Kaveri & Aero-Engine: News & Discussion

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Re: Kaveri & aero-engine discussion

Postby Neela » 16 Jan 2014 17:28

^^^^
From Siemens.
This from a someone working in BHEL.

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Re: Kaveri & aero-engine discussion

Postby JTull » 16 Jan 2014 17:47

Neela wrote:^^^^
From Siemens.
This from a someone working in BHEL.


Until few years ago, BHEL was still importing all turbine blades for the turbines it manufactured. It might be different story now.

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Re: Kaveri & aero-engine discussion

Postby vic » 16 Jan 2014 21:05

I always thought BHEL is another screw driver wielder but somebody on BRF was claiming that they were spending few hundred crores per annum for R&D

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Re: Kaveri & aero-engine discussion

Postby SaiK » 17 Jan 2014 03:22

For validating technologies, R&D does mostly need full scale model. Existing Kaveri baseline is excellent live model to improve on. R&D should happen more on the existing product line, rather pure r&d just to prove one aspect of a design or need. When one puts all the bits and pieces, the overall core engine is considered as a unit for LCA. So, unless it happens as a whole, bits and pieces achievement is only a stepping stone, and not a milestone.

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Re: Kaveri & aero-engine discussion

Postby member_22019 » 18 Jan 2014 12:13

Sir, I had a question in my mind since long. Don't know if it is right to ask it here, but still requesting, if some guru can please explain in layman's term.
Is the engine of a modern fighter aircraft is the toughest part to develop in comparison to other defense components? Is it even more complex than GSLV? I mean, why ISRO is able to overcome all the challenges and ultimately develops GSLV, but Kaveri is still incomplete. My intention is not to undermine GTRE efforts, I am just trying to know the real problem with Kaveri development.

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Re: Kaveri & aero-engine discussion

Postby member_22539 » 18 Jan 2014 17:29

^Not an expert, but from what I understand the Jet engine of the fighter jet is indeed the toughest part to develop at the level of state-of-the-art and cutting edge. Even radar and avionics pale in comparison.

As for ISRO and its engines/launch vehicles, they are in the end a strategic asset and even if they are a little less efficient or technologically behind what the Euros and US has, it really does not matter. The strategic benefits and the cost benefits are just too much to make such minor inefficiencies matter. A launch vehicle that has a smaller payload will just launch a smaller satellite, but to have a fighter-bomber with a limited payload may mean losing the tactical advantage. After-all, one pertains to winning wars defending the nation and one to space exploration/exploitation (which matters in the long run, but one can take some time with it).

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Re: Kaveri & aero-engine discussion

Postby maitya » 18 Jan 2014 21:43

== post deleted ==
Last edited by maitya on 18 Jan 2014 22:59, edited 1 time in total.

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 18 Jan 2014 22:56

On See Eff Dee, I am in deep depression onlee. According to me, India is the ideal place for See Eff Dee: no shortage of hungry math-adept students (maybe I am wrong?) and even greater oversupply of Eye-Tee whizzes. What more could one ask? YET... all I see going on is beebals using (ef)FLUENT or other canned codes, with no clue of what is inside them. These bloody things are just big notepads to invert matrices and solve finite difference equations, hey? How tough is that to program, liberally copying from Schlichting, Hermanullah Khan's kitabs?

Commercial see eff dee codes are GIGO, and I make that fatwa with total authority and hard experience. BUT.. one can develop one's OWN See Eff Dee code, and put in one's OWN fudge factors and match known results very well. The difference is small but important: here you KNOW where you are cheating.

I think for turbomachine development, good See Eff Dee is a must, to get beyond 1-D Station Analysis and 2-D Cascade etc. Rotational effects are first-order, and no one has a real clue about the development of lift and drag on a swept, curved, cambered, twisted low aspect ratio blade with transonic high temperature flow. So who in India is working on that is my pooch.

