech, nothing more nothing else. :roll:

That’s the price to be paid for a pessimistic/stifling national outlook towards technological advancement with zero-tolerance towards failures and import at all cost attitude. :(


Epilogue: While we constantly continue to berate the GTRE folks for technological failure etc, a small bit of snippet needs understanding.

In mid-2000s, desperate to trying to reduce the overweight Kaveri (it’s still overweight by 150Kg or there-abouts), GTRE folks went ahead experimenting with the absolute cutting edge of material tech i.e. Ceramic Matrix Composites (CMC) and Polymer Matrix Composites (PMC) on some of the non-rotating-non-critical components. CMC was targeted towards a few hot-components like Nozzle divergent petals, exhaust cone etc – while PMC (high temp PMR-15 class) towards bypass duct, CD Nozzle cowls at the back etc.

The aim was to reduce weight by 30Kgs (i.e. approx. 20-25%).

In contrast, pls google around for CMC and PMC related R&D and, more importantly, it’s usage on various aero-engine by established western players (Hint: some links are there couple of pages back on this very thread).

This confidence and attitude are the true by-products of the Kaveri engine development program.
[The End]
Avarachan
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Re: Kaveri & aero-engine discussion

Post by Avarachan »

Maitya, thank you for these very informative posts.

I have a question for you. Given that the Kaveri is to be used in IUSAV (the unmanned strike platform), do you think that the conservative design choice was the right one? After all, because GTRE went with the conservative choice, at least India will soon have an engine it can use for other purposes, apart from the Tejas.
Surya
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Re: Kaveri & aero-engine discussion

Post by Surya »

thanks Maitya

please print it and also mail it to Philip saar :P
suryag
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Re: Kaveri & aero-engine discussion

Post by suryag »

Thanks Maitya ji for giving some gyan to this armchair chaprasi
Sancho
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Re: Kaveri & aero-engine discussion

Post by Sancho »

maitya wrote: Frankly, I’m not very sure if it mattered to the GTRE folks, if LCA flew or not, as long as they have met the Kaveri design parameters. So when the larger program, due to scope creep, necessitated a requirement growth of a next-gen powerplant, Kaveri in it’s present technological form is not even close to it.

First of all, thank you for this very interesting and detailed report, but I think this quoted part explains why Kaveri today ended up as a failure, because it was directly aimed on LCA, which in return made LCA dependent on a successful Kaveri development!
That indeed left very low space for failures, but has nothing to do with an import at all cost attitude, like you concluded, but with the major planing failure to develop both projects independently, by choosing a foreign engine for the prototypes and the first serial produced versions (LCA MK1). That would have made the Kaveri project de-linked of LCA from the start, with the option to integrate it, as soon as it offers the required performance and maturity, while not risking anything with the LCA project as a whole. IF there would have been this attitude that you mentioned, we would have done it as I explained (and as it is basically done all over the world), which would at least made the fighter project to a success today, but sadly we didn't and ran both projects into a big mess.

If Kaveri on the other side would have been seen as a separate, tech demonstrator project, you would have been right to say, that it is at least a partial success, since some of the project goals were achieved. Not to mention that in terms of experience, it was a very valuable project to set up the baseline for fighter engine developments in India.
Based on this tech demo engine, we could have either developed production versions for LCA (if the requirements would have been met), or could have used it as the base for further advanced developments. But again, we didn't used a procedure that is usual all over the world, to gain experience and know how, but wanted to achieve everything alone and directly at the first attempt.
As a result of these own failures, we had to go for foreign consultancy partners, for numerous re-designs, for later licence productions when we had no other choice anymore, or to consider a Kaveri engine with a foreign core, because ours was not useful for the platform we planned it for. And the end of the story is basically where it should have started from, de-linked from LCA with the search for an experienced partner for a co-development!
srai
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Re: Kaveri & aero-engine discussion

Post by srai »

^^^

Almost always, when a new combat plane is designed it also requires a new (or modified) engine to meet its specific performance specification. No one builds fighter jet engine independent of a fighter aircraft. Engine dimensions, weight, fuel consumption, etc. are specified by the host aircraft design.
pentaiah
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Re: Kaveri & aero-engine discussion

Post by pentaiah »

Ok so when do we get Kaveri for a basic trainer or some a/c to say we have indian engine in this plane and simple lets settle for some thing that lifts a air frame with out being on IL or Tu or Su etc

My nightmare is
LCA will end up as HF24 Redux ,

Excellent aircraft Top notch design, ........????
Pratyush
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Re: Kaveri & aero-engine discussion

Post by Pratyush »

^^^

I am more concerned with the LCA meeting the same fate as the Arjun.
vic
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Re: Kaveri & aero-engine discussion

Post by vic »

Basic engine technology remains useful for 60-70 years with evolutionary upgrades.
GeorgeM
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Re: Kaveri & aero-engine discussion

Post by GeorgeM »

Sancho wrote: First of all, thank you for this very interesting and detailed report, but I think this quoted part explains why Kaveri today ended up as a failure, because it was directly aimed on LCA, which in return made LCA dependent on a successful Kaveri development!
Sancho.. I am impressed.. pura ramayan padne ke baad.. yeh sala Ravan Sita ki kaun..
Where does he say Kaveri is a failure. Have you worked in technologically dense large NPI projects with every one in the world trying to cut you down. You say delink LCA from Kaveri, but then in the time frame LCA was finalized, we were driving American companies out of India. It was CIA all over the news. We had a very strong desire to develop things in-house.
That indeed left very low space for failures, ...

Like what... It is very easy to criticize with 20/20 hindsight. When you work on a high pressure program even with the seemingly friendly collaborators you have immense difficulty in delivering on time, within cost, with desired quality. I work for a company with 90 yrs experience in designing/manufacturing large diesel engines. But even today with Euro norms, Tier4, 5000 ppm sulfur, etc, we still have difficulty meeting all the above targets. We have PhD's, Universities, FEV, Ricardo, AVL, SWRI and then US GoI funding etc at our disposal. Talk about GTRE and funded by GoI babus. GTRE have done a tremendous job and you need to stop your armchair criticism
That would have made the Kaveri project de-linked of LCA from the start,..

Please refer to srai's comment on this. Engine is the heart of any project - aero, missiles, rockets etc. And you want to develop aircraft independent of engines. Last I smoked something this potent was in Idukki mountains. Please quote examples.
(and as it is basically done all over the world)...
Like where, when ?
which would at least made the fighter project to a success today, but sadly we didn't and ran both projects into a big mess....
Oh since when did LCA too become 'not a success today'. We have developed a whole lot a capabilities on top of developing a fighter - materials, manufacturing, certification, tools, control systems, software tools, testing methods, scientists, MGPP, etc.. what makes you think LCA is not a success.
No I am not here to pick a fight. I am here to get an education. Be humble, be open minded. Be willing to appreciate what tremendous hard work others are putting in. Dont jump to the trigger like bunch of guys on ToI comments section. This is BR, you will get your ars** handed back in a platter.
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