Kaveri & Aero-Engine: News & Discussion

The Military Issues & History Forum is a venue to discuss issues relating to the military aspects of the Indian Armed Forces, whether the past, present or future. We request members to kindly stay within the mandate of this forum and keep their exchanges of views, on a civilised level, however vehemently any disagreement may be felt. All feedback regarding forum usage may be sent to the moderators using the Feedback Form or by clicking the Report Post Icon in any objectionable post for proper action. Please note that the views expressed by the Members and Moderators on these discussion boards are that of the individuals only and do not reflect the official policy or view of the Bharat-Rakshak.com Website. Copyright Violation is strictly prohibited and may result in revocation of your posting rights - please read the FAQ for full details. Users must also abide by the Forum Guidelines at all times.
Post Reply
maitya
BR Mainsite Crew
Posts: 622
Joined: 02 Feb 2001 12:31

Re: Kaveri & aero-engine discussion

Post by maitya »

Avarachan wrote: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.
Avarachanji, reg the conservative engine technology roadmap for Kaveri, selected by the GTRE folks, well, let me put it this way.

There's simply no other choice - 2nd (1a-2b) and 3rd (1b-2a) quadrant choices couldn't have been taken, as in the late 80s (when this decision was being taken) the status of,

1) Prevalent Materials R&D and, more importantly, indigenously available manufacturing and engineering base to translate these designs to manufactured parts/products etc.
AND
2) Low experience on the mechanical and CFD (from non-flying testbeds like GTX-37U and UB etc.) aspects of an aero-engine design

To give a short example of 1)
How many times here in BR we have heard that if only we could have mastered Blisk-manufacturing technology, most (if not all) issues of Kaveri would be sorted. What never gets discussed or thought thru is what it really means in terms of constraints that are being tried to overcome.
I'll not go into too much detail (will reserve that for Material write-up, if it ever gets finished :(( - most likely it won't, just like my engine-design related write-ups - all lying around at 50-60% completion level :oops:), let me try to bring out a small dichotomy (in context of blisk manufacturing usage).

Let's look at a HPT stage of a Turbine - now the blades will be required to withstand 1600-1700deg C temp and tip-rotor speed of about 1.5M. But what about the disk - the temp there seldom will reach beyond 800-900 deg C and speed maybe 0.9M.

Big difference, isn't it? But that's not all.
Look at the picture of an military turbojet/fan HPT, for example that of a F-110 as shown below:

Image

Now if you compare the mass of the disk and that of the blades, it's obvious that the mass of disk is many order-of-magnitude more than that of the blades.
So between the disk and the blades of the same HPT stage, you have the following:
  • Factors ----------------- Disk ------------- Blade
    -----------------------------------------------------
    Operating Temp -------- 1700degC -------- 850degC
    Speed -------------------- 1.5M ------------ 0.9M
    Mass -------------------- easily 10-12 times of Blades (cumulative)
    Cycle Fatigue ----------- Low ------------ High
(will explain this in a later post)

So the mechanical pressure due to good-old centrifugal force on a disk is multiple times more than that of the blades - but the operating temp regime is also very different.

So for the disk you would ideally be looking for some material with very good tensile ductility, high tensile yield and ultimate strength (and LCF too - more on this on some other day) - while the temp operating environment gives you a lot of leeway (compared to blades), so much so you can get away with even equiaxed-casted materials.
But for the blades the requirements are high Thermal Mechanical Fatigue (TMF) resistance (aka higher melting points), Creep-rupture strength and HCF - while lot of leeway on mechanical strength aspects like tensile yield/strength and ductility.

So for the blades you are constrained to have casted materials that have directionally oriented grains parallel to airfoil axis (aka DS or SC) - but that's not all, due to high-temp operating env, it needs to have a good ability to accept TBC as well (plus higher oxidation resistance properties - again more on this on a later day). But the operating word is "casted" alloys.

And there-in lies the problem.

As casted alloys generally have lower tensile properties, worser ductility and lesser homogeneity making them unsuitable for a disk application - to have those kinds of mechanical properties you need wrought alloys.

So, coming back to the topic of blisk manufacturing etc - you are basically asking/looking for an "integral" manufacturing process where the disk part is made of wrought superalloy, while the blade part being from casted superalloy.

This should give us an idea about what challenging the material/manufacturing R&D and engineering aspect could be.

I'll later bring out a suitable example from 2 as well.

But coming back to your original point about design choices - this above example, would be sufficient to demonstrate that how many options the GTRE folks would have had then, given our experience on integral casting etc, to reject the possibility of blisked turbine stage development route. Instead, it would have been less riskier to have accepted the then prevalent bolted-blades-on-disk philosophy and live with the resultant compromise on the TeT itself. And that's what the GTRE folks did.

Pls note the above example is not some "virtual" one - something quite similar actually happened with Kaveri where-in the in-house developed HPT disk had to be rejected (when the TeT was increased, as the blades were found to be able to accept a few tens of degrees C more TeT) and import (from USA) the HPT disks (while the HPT blades remained indigenous DS ones). But that story for another day. :mrgreen:
Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

Re: Kaveri & aero-engine discussion

Post by Singha »

in blisks, if the material of disk and blade is to be different as per above, then how is the blisk machined out of a single round "disc" of metal?
is this disc itself in molten state somehow made to have a central core of material1 and a annular region of material2?
Neela
BRF Oldie
Posts: 4102
Joined: 30 Jul 2004 15:05
Location: Spectator in the dossier diplomacy tennis match

Re: Kaveri & aero-engine discussion

Post by Neela »

Firstly, maitya , many thanks for this.
Been following your posts but I will find time sometime in the next weeks to read it up.