And to get the blood flowing, I will state my other fatwa based on 30-year frustration: I think engineering professors in Indian universities are, with few exceptions, plumb lazy. Underpaid for their positions, but way overpaid for their actual work ethic anbd productivity. This is why India is unable to develop good engines, or good anything where true world-beating innovation is needed. Obviously in politics and music people are more hungry, hence we have world-beating naxalites and playback singers.

Point is, if you start work on a REALLY FAR-OUT concept today, you won't face any ITAR or anything, because no one has thought to mark that technology or believes it will work. Then you get far enough ahead with papers etc. and then you are not subject to ITAR etc because they are trying to steal from you, nothing gained by refusing to sell to you. This simple fatwa has proved impossible to drum into the cranial cavities of Indian profs. It's always:
Eej NAJA doing this onlee?
as criterion for whether they should exert to get off their musharrafs. Sorry, OT, but back to the P&W pooch...

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 18 Jan 2014 23:07

For instance, we recently found out that by simply making the surface of a blade rough, one could vastly increase the output of a centrifugal blower stage. Rotational effect: it has the same effect as increasing the viscosity of the fluid very close to the blade, thereby generating much more radial acceleration. You would never get this without true 3D, rotating analysis, none of this Cascade Theory or Blade Element Theory stuff!

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Re: Kaveri & aero-engine discussion

Postby sivab » 18 Jan 2014 23:29

N^3? Welcome back.

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Re: Kaveri & aero-engine discussion

Postby Sagar G » 18 Jan 2014 23:33

GTRE has developed some CFD codes on it's own and also uses the one's available commercially.

Welcome back saar :twisted:

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Re: Kaveri & aero-engine discussion

Postby SaiK » 19 Jan 2014 03:59

Yes the blade design can largely impact the compression and flow.. there are data available from rolls royce and cfm to this effect.

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Re: Kaveri & aero-engine discussion

Postby SaiK » 22 Jan 2014 10:09

Did they gave a date/quarter for porting to Mig-29 this year?

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Re: Kaveri & aero-engine discussion

Postby SaiK » 23 Jan 2014 19:07

apologies admin: I don't want to post in the kaveri saga thread this question [constructive thinking onlee]
aam pooch reg counter rotating high bypass: would not high bypass counter the t:w ratio owing to reduced mass flow through the compression chamber?

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 23 Jan 2014 20:35

Why would mass flow be reduced? I (have not thought of that, and so) see no reason. The counter-rotating stages just eliminate the swirl put into the flow by each stage, without needing stator/guide vanes. Conceptually, that is. IMO this may reduce the "solidity" needed to keep the flow attached over the stator vanes, so it should in fact increase the mass flow through the passage (IOW reduce the diameter needed to get a given bypass). Can't see why this would not be good for hi-bypass, I think the old GE Unducted Aft Fan concept (1980s/90s b4 it was killed by falling oil prices and rising noise about engine noise) just extended the counter-rotating turbine stages into fan blades, and that is a huge bypass ratio.

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Re: Kaveri & aero-engine discussion

Postby SaiK » 24 Jan 2014 04:48

saab ji, i think my pooch was muffled with multitasking.. it was about why it should not be low bypass and counter-rotating. well let me ask another one.. does counter-rotation and bypass ratio have any relationship w.r.t thrust? any tradeoff?.

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 24 Jan 2014 06:20

I don't think so. AFAIK, counter-rotating is just a strategy to reduce the weight of the turbomachine, and maybe reduce the number of stages by half. Bypass ratio is usually driven by the aircraft's mission profile, and by other messy decisions like frontal area available, etc. Very basic parameter that affects the efficiency.

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Re: Kaveri & aero-engine discussion

Postby srin » 24 Jan 2014 14:01

UBji, can you please describe (in the Kaveri saga thread if you prefer) the flat-rating of the Kaveri and how that compares to other engines, that presumably aren't ?

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 24 Jan 2014 17:59

Sorry I have no idea what "flat rating" means. I have seen the term in statements put out by the Kaveri mgmt, but took them to be more political than technical.