Singha wrote:in blisks, if the material of disk and blade is to be different as per above, then how is the blisk machined out of a single round "disc" of metal?
is this disc itself in molten state somehow made to have a central core of material1 and a annular region of material2?
Singha,
Excellent question. I have seen videos of turbine blades created from single piece as well as separately.
What you are referring to ( I think ) is here:



But the above video's title could be wrong ; could above be a compressor stage ?


Here the SC blades are manufactured separately. Please see from 25:20 min onwards .( It starts with " It is a closely guarded secret" )
Starts with hand crafted models -> finish.




If both are turbine stages , then the difference could possibly be the purpose ( commercial vs military)
shaardula
BRF Oldie
Posts: 2591
Joined: 17 Apr 2006 20:02

Re: Kaveri & aero-engine discussion

Post by shaardula »

pentaiah wrote: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
test
SaiK
BRF Oldie
Posts: 36424
Joined: 29 Oct 2003 12:31
Location: NowHere

Re: Kaveri & aero-engine discussion

Post by SaiK »

for a reduced weight, for the non TET but near TET areas, CMC materials can withstand upto 1200*C. example: X-38. exhausts, plates, vents etc can look towards this material. In addition to blisk tech, and directional solidified materials, other surface coating technologies and blade venting technologies have been proven by rolls royce - especially the micro holes on the SC blades, in the direction of air flow. they have brought down the temp quit a bit with that approach.

However, advanced CMC is the way to go even for the TET areas, where GE is proving things stable at 2400*C. GE90-115B the most powerful one in the world !!
http://www.youtube.com/watch?v=666VH25FeG0
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

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?
So my guess work was right. HTFE-25 is the name of a 25 kN turbofan engine being developed by HAL's AERDC. From HAL-Connect- Issue 65
AERDC is seen to have very large business potential since there are no other major players in the country working on Aero-engine development. Currently, it is working on small gas turbine engine i.e. JFS, APU etc development and 25KN medium thrust turbofan engine. Significant requirement of Jet Fuel Starter (JFS) for Su-30MKI and Hawk is forecast. The R&D center gradually intends to take up development of 1200 KW shaft engine development for helicopter, civil variant of the 25 KN engine and 2MW power class engine besides developing engine test beds for various types of engines.
Sancho
BRFite
Posts: 152
Joined: 18 Nov 2010 21:03
Location: Germany

Re: Kaveri & aero-engine discussion

Post by Sancho »

Sidharth wrote: Where does he say Kaveri is a failure.
He doesn't, I said it explains why it ended it a failure, because GTRE according to him had only the development of the engine in mind, not that the specs meet with the requirement of LCA. The outcome was an engine that might work and in certain specific configs offers the required thrust on paper, but does not fit to the requirements of the fighter and since Kaveri was developed specifically with certain goals for LCA, which it didn't met, it is a failure today.
Sidharth wrote: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.
The first part is just the usual excuse that I hear all the time, by ignoring the fact that we had years in between the start of the project and this, that we could have used in a better way, with the licence production of a foreign engine from the start, or forming a joint development. Just like the fact that we had other countries that could have offered us engines or partnerships, back than than the US only. In Fact the same countries that still offers us techs or co-developments (Russia and France).
The second part is the sad truth, we followed our desires and not any rational thinking, with the aim to make the fighter a success, in the best way according to our capabilities. If that would have been the case, we would have gone for foreign stopgap engines and radars, acknowledging that we didn't had enough expertise to do it ALL alone. So focusing on the things we can do, would have been the right way to secure a smooth development of the fighter, while starting indigenous core tech developments separately!
Sidharth wrote:GTRE have done a tremendous job and you need to stop your armchair criticism
Pointing out the mistakes that were done is not wrong, but aims on understanding them to not do the same again. What you do instead is simply denying the fact that we have developed an engine, for that we have no application for in the current form and that this is one of the main reasons why the LCA program (which is the more important indigenous program), is in such a mess today! Not to mention that there are a lot of IAF or IN officials that said the same, that ADA/DRDO often promised things, that they couldn't do.

Sidharth wrote:Oh since when did LCA too become 'not a success today'.
Because we develop the fighter for decades now, but still have only prototypes flying around, without a serial production or a single fighter inducted in our forces!
An before you reply...
If your company would work on a new engine for the same time, but wouldn't get it ready and into production for any vehicle, would you call the engine a success? Of course not, even if you might have learned the one or the other thing on the way, you didn't have a final product that your company can use / sell.

There is no doubt that both a extremely important projects for India and that we had to go for both developments, but we should have done them in a way better way, with a more rational point of view of our technical capabilities and less blinded by indigenous pride!
PratikDas
BRFite
Posts: 1927
Joined: 06 Feb 2009 07:46
Contact:

Re: Kaveri & aero-engine discussion

Post by PratikDas »

I love how people keep thrashing the indigenous pride strawman because it conveniently but disingenuously helps in making the point, when indigenous intellectual property is really what this is all about. It is no secret that the theft of German patents after WWI and even more so after WWII helped the US immensely post-war. Project after project has shown that the lack of theoretical and process knowledge has hindered military R&D in India.

There cannot be any let up on the development of Indian intellectual property. Sure, the whole infrastructure and management organisation can be revamped.

On a side note, I've been noticing for a while, probably like others on BRF, that India's alleged need for pride is the only reason for any significant achievement:

Agni V: The sad MAD world of Agni-V by Venky Vembu, FirstPost
Yet, the irony of nuclear weapons – and of delivery mechanisms like Agni V – is that having acquired them and bolstered our pride (and our deterrent capability), we now have to pray that we’ll never ever have to use them. That’s because the moment for which they are being primed for use will always be too late. And even that moment will give us no pride or joy.
Other countries do it for deterrence but India supposedly does it for pride onlee.

Indian economy: Why India is not a superpower, Amrit Dhillon for London School of Propaganda Economics via SMH
Yet should anyone plead that the poor have been left behind they will be subject to heated criticism. It hurts the pride of Indians to be reminded of the country's poverty. But the existence of poverty itself does not hurt their pride.
Widening poverty gap seems to be a problem affecting many countries, including the EU and the US but when it comes to India the subject of derision seems to be Indian "pride", not the global issue of a widening poverty gap itself.

1998 Nuclear Tests: NUCLEAR ANXIETY: IN INDIA; New Delhi Premier Indicates Resolve to Produce Nuclear Weapons, John F Burns, New York Times
Mr. Vajpayee confirmed the role that national pride played in the decision to carry out the tests. His Bharatiya Janata Party, or Indian People's Party, leads a movement that has worked for 70 years to persuade Indians that an assertive Hindu pride is the solution to India's problems. That stance has alarmed India's minority of 120 million Muslims, as well as Pakistan, a Muslim state created out of the partition of British India in 1947.

''India has never considered military might as the ultimate measure of national strength,'' Mr. Vajpayee said. ''It is a necessary component of overall national strength. I would, therefore, say that the greatest meaning of the tests is they have given India shakti, they have given India strength, they have given India self-confidence.'' Shakti is a Hindi word meaning power, commonly used when referring to Hindu gods.
So many layers of bullshit here. Where to begin?

The Indian PM says "self-confidence". The author chooses to hear not just "pride" but "Hindu pride". Once you've had to a chance to get over that, read about the author's hallucination of an "alarmed" minority of 120 million Muslims, like all 120 Indian Muslims were shocked that India had nuclear weapons.

Vajpayee ji says "strength". The author hears the name of "Hindu gods".

Chandrayaan: Fly Me to the Deity, Tunku Varadarajan, Professor of Business at New York University, Op-Ed at Forbes.com, via New York Times
The Hindu astrological system is predicated on lunar movements: so the moon is a big deal in astrology-obsessed India. That said, the genius of modern Hinduism lies in its comfort with, and imperviousness to, science. A friend tells me of an episode from his childhood in Varanasi, the sacred Hindu city. Days after Apollo 11 landed on the moon, a model of the lunar module was placed in a courtyard of the most venerable temple in the city. The Hindu faithful were hailing man-on-the-moon; there was no suggestion that the Americans had committed sacrilege. (Here, I might add — with a caveat against exaggeration — that science sometimes struggles to co-exist with faith in the United States in ways that would disconcert many Indians.)

Of course, the Chandrayaan is also a grand political gesture — space exploration in the service of national pride. This kind of excursion may provoke yawns at NASA, but judging from round-the-clock local coverage it has received, the mission has clearly inflamed the imagination and ambition of Indians. Yes, even moon-worshipping ones.
Only in December 2012, after Neil Armstrong passed away in August, 43 years after the lunar landing was it revealed that he practiced that famous line, "one small step for man...". Oh really? Like the paced delivery of every word of that sentence didn't seem staged in the first place, but that wasn't going to diminish the huge achievement of going to the moon, was it? Not for me, anyway. With Chandrayaan though, just one week after PSLV took off on 22 October 2008 and before Chandrayaan reached the moon in November, you already have a professor of business opining about customary day long fasts by Hindu women, astrology-obsessed India, political gestures and national pride. On the one hand the author goes on to opine that Hinduism is impervious to science and on the other hand the monumental scientific milestone of sending a probe to the moon misses him completely.

India in the UN Security Council: India's Tough Road to the Security Council, Raja Menon for the Atlantic Council, yes - another Menon :mrgreen:, yes the same "Council" that wants India to demilitarize Siachen
The Indian army has stayed clear of politics—period. The phenomenon of Ike or Colin Powell (and maybe once Petraeus), born of Americans’ periodic hopes that a military-hero-turned-politician will lead them toward splendid vistas, is unknown in India. When Indian generals retire, they’re expected to play tennis or golf and dote over their grandchildren, a scotch in hand. Field Marshal Sam Manekshaw, architect of India’s victory over Pakistan in the 1971 war and arguably India’s most charismatic military chieftain, retired two years later, settling in a bucolic town in the South India’s lush Nilgiri Hills. That’s the Indian pattern of civil-military relations.

This democratic record is impressive, even more so given India’s lack of the typical preconditions. (And no, it’s not thanks to the British legacy: consider the histories of Pakistan, Nigeria, Burma and Zimbabwe, to name but a few of Her Majesty’s former domains). Call this India’s legitimacy argument for a Security Council seat.

So this explains India’s yearning for the Security Council. You’ll get other arguments in New Delhi—better global governance and so on. But it’s really about stuff that’s a lot less concrete: pride, recognition and entitlement.
Countries like UK, France and China have no reason at all for being part of the Security Council after WWII considering the first two would be speaking German today had it not been for the US and the third one got thrashed by Japan. India's democracy record is noted as an irrelevant side note. India's seat in the UNSC somehow requires a "legitimacy argument" when 3 out of 5 members had none to begin with. After all, India has no need for a seat at the UNSC apart from a "yearning" for "pride, recognition and entitlement", right?