Most engines have thrust decreasing as altitude increases, at constant Mach number. IOW, you can get hajaar karod thrust while standing still, but at 15,000 meters there may be a lot less thrust. To first approximation, thrust is proportional to 1/(density), meaning less air coming in, less thrust. Things are much worse on Hot Day, and worse on Hot Day Above Himalayas (you think you are at 20,000 m going by the low density, but then you ask:
What is Brinjez Ayesha doing way up in this cloudbank? Heading to Houristan?


I don't know of any magic around this. Super-charged IC engines claimed "flat power" all the way to 7000 meters, presumably by pumping up the air going into the cylinders, but I don't know how to do this on turbofan engines unless one has some exotic variable geometry. Or, of course, one can simply have less thrust at the low altitudes to achieve "flat thrust" spec. :roll:

The thrust also decreases with forward speed, for subsonic flight. See above why "static sea-level" thrust is the most wonderful.
However, turbojet engines actually have thrust increasing with Mach number, beyond Mach 1. May reach max at Mach 2 or so and then drop off fast. This is because of some interplay between shock pressure recovery (so the injun thinks it is at sea-level), propulsive efficiency working best when the exhaust speed is closer to flight speed, and shock losses. One has to run the 1-D analysis at least, to see this curve: It looks like houri lying on side with knees curled (I mean as in horizontal attitude, not level of truth-telling). The max height of curve may not be at shoulder but at musharraf.

Fighter injuns have low bypass (like 1 or so), so their curve may be fairly close to that of a pure turbojet. So did the Kaveri ppl figure out some way to level this curve out? Maybe. Did it make the thrust higher in the tummy/spare tyre part, or lower in the shoulder and musharraf? I have no idea.

Somehow I don't believe that the Kaveri injun delivers the same thrust at Mach 1.4, 15,000 m, as it does standing still at COK on a cold morning.

In short, I am 404 on this. :((

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Re: Kaveri & aero-engine discussion

Postby SaiK » 24 Jan 2014 19:14

on the weight reduction, i agree there needs to be ton of work to be done.. materialistically and structurally, i can visualize the huge weight gain by redesigning the blades [focus on more blade space, increased flow, and reduced disk space]. this can be taken up along with other strategies identified and experienced [counter rotating, extendable spool, ..].

caveats also needs to be highlighted on these, where it can impede our folks so that the stakeholders are well aware of risks in such ventures... of course taking the risk is all about inventing and re-inventing [which i like because invention only once, does not validate the invention at all].

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 24 Jan 2014 19:33

So many opportunities, so few GTRE DOOs. Practice to-date seems to be the only one practical for such a small team: downselect long before one has any hope of seeing what might succeed, follow one design, and as one gets stuck on each aspect, look around for phoren collaborashun to get beyond that. The whole design becomes obsolete long before one can get to the end. Which is why the other thread was set up - there need to be hajaar-hajaar concepts being explored and tested, and competing to be put on testbeds. Guvrmand facilities like GTRE should focus on enabling testbed operation and validation and outsource the basic innovation to many sources.

As one reference point, does GTRE have as many employees as the Yoo Ess Embassy in Dilli? They have > 1000.

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Re: Kaveri & aero-engine discussion

Postby SaiK » 24 Jan 2014 20:04

^+108 + move the r&d to private space or private funded space, and GTRE has the main collaborators, program managers, integrators and regulators, process gurus, and v&v guys [focus to enable r&d within a secured zone, nothing more political about it].

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 24 Jan 2014 21:37

IMO, "R&D" and "private-funded" are incompatible when it comes to national-level needs with long getation times. Esp. desi "privates". Which is why it has to be centrally-funded, university-based, with lots of PIGS.

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Re: Kaveri & aero-engine discussion

Postby SaiK » 24 Jan 2014 22:37

then, they have to zone it like mumbai SEPZ (not exactly), but specifically within DRDO/GTRE workspace. that will give the privates into consulting/contracting mode, while centrally-funded, edu-based PIGS could be the drivers.

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Re: Kaveri & aero-engine discussion

Postby UlanBatori » 25 Jan 2014 00:50

We can discuss on the academic thread, but I am not a fan of these SEZs etc - they invariably lead to something with the word "scam" at the end. The question I have is whether there are any examples of real, basic and applied RESEARCH advances made in Indian ENGINEERING over the past many years by private enterprise, i.e., outside of the defense and nuclear domains. I know TIFR was well-reputed, but did not last as a well-reputed org for many decades. Gone now from public view, AFAIK. Hindustan Motors of Ambassador fame? Reliance? Tata/Birla? Mahindra? Larsen-Toubro? Kirloskar? Please think on the other thread.
This is my basis for being pessimistic about Indian engg. R&D coming out of private enterprise. Opening this door in Defense research will be just like Kabir ke dohe as paraphrased by IIT denizens:
jisko jitna chahiye,
kaat-kaat le jayiye

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Re: Kaveri & aero-engine discussion

Postby SaiK » 25 Jan 2014 07:11

regarding your post on the saga thread on 3-d printing etc.. pooch:

does DRDO has any 3-d printing facility?

not sure how one would do, if the chosen material say polymer/ceramic matrix composites? even the 25% scaled version should use what would possible get into 100% one... again, only if r&d on scaled models are in the plan. this is an excellent direction for DRDO to do for establishing tech, v&v requirements, etc.. it could also end up as biproducts for niche UAVs, UCAVs, or even specially designed dedicated TVC engines just for pitch, yaw and roll controls onlee.

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Re: Kaveri & aero-engine discussion

Postby Neshant » 25 Jan 2014 10:28

SaiK wrote:Did they gave a date/quarter for porting to Mig-29 this year?


I hope Russia is on board with this program.

It might revive the global fortunes of the Mig-29 and its derivatives.

Aside from India, Mig has not had a sale in years.

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Re: Kaveri & aero-engine discussion

Postby SaiK » 27 Jan 2014 00:47

The failure of the Kaveri project is just one of many examples of how the Indian defense procurement bureaucracy misfires. Efforts to fix the mess even led to calling in foreign experts (from the U.S., Israel, and other Western nations). For example, in 2010 India made arrangements with French engine manufacturer Snecma to provide technical assistance for the Kaveri design and manufacturing problems. Critics in the Indian air force asserted that help from Snecma would not save the ill-fated Kaveri program. But the government apparently believed that it was necessary for India to acquire the ability to design and build world class jet engines, whatever the cost. Only a few nations can do this and India wants to be one of them, soon, no matter what obstacles are encountered. Despite decades of effort, the Kaveri never quite made it to mass production. Now the government will continue funding development of jet engine design and manufacturing capability, but with some unspecified changes.

anything unspecified is fraught with risks, caveats and fraud. sorry, should this article reflect any truth.

http://www.strategypage.com/htmw/htmurp ... 31228.aspx

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Re: Kaveri & aero-engine discussion

Postby vina » 27 Jan 2014 04:45

UB wrote:Somehow I don't believe that the Kaveri injun delivers the same thrust at Mach 1.4, 15,000 m, as it does standing still at COK on a cold morning.

If I read all the Babu /desi Inglees put by the GTRE folks, all this phlat-rating bijness seems to be simply that the injin is derated from full power (static power at ISA) with sufficient temp margins at turbine inlet to give guaranteed thrust of 78KN at ISA +15/+20 (whatever).

Desi babus want to do away with marketing sharketing. So, like YechYeaYell saying YellCeeYea can go only upto Vellore from Bengaluru and come back, and SU-30 can go only up to Chennai from Bangalore Kerala and come back, which is actually the truth, while the Rodina folks will claim that SU30 can fly all the way to Singapore from Bangalore and come back, our marketing shorn folks want to say, that in May in Bangalore , Kerala, this jehaaj can take off from the YechYeaYell runway, without needing help from the earth's curvature to take off!