When I see people disregarding the genuine need for Indian national development programs, however dysfunctional their track records might appear, alleging pride as India's motivator and disingenuously ignoring the genuine need for national security in Siachen for example, deterrence with nuclear weapons and ICBMs, intellectual property via military R&D programs, rights to natural resources - be it in the Indian Ocean region, in the Antarctic, on the Moon, or on Mars, they lose credibility fast, at least in my eyes.
maitya
BR Mainsite Crew
Posts: 622
Joined: 02 Feb 2001 12:31

Re: Kaveri & aero-engine discussion

Post by maitya »

Sancho wrote:
Sidharth wrote: Where does he say Kaveri is a failure.
He doesn't, I said it explains why it ended it a failure, because GTRE according to him had only the development of the engine in mind, not that the specs meet with the requirement of LCA. The outcome was an engine that might work and in certain specific configs offers the required thrust on paper, but does not fit to the requirements of the fighter and since Kaveri was developed specifically with certain goals for LCA, which it didn't met, it is a failure today.
Sancho, not exactly sure what you are trying to say.

Nowhere in the world billions of $s are spent in developing a science project, as you are alluding to, without clear-cut and exact specifications in place. And, for a turbojet/turbofan development programs, the dimensional and the performance parameters are absolutely vital on deciding which way program would go.

So just like any other turbojet/turbofan program, Kaveri also had it's performance (Th - 52/80KN, SFC - 80/207 kg/kN.h, TWR - 76N/Kg) parameters define to be achieved within the specified dimensional constraints (of L - 3.5m, D - 0.9m and Wt - 950Kg). Those performance and dimensional parameters are around which the LCA airframe dimension, strength and overall design (e.g. air-intake design) itself were specified.

PS: Also as I've pointed out in my previous post, these parameters were not only contemporary but actually world-beaters in those days - recall, how when the Kaveri design/performance-parameter-specifying-committee tried to look for another existing (or being on the verge of being put into use) military turbofan to cross-validate and baseline Kaveri’s parametric-model against what they’d have actually achieved (as opposed to copy-paste from some shiny brochures), they couldn't find any.
This should also put to rest, any notion of modesty/reticence towards the sheer technological scale this program intended to leap-frog – some may rightly say, that we aimed too high.


So anyway, if Kaveri would have met these specified parameters it would have been good enough for the LCA.

And which it almost did - except for the weight and wet thrust part, where it fell short by 10-15% - for which it can be labeled as failure etc, and GTRE folks needs to re-double their effort to regain back those shortfalls.
As after all, theoretically (for the sake of argument) if it were to be argued that Thrust is the be-all and end-all and dimensional constraints are not important, then Kaveri program itself hardly required - those thrust ratios were achieved almost a decade back by it's predecessors (GTX-37 UB tec.)

On the contrary, dimensional parameters are extremely important as it would limit the mass-flow rate, number of compressor (and even turbine) stages that can be squeezed-in, the BPR itself etc - all having direct impact on the performance parameters like Thrust, Weight, SFC etc
(PS: a couple of pages back, I've posted a very very simplified-excel-based turbojet "designing" tool 8) - you may try and play around those 3 simple parameters and do some cause-effect kind of analysis).

But that's hardly the point.

The point that I's trying to make above was - the design choices/technological roadmap chosen (due to a various of factors discussed above) in developing Kaveri. That conservative approach meant, while the program (and these design choices) were sufficient to meet Kaveri performance specs, it provided almost nil cushion against any performance parameter scope-creep.
So when LCA got overweight by 1.2tons or so (it was originally envisaged to be a 5.5-ton class fighter), the Kaveri core couldn't provide any easy scaling-up capability of the performance parameters required to address this scope-creep. But, how can the GTRE folks be directly faulted for not able to address this scope-creep etc - they didn't have any contribution towards LCAs weight-gain, after all.

Even then, mind-you theoretically, even-now if the mass-flow can be increased, this Kaveri core can have enhanced Thrust rating as well - but all other performance parameters like SFC etc will suffer big time - due to a further reduction in Thermal Efficiency (refer ot that excel, a couple of pages back). So, such kind of stunts are always avoided.

So is there any +ves of this program - Yes, and actually there are too many to count - but all of these +ve can be very easily bought to naught, if Kaveri program is abandoned at this and not taken to it's logical conclusion of completing a comprehensive flight-test program.
With this program, we have for the first time understood and will continue to understand the FD, Mechanical design and material/manufacturing technological/engineering aspects of 80KN class twin-spool turbofan engine (this is as cutting edge as it ever gets), as the next stages of the program are undertaken - something that has taken more than half-of-century by the industrialized world to master, and no nation will ever pass-on that knowledge, however friendly they are to us.

For example (just to make a point), the SPR of a HPC stage can be dramatically improved by carefully "introducing well-shaped" intra-stage shock waves (where is N^3, when you need him most).
And given the OPR achieved so far in Kaveri is about 21 or thereabouts (against a design goal of 27), this can be a very tempting option. But who is going to tell us the blade strength, blade geometry, aspect ratio, solidity etc which helps in initiating, sustaining and optimizing it. And even if they do, who is going to tell us the material composition and physical characteristics of these HPC stage blades that will be required to achieve it - nobody, I repeat, absolutely nobody. We will have to try, fail, try again, fail again, try again and learn it the hard way.

There’s absolutely no other way.
pentaiah
BRFite
Posts: 1671
Joined: 11 Aug 2016 06:14

Re: Kaveri & aero-engine discussion

Post by pentaiah »

If you wanted world beating specked engine you must have the infrastructure , engineering and metallurgical capabilities in place. We did not have everything we required to develop world beating engine, and then we coupled it to development of 4 th generation aircraft frame and avionics

All this while the last know aircraft of indigenous content was 1950s late to mid 1960 effort of HF. 24

And ironically that also did not full fill expectation for want of engine.....

All this now sounds like sending a Hindi medium student never exposed to more than English alphabet to compete in scrips Howard spelling beer completion and win the first prize too.

Now imagine after producing 30
LCA GE says sorry cant supply any more as SD placed sanctions...
If the current events of conventional arms export restrictions come into place and engines are classified as export restricted item....?

That's why ML Jaisimha the captain of Hyderabad used to say Mien payla gola Ko roko badmein chavva rokneka socho and he ranjitorphy ....
NRao
BRF Oldie
Posts: 19226
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: Kaveri & aero-engine discussion

Post by NRao »

That is one way to look at it - they should have built world class facilities before embarking on .......

Or that they, with inadequate facilities, on no fault of their own, fell short by around 20% on wet thrust and some 150 kgs shy on weight.

I would have liked for them to have done it in a much shorter time. But heck I am thrilled with what they have achieved given what they had.
Austin
BRF Oldie
Posts: 23387
Joined: 23 Jul 2000 11:31

Re: Kaveri & aero-engine discussion

Post by Austin »

I am not aware if Kaveri test was sucessful the last time it flew on IL-76 platform but it was then they should quickly build 1-2 prototypes around kaveri engine and flight test the engine.

These test would be similar to what we did with F-404 or planning to do with F-414/Mk2 and would involve the entire flight envelop and in different weather condition ...this is going to be long and the most challenging phase for Kaveri engine program.

As pentaiah has mentioned if GE Engines get sanctioned the entire LCA program would collapse without having an alternative engine , With Kaveri worked out in parallel it would assure the Tejas program continues even if it means having a lower performance due to a weaker engine but that is still better and we can improve Kaveri at a later stage.
SaiK
BRF Oldie
Posts: 36424
Joined: 29 Oct 2003 12:31
Location: NowHere

Re: Kaveri & aero-engine discussion

Post by SaiK »

see, the point of irritation is not with GTRE taking time to do, or GTRE didn't achieve by 15% etc.. The point is stopping the continuation of engineering dead stop, and asking for international support to finish the 15% or asking for help. This is unacceptable. Neither will international developers will reveal or help on our terms to enhance nor we will be successful with that approach.

Get back to basics, put the engine we have on LCA TD, and keep testing it., while charter on the next stage of development plans for the higher thrust and t:w requirements. Don't ask help externally except to MoD budget for test facilities and support. Ask GTRE to stop behaving childish.. they have already spent and come this far, and we have full kudos and support for them. They can get reorged, or do whatever it takes to get it done.. and this time better done to full spec needs.
neerajb
BRFite
Posts: 853
Joined: 24 Jun 2008 14:18
Location: Delhi, India.

Re: Kaveri & aero-engine discussion

Post by neerajb »

I remember last time we were discussing why electric start is not used in gas turbine engines. This is why.

[youtube]6pdAdLiV-GA&list=PLE5I9ZZNPu1MyWiZ8qhESxQxESVJ41YgG&index=7[/youtube]

Cheers....
pentaiah
BRFite
Posts: 1671
Joined: 11 Aug 2016 06:14

Re: Kaveri & aero-engine discussion

Post by pentaiah »

MiG 21 uses electric starters to start up the turbine
. For MiG 21
Starting is electrical by means of a starter/ generator and is controlled by a single push button. Initial light-up is done using petrol from an auxiliary tank.

Silver Zinc Batteries

HBL makes silver zinc chemistry based aircraft battery for MiG series, Kamov helicopter, etc.
Silver zinc batteries offer one of the highest energy density + advantage of compact design.
To make your business competitive, these batteries can be offered with or without containers.
Furthermore, HBL offers a one-to-one replacement in nickel chemistry for the same application to help match your budget.
HBL Silver Zinc Aircraft batteries are currently in use in various aircraft in India and overseas.

http://www.hbl.in/Aircraft_Silver%20Zinc.asp
hanumadu
BRF Oldie
Posts: 5168
Joined: 11 Nov 2002 12:31

Re: Kaveri & aero-engine discussion

Post by hanumadu »

NRao wrote:That is one way to look at it - they should have built world class facilities before embarking on .......
Except that to set up world class facilities itself, we need world class technology which we currently do not possess.
We need Boeing to set up a wind tunnel for us.
Boeing to help set up transonic tunnel facility

The way I see it is, we need an all round advance in all spheres of technology before we can start developing great products with regularity. But to get to such a stage, we must continue to invest in Indian R&D and see projects to the end however long it takes. We will not come to possess advanced technology by giving up.
hanumadu
BRF Oldie
Posts: 5168
Joined: 11 Nov 2002 12:31

Re: Kaveri & aero-engine discussion

Post by hanumadu »

It is better to aim high and fall short than create something that is easy to achieve but of not much use. Atleast, we now know what we lack in the various technologies that go into developing a Kaveri. Even though Kaveri did not meet its expectations yet, I think GTRE will find it much easier to develop alternate versions that are not so ambitious if there is such a need. But as far as Kaveri goes, we have no choice but stick with the task of developing our own jet engine that can power Tejas.
pentaiah
BRFite
Posts: 1671
Joined: 11 Aug 2016 06:14

Re: Kaveri & aero-engine discussion

Post by pentaiah »

I wonder what IIT Kharagpur aeronautical guys ever do? make rubber band planes as practical projects?