So my sympathies are with the folks who give the truth as it is and not put out ishpin like "My Yinjin generates 980000000000000 KN in Al Kaneda, AoA , AK Phyrr!!! (but if you read phine-e-brint, that translates in Kannada to only 78KN in Bangalore, Kerala)

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Re: Kaveri & aero-engine discussion

Postby vic » 28 Jan 2014 19:18

It seems that slowly we are revving up for engine R&D across the Board. I thought I will re-make a list:-

Ground Vehicles

1500-1800hp tank engine (What about transmission?)
500-600hp ground vehicle engine with transmission

Airborne platforms

10hp, 20hp, 40hp UAV piston engines
55hp wankel engine for UAV
110-127-xx kw Jet starters for LCA Mark-1, 2, FGFA
xx kw APU for MRTA
4kn turbojet PTAE-7 by HAL
4kn turbofan by HAL, NAL, GTRE (for cruise missiles and UAV)
1200kw turboshaft by HAL (This is 1600hp turboshaft engine. If 1200kw is assumed to be continuous maximum power output then this engine (and will be used of IMRH) is around twice the power of SHAKTI engine which has continuous max power output of 900hp. Max 30 min output of such engine can be say 2000-2200hp and max take off 2200-2400hp or emergency output upto 2400-2800hp. Note Mi-17’s engine latest engine is VK-2500 and has continuous power rating of only 1100kw, so this engine would be intended for a heavier or more powerful engine. The point is whether this engine is off shoot of Shakti or ab initio design.
20-30kn for IJT, AJT, Civil Liner (UAV?) etc by HAL (HAL has allocated Rs 400 crores for it)
50/80kn Kaveri Gas turbine engine and Non afterburning version for UCAV for which GTRE had asked for Rs 500 crore but no info in open source about further progress
75/110kn +5% uprating potential, a new Gas turbine engine (RFPs out for LP stage) This engine seems to be 130kn engine which has been referred for AMCA, as 110kn engine may have war/emergency setting of upto 130kn.

Marine Engine

10000-16000hp based on Kaveri
1.2MW ship based Generator based on Kaveri
Battery pack and thermal engines for light and heavy torpedoes
Battery packs for subs
Fuels Cells for subs
Nuclear Reactor 100MW for subs
Diesel – Pielstick JV of kirloskars

Industrial

4MW based on Kaveri

Mini and Micro UAV
Electric engines
Space Based

Solid fueled 9tons, 139tons, 200tons etc (used in SLV, ASLV, PSLV, GSLV)
Cryo 7.5kn, 20kn
PAM-upper stage
Semi Cryo 2000Kn
Rumored

Airborne platforms

150hp diesel UAV piston engines
250-500hp turboprop engine for UAV
Turboprop by HAL for Trainer

Space Based
Cryo 60kn, 100kn

Railway
CNG engine based on Kaveri

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Re: Kaveri & aero-engine discussion

Postby Will » 18 Feb 2014 14:15

Is anything even happening on the Kaveri? We should just forget about even starting on the AMCA till we have a decently matured engine.

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Re: Kaveri & aero-engine discussion

Postby NRao » 01 Mar 2014 03:50


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Re: Kaveri & aero-engine discussion

Postby gnair » 01 Mar 2014 04:14

The article mentions 'billion' dollars in a couple of places, that may not be accurate. It should be million instead.

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Re: Kaveri & aero-engine discussion

Postby maitya » 01 Mar 2014 15:02

NRao wrote:A long article:

An 'engine' for India's growth
...
...
Given the specifications of the AMCA a much higher thrust engine than the designed output of the Kaveri will be required for the AMCA even though it is envisioned as a twin engine aircraft. Accordingly, tender documents show that GTRE's next turbofan is in the 110 KN wet and 75 KN dry thrust category. An engine of this capability will certainly require GTRE to master single crystal blade(SCB) technology, integrated rotor disk and blades and super alloys of nickel and cobalt. The Kaveri currently uses directionally solidified blade technology and neither that nor even first generation SCBs which can now be fashioned in India will suffice for the new engine.
...
...

Good article and quite a few data points - covers quite a bit of ground from a lay-man turbofan technology etc also. Also confirmation of 75KN dry thrust Kaveri-II is in the works.