I guess B tech Aeronautical guys must be selling white goods for lever brothers or Procter and gamble
( their careers in aeronautical no way)

Osmania university has wind tunnel and as well as gas turbine but it was gathering cobwebs in 1970s

No body operated them no professor was interested in doing anything with it.

Shame that 60 yrs and yet we hear no contribution from them, atl least Kalam was from Madras institute of technology a diploma in Aeronautics after BSc
pentaiah
BRFite
Posts: 1671
Joined: 11 Aug 2016 06:14

Re: Kaveri & aero-engine discussion

Post by pentaiah »

hanumadu wrote:It is better to aim high and fall short than create something that is easy to achieve but of not much use. Atleast, we now know what we lack in the various technologies that go into developing a Kaveri. Even though Kaveri did not meet its expectations yet, I think GTRE will find it much easier to develop alternate versions that are not so ambitious if there is such a need. But as far as Kaveri goes, we have no choice but stick with the task of developing our own jet engine that can power Tejas.

Yes yes we should have gone for neutron bum and single stage solid fuel underwater missile instead of liquid fuel Prithvi, then Liquid fuel Agni
symontk
BRFite
Posts: 920
Joined: 01 Nov 2001 12:31
Location: Bangalore

Re: Kaveri & aero-engine discussion

Post by symontk »

What will happen if GE stops producing the version we are using after say 10 years. Don't we need a new engine then? Or do we have an agreement that they will keep producing this until we have LCA

How does it work with other aircrafts? Do the airforce keep spare engines that long a time? Since the airframe has definite life its doable, but just asking if anyone knows this
Austin
BRF Oldie
Posts: 23387
Joined: 23 Jul 2000 11:31

Re: Kaveri & aero-engine discussion

Post by Austin »

From the Airforce officer talk at AI , it seems if an OEM decides to shut shop or stop making xyz product then it informs the customer in advance and then the end user has to stock spares ,tools etc for the entire life time of the aircraft.
Prem Kumar
BRF Oldie
Posts: 4218
Joined: 31 Mar 2009 00:10

Re: Kaveri & aero-engine discussion

Post by Prem Kumar »

Am X-posting this in multiple threads. The following is a scathing criticism of Jugaad and our lack of engineering/design focus as a nation. Read and weep.

This article especially makes sense in the Kaveri thread. N^3 would appreciate the point about how some engineers think CAD becomes a "lazy substitute" for real design knowledge. He used to have similar laments about CFD software.

http://www.ipfonline.com/IPFCONTENT/art ... ndia-1.php
vic
BRF Oldie
Posts: 2412
Joined: 19 May 2010 10:00

Re: Kaveri & aero-engine discussion

Post by vic »

indranilroy wrote:
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?
So my guess work was right. HTFE-25 is the name of a 25 kN turbofan engine being developed by HAL's AERDC. From HAL-Connect- Issue 65
AERDC is seen to have very large business potential since there are no other major players in the country working on Aero-engine development. Currently, it is working on small gas turbine engine i.e. JFS, APU etc development and 25KN medium thrust turbofan engine. Significant requirement of Jet Fuel Starter (JFS) for Su-30MKI and Hawk is forecast. The R&D center gradually intends to take up development of 1200 KW shaft engine development for helicopter, civil variant of the 25 KN engine and 2MW power class engine besides developing engine test beds for various types of engines.

It is a very important development which we have missed. It seems that HAL is developing upgraded indigenised versions of Shakti engine from 1000kw to 1200kw and upgraded Al-55 engine from 17kn to 25kn. I hope HAL also launches programme to upgrade Garrett engine as we have no turboprop engine in our stable and such engines will be required for UCAVs and Basic Trainers.
SaiK
BRF Oldie
Posts: 36424
Joined: 29 Oct 2003 12:31
Location: NowHere

Re: Kaveri & aero-engine discussion

Post by SaiK »

There is only way out for forward thinking.. instead of asking HAL to do everything, under the aegis of DRDO, whatever production quality product comes out of r&d is spawned into a new reality - no matter what type - gov, quasi-gov, or private-public partnership. gov has to take leadership role, especially drdo now, because it is lame to keep beating the dead lion. of course, there are certain areas HAL excels, that experience must be turned into a transferable reality in the new firm.. as we do this, we separate the screw tech HAL to re-engineered concurrently advanced HAL. call it whatever, HAL-2 or new HAL or BAL, but don't carry forward the screw driver learning forward, rather keep it at sub assembly level.

we have to delink r&d and production, but make it a collaborative entities rather cohesive one under one umbrella. HAL is a big management issue for the country.
VKumar
BRFite
Posts: 730
Joined: 15 Sep 1999 11:31
Location: Mumbai,India

Re: Kaveri & aero-engine discussion

Post by VKumar »

Can the Kaveri be fitted on the LCA? If so, it may be worthwhile to take a TD and try out in incremental steps.
Austin
BRF Oldie
Posts: 23387
Joined: 23 Jul 2000 11:31

Re: Kaveri & aero-engine discussion

Post by Austin »

VKumar wrote:Can the Kaveri be fitted on the LCA? If so, it may be worthwhile to take a TD and try out in incremental steps.
Ofcourse , LCA was built around Kaveri and ADA has mentioned that they would use TD to test Kaveri once its ready.

I just hope they dont just test it on one TD but build one squadron around it , it would do a lot good to build future engines
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

vic wrote: It is a very important development which we have missed. It seems that HAL is developing upgraded indigenised versions of Shakti engine from 1000kw to 1200kw and upgraded Al-55 engine from 17kn to 25kn. I hope HAL also launches programme to upgrade Garrett engine as we have no turboprop engine in our stable and such engines will be required for UCAVs and Basic Trainers.
Actually I think the 1200 KW engine is actually the Ardiden 1U engine for LUH. It is the further development of Shakti and is supposedly 15% more powerful than Shakti. However, AFAIK the development is being done by Turbomeca. I don't know what HAL would be doing other than license production. I would be very happy to know if HAL is developing its competitor to Ardiden 1U.

The 2000KW is certainly the engine for the IMRH. Will it be a Ardiden 3? Don't know.

I don't know whether HAL's 25 kN engine is an upgraded AI-55. Somehow my gut feeling is that it is their in-house project. I have seen tenders for their parts which looked like ab-initio work. Could be wrong. What is important is that HAL said that first it wants to develop the engine first for UAVs, and then modify it for civilian use. So, now the door is open for IUSAV to use Kaveri or HTFE-25. From the diagrams of IUSAV carrying only 2 LGBs, it certainly does not need a 45 kN engine. So are there multiple IUSAVs?

HAL is developing a turboprop engine as well. Click
Future Programs :
• Small Turbofan Engine for UAVs
• APU for MTA
• Starter Engine for Fighter Aircraft Engines
• Turboprop engine for Trainer Aircraft
• Gas Turbine Engine for Industrial Application-4 MW Class
vic
BRF Oldie
Posts: 2412
Joined: 19 May 2010 10:00

Re: Kaveri & aero-engine discussion

Post by vic »

Where did u get 2000kw engine bit?
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

vic wrote:Where did u get 2000kw engine bit?
indranilroy wrote: From HAL-Connect- Issue 65
AERDC is seen to have very large business potential since there are no other major players in the country working on Aero-engine development. Currently, it is working on small gas turbine engine i.e. JFS, APU etc development and 25KN medium thrust turbofan engine. Significant requirement of Jet Fuel Starter (JFS) for Su-30MKI and Hawk is forecast. The R&D center gradually intends to take up development of 1200 KW shaft engine development for helicopter, civil variant of the 25 KN engine and 2MW power class engine besides developing engine test beds for various types of engines.
vic
BRF Oldie
Posts: 2412
Joined: 19 May 2010 10:00

Re: Kaveri & aero-engine discussion

Post by vic »

Reading all these news together :-

HAL wanted to develop a turboprop engine but there is no more news on that front except tender for import of engines of Basic Trainer. Preferably HAL should develop an upgraded version of Garrett which it is already manufacturing, which can be used for Reaper variant of Rustom.

1200 kw seems HAL development from the language and not Turbomeca product. But hopefully it is an upgrade of Shakti and not a ab initio product.

25kn engine seems like a Civil variant, what? hopefully again is upgrade of AL-55 engine rather than ab initio product which would take a very long time. I suppose we can use such engine for Global Hawk variant of Rustom-xx

2MW power class seems like industrial engine or generator, why are you calling it a turbo shaft?
Austin
BRF Oldie
Posts: 23387
Joined: 23 Jul 2000 11:31

Re: Kaveri & aero-engine discussion

Post by Austin »

Any news of Kaveri suceeding for Naval Platforms , I am aware of the fact that they were testing it for naval application but dont recollect any of the newer ships moving to use it in production batches.
vic
BRF Oldie
Posts: 2412
Joined: 19 May 2010 10:00

Re: Kaveri & aero-engine discussion

Post by vic »

If HAL increases the use of composites in HTT-40 then perhaps we can use Garrett which HAL is already manufacturing.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

vic wrote: HAL wanted to develop a turboprop engine but there is no more news on that front except tender for import of engines of Basic Trainer. Preferably HAL should develop an upgraded version of Garrett which it is already manufacturing, which can be used for Reaper variant of Rustom.
Obviously HAL can't wait for its own turboprop engine for HTT-40. That plane needs to fly and fly fast. The intended use of HAL's turboprop engine is for trainers too.
vic wrote: 1200 kw seems HAL development from the language and not Turbomeca product. But hopefully it is an upgrade of Shakti and not a ab initio product.
Looking at their immediate engine requirement for LUH, I think it is the Ardiden 1U. Just an educated guess. We will see.
vic wrote: 25kn engine seems like a Civil variant, what? hopefully again is upgrade of AL-55 engine rather than ab initio product which would take a very long time. I suppose we can use such engine for Global Hawk variant of Rustom-xx
No they are developing the engine for UAVs first. Then they will certify it for civilian planes (like business jets).
vic wrote:2MW power class seems like industrial engine or generator, why are you calling it a turbo shaft?
Hunch :-).
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

vic wrote:If HAL increases the use of composites in HTT-40 then perhaps we can use Garrett which HAL is already manufacturing.
HAL has categorically told that it is an all metal plane. I don't think they will invest in developing yet another plane with yet another engine. We can expect composite parts if empty weight comes up higher than designed.
vic
BRF Oldie
Posts: 2412
Joined: 19 May 2010 10:00

Re: Kaveri & aero-engine discussion

Post by vic »

IIRC Garrett version made by HAL is 715hp, now PC-7 Mark-2 seems to have PT6 700hp engine which has effective delivered power compared to Garrett around 15% less, so HAL Garrett is 715hp and PC-7 Mark-2 engine is effectively 600hp. Now why does HAL ignore it's own engine and comes with import requirement of slightly more powerful engine then Garrett rather than tweaking the airframe and using Garret?