However, some important points need further detailing (as it's too high-level):

1) Wrt SCB - yes, 3rd gen SCB (where Ru gets introduced and Re % gets capped at around 5-6%) is the need of the hour, no doubt. But that's not what will automatically get the required high TeT numbers (of say 1650-1700deg C), that one would expect from an contemporary military turbofan.

Pls note Thrust can be up-scaled (to a certain degree) by increasing mass flow.
Problem with that kind of a solution is that the Thermal efficiency (and Propulsive efficiency as well) will go for a toss. And to maintain balance between an increased Thrust and the thermal (and propulsive) efficiencies, both TeT and OPR needs enhancement to a large degree.

And that's exactly where-in lies the catch.

A 3rd Gen SCB, on it's own will give a max 70-90deg C upscaling of TeT (pls note 2nd Gen ones gives around 30-40deg C max upscaling). From a DS-based Kabini/Kaveri TeT of ~1455deg C that takes one to not even to 1550deg C TeT, well short of 1650-1700 deg C that one would desire from an contemporary turbofan.
And it needs to be further noted here that those fantastic figures like 30-40% increase in Creep-rupture strength etc were for polycrystalline to directional strengthening graduations - for DS to SC graduations, the improvements were far more modest (max 10% or so) and sometimes can even be none between generations as well - as the following schematic shows:
Image

And the answer to that catch is BOTH,
a) Multipath (serpentine) Impingement Cooling air-passage
AND
b) Thermal Barrier Coating

The contemporary turbine TeT improvement is less thru the material technology (including casting techniques like Single Crytal or DS etc) front and more thru the complicated multipath impingement cooling fabrication tech and TBC. That's the frontier of turbojet/turbofan technical research and dev (and not so much on SCBs etc) where an experienced partner is an absolute must.

As just by mastering SCB (from Shivji's AI13 pics and few other such open-source revealing, it seems we are almost there), we will not be able to reach that level of TeT etc. So even if we meet the thrust levels via sledge-hammer techniques like mass-flow increase etc, it will not be efficient enough (read high-SFC "fuel guzzling" and heavier etc).

Oh betw, this above points doesn't take away anything from the need of mastering 2nd-3rd gen SCB etc - as making the turbine blades hollow to allow these multi-path incipient cooling passages etc will require thin-walled blade-material technology while retaining the higher-order of creep-rupture-resistance and Thermal-Mechanical fatigue strengths. And that's exactly where SCB gens become vital (as SC processing normally ensures that the thin section properties are optimised i.e. as section thickness is reduced a standard superalloy ruptures in less time than a simple bar - and that PC > DS > SC is the order of thin section property reduction).

So long-story short (will bring these points in some more detail in the Kaveri saga thread), if we can master the required raw-material-forming and casting technology for 3rd Gen SCBs etc well and good - but if we can't, we can still make do with DS ones (and achieve maybe somewhat conservative but still acceptable performance parameters) PROVIDED we have considerably progressed on the blade-cooling and the TBC technology.


2) Wrt Compressor Blisk technology - the temperature regime we have already aimed for in the current Kaveri precludes Ti usage in the last couple of stages of the HPC and we are firmly in the Polycrystalline Superalloy regime there-in. Manufacturing blades and disks with such complex metallurgical superalloys is a huge challenge - which other contemporary turbofan makers overcomes by the using alternate machining paths like Linear Frictional Welding (LFW) etc.

The theory ofcourse is to manufacture the complex-aerofoil-shaped blades and the disks separately (with disks having "slots" to fit-in the blade-roots) and join them by LFW. Problem is standard welding or other joining methods will mean considerable weakness in those joints constraining the rotational/mechanical stress it can withstand. Not so with LFW, where it’s possible (not uncommon actually) to have the joint strength more than that of the blade and disk themselves.

Now we need to beg-borrow this technology (for superalloys and not for some Ti/Steel LFW etc) to achieve relevant blisks (and the associated SPRs without compromising on the weight front) - until then need to live with standard programming of the heavier bolted-blades-on-disk compressor stages.