Remember a similar interesting situation, Army wanted an imported gun between 31mm to 39mm shell size, as Reinmetal was supplying bribes to promote 35mm revolver gun and Army wanted to kill indigenous 30mm and 40mm options.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

The PC-7 MarkII
MTOW: 2250 kg
Power: 700 hp

HTT-40
MTOW: 2800 kg
Power: 945 hp

There are 2 options for HAL. Either develop the composites, or make the plane fly by mid-2015. Their choice is obvious to me.
Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

Re: Kaveri & aero-engine discussion

Post by Singha »

at all costs, promises by maker of developing a 'new' +20% EPE variant of existing engine must be avoided. we need something that is in FOCed service today with the desired thrust level. else its game over.
SaiK
BRF Oldie
Posts: 36424
Joined: 29 Oct 2003 12:31
Location: NowHere

Re: Kaveri & aero-engine discussion

Post by SaiK »

well said, whatever F414 98kN should suffice for LCA Mk2.. The IN version should be all about documents, and how to integrate more with FADEC rather.

Kaveri should chase after the higher thrust.. again an achievement of near 100kN is royal good for the current requirement.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Kaveri & aero-engine discussion

Post by Indranil »

^^^ AFAIK, Singhaji is speaking of +20% EPE version figuratively. He means choose an established engine for HTT-40 from day 1.
maitya
BR Mainsite Crew
Posts: 622
Joined: 02 Feb 2001 12:31

Re: Kaveri & aero-engine discussion

Post by maitya »

X-posting from the FGFA thread ...
maitya wrote:
JTull wrote: ...
As far as engines are concerned, we've all known how inadequate efforts towards Kaveri have been and but I was sick of watching everyone after AI-13, being busy back-slapping over some single-crystal blades that aren't of requisite caliber to be used. More years are being wasted at GTRE in coming up products from yesteryears (and being completely clueless in the process), while the world is pursuing and achieving next generation technologies. We're only good for a begging bowl, hoping one of the other engine makers will just give us the required tech by way of consulting contract.
...
JTullji, while this angst is somewhat justified vis-à-vis Kaveri (and GTRE), the bolded part above (about them being "products from yesteryears" and "completely clueless" etc) is not true.

Since discussing about Kaveri/GTRE et all is completely OT for this thread, I'd request you to consider taking the discussion to the Kaveri thread - for starters pls refer to this post (actually a 3 part-series of posts) of moi on Perspective of Kaveri Dev Failure/Success - IMO a better and more balanced perspective is required while dissecting teh Kaveri development process (there are series of posts in that thread, both before and after that post-series, which delves into this aspect).

And to start the ball rolling, let me make very bold stmt - it doesn't matter what gen etc of the technology is being pursued as long as the desired objective is met - and one can only aim for a tech gen provided a baseline level of the required capability and experience is available.

As far as Kaveri is concerned, a contrarian view can be, we aimed too high a tech gen (given the technological baseline and engineering capability - both on gas-turbine CFD and material tech) with Kaveri and failed in achieving it by a whisker. An ab-intio F-404 gen (so, the 3rd Gen Turbojet – maybe 1st Gen military Turbofan) is just too high to aim for given the indigenous turbojet/turbofan technological and material engineering capability that we possess.

But we’d start somewhere, isn’t it? And any ab-intio tech dev is inherently as-risky-as-it-ever-gets and Kaveri is no exception.
And it’s always better to aim higher and take-on the long and painful grind then to just go for what is available (or import) and maybe make good press out of it – a rhetorical question can be, would IAF ever accepted a GTX-37UB level engine (so required Thrust achieved but very poor SFC and weight) for LCA ?

Moreover, like all technological advancements, the next Gen of technology is more achieved by incremental advances over the previous Gen technological levels. For example, you will notice that the 4th Gen F414 level (aka F414-EPE or F414-GE-INS6 for LCA Mk-II), are based on 3rd Gen F404 tech. Similarly, on the material technology front, notice the diff between 3rd (CMX-4) and 4th Gen (CMX-10) SCBs (except for Re composition increase, and the corresponding balancing of other heavy elements of the alloy, not much of difference between the two gens) – some details of which can be found here.

So, IMVHO, if we pursue Kaveri devt program to it's logical conclusion of full-range-of-FTB tests etc, we'd have mastered the 3rd Gen Turbojet (maybe 1st Gen military Turbofan) technology end-to-end. Based on which the 4th Gen engine etc development can be taken up.


And regarding your point about "back-slapping over some single-crystal blades that aren't of requisite caliber to be used" - well, that's a huge improvement on it's own, as basically until this years' AI, we were not even sure if we are able to manufacture any SCBs (forget about 2nd, 3rd, 4th Gen SCB etc) in the first place.

Pls refer to this talk by GTRE director, T. Mohan Rao, in AI09 here – notice, how he points out the basic future thrust areas that need working on … and I quote,
a. BLISK - integrated single Blade and Disk
b. Single Crystal blades - he categorically said - We do not have that tech at all.
c. Thermal Barrier Coatings - TBC - very critical for high temp engine operation.
That was back in 2009 and in 2013, we have a photo of an indigenously developed SCB blade - yes, we don’t know yet which gen it is, and what kind of thermal fatigue, creep resistance and mechanical pressure it can withstand – but isn’t that a huge progress, even if we conservatively assume it to be 2nd Gen SCB etc.

Admins and fellow posters, apologies for this completely OT post for this thread, but I thought it’s relevant in the context of JTullji’s post above.
Post Reply