But again if we have mastered/understood the rotor-dynamics of the HPC, overcome the myriad inter-stage resonant-vibration impacts etc, controlled the interstage shock-waves in a 1.6M or so tip-speed compressor stages etc etc etc, absence of blisks can be lived with. Yes it will not be super-duper 30 OPR achieving stuff, but maybe a SDRE 27 OPR regime, enough to achieve those thrust figures etc.


3) There are other seemingly small things like Compressor blade surface finish – now in the complex Rotor-CFD world, laminar flow drag (a major source of skin-friction drag losses) is directly proportional to blade surface smoothness. Nowadays in contemporary turbofans, 6-8micron surface smoothness in the HPC stages have been achieved while rest of the world struggles around 30-40micron smoothness of these stages. Another very jealously and closely guarded technology who nobody will ever part with.

And so many such things …


Point is beyond F404 tech, thrust and efficiency improvements in military turbofans are sum-total of such incremental technological (and sometimes even pure engineering and manufacturing) improvements in almost all aspects of CFD, Mechanical, Thermal and Material tech.
And with Kaveri-I we are trying to baseline all these aspects at F404 level. Once that’s done, these other improvements (say in Kaveri-II) will need taking up, some concurrently and a few others, sequentially – a long and hard road ahead, just that we shouldn’t stop trudging along.

So let's keep trucking ...

PratikDas
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Re: Kaveri & aero-engine discussion

Postby PratikDas » 02 Mar 2014 10:30

Maitya Ji, thank you for the trouble you take to pen these layman friendly digests. Quite fascinating material.

SaiK
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Re: Kaveri & aero-engine discussion

Postby SaiK » 23 Mar 2014 13:50

http://bharat-rakshak.com/NEWS/newsrf.php?newsid=20891
imho, they should include GTRE as prime member. it is not bliss ignoring GTRE. or are they thinking of foldin up!?!?

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Re: Kaveri & aero-engine discussion

Postby chackojoseph » 23 Mar 2014 16:38

Air Commodore (Retd) Parvez Khokhar tells me on FB that current version of Kaveri does not produce enough thrust for LCA to take off.

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Re: Kaveri & aero-engine discussion

Postby Aditya_V » 23 Mar 2014 16:56

Wasnt this the same Air commondore who claims Gripen engine can be changed in 33 minutes

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Re: Kaveri & aero-engine discussion

Postby NRao » 23 Mar 2014 17:14

Air Commodore (Retd) Parvez Khokhar tells me on FB that current version of Kaveri does not produce enough thrust for LCA to take off.


What exact purpose does that statement serve?

Is the good Air Commodore aware that the two were decoupled some time back? And, such statements pour more fuel over a topic that leads nowhere?

India NEEDS an Indian engine. That is all there is to it. IF anyone can help please come forward, IF you cannot or do not want to please step backwards (and disappear).

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Re: Kaveri & aero-engine discussion

Postby chackojoseph » 23 Mar 2014 17:49

Oh, please don't fume. Were discussing if current LCA can be used on any of the prototypes for testing. He said (as we already know) a new version is in make.

Parvez Khokhar: Incidentally, the Kaveri engine was never pronounced airworthy, after it completed it's tests on a test bed in Russia. It was not the same size as as the GE-404 engine and major modifications to the airframe would have had to be made, with their inherent challenges, had it been fitted on the Tejas Mk I. The dry and wet thrust produced was approx 78% of the required thrust. It also far exceeded the weight of the 404 and also had a higher Specific Fuel Consumption (SFC), impinging on the range and endurance of the aircraft. As a quick update, the first aircraft to be inducted into the IAF in March 2014, after the IOC, is way behind schedule and is likely to fly only in the last quarter of 2014.

Joseph P. Chacko : its no "airworthy" or not airworthy to be fit in LCA?

Parvez Khokhar : The LCA cannot get airborne with this engine, even if all other modifications were done........

Joseph P. Chacko : They have given any reason, why?
March 20 at 8:32am · Like

Parvez Khokhar : There is much detail published..but simply put, if does not produce adequate power to get airborne, how can you fly with it?


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