Kaveri & Aero-Engine: News & Discussion

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Arunkumar
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Re: Kaveri & aero-engine discussion

Post by Arunkumar »

^ What about trying it out for Jaguar re-engine instead of F125-IN. Atleast one jaguar can be tried out.
Victor
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Re: Kaveri & aero-engine discussion

Post by Victor »

Design a dedicated ground attack aircraft around it. Something like the Su-25 and A-10. We have been designing planes bassackwards and its time to do it the right way. And lets PLEASE release the RFI to all interested companies, not just pampered PSUs. Kaveri must not be thrown in the dustbin if we can help it but the decision is indeed a good one. Let's move on.

The important part of this is the last sentence: "..India must become self sufficient in making aero engines and our efforts will continue.."
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Re: Kaveri & aero-engine discussion

Post by nachiket »

arvin wrote:^ What about trying it out for Jaguar re-engine instead of F125-IN. Atleast one jaguar can be tried out.
Kaveri is twice as powerful, twice as long and twice as heavy as the F125.
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Re: Kaveri & aero-engine discussion

Post by SaiK »

abandoning kaveri appears to be like desi layoffs! it is important the technology survives, and experience documented and applied for whatever new engine we want to call it gets into LCA/MCA or any IAF fighter jet.
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Re: Kaveri & aero-engine discussion

Post by Yagnasri »

I have some mango questions here gurus -

1. Is the UCAV project still using the Kaveri or not?

2. How can the expertise of Kaveri - particularly Human one be preserved and used? Is it going to be used for New Engine efforts?

3. Any new engine project sanctioned or nothing is in proposal level?
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Re: Kaveri & aero-engine discussion

Post by Neela »

Avinash Chander did say that Kaveri will power the UCAV.
JTull
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Re: Kaveri & aero-engine discussion

Post by JTull »

GoI has finally decided that throwing good money after bad would be a waste. The gravy train had to end. Better to move on then be saddled with legacy issues.

I hope that GTRE will find similar success as IGMP program has found since abandoning Trishul.
Yagnasri
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Re: Kaveri & aero-engine discussion

Post by Yagnasri »

G.T.R.E. may need to be restructured immediately with better project management etc and also may be some greater leadership from MOD for any future projects which require lot of commitment from time and money side.
Victor
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Re: Kaveri & aero-engine discussion

Post by Victor »

GoI should conduct a roundtable with DRDO, GTRE and selected private players big and small. Then the PSUs should be relegated only to research on the key areas with top personnel seconded from private sector while 2 or 3 private players are paid to develop an engine, either singly or jointly as a national project. We have to stop relying on the PSUs on these critical items as if they are our best assets. They are not. GTRE needs to cease being a sarkari sacred cow and should consist of people from 10-20 private and public entities. The current scheme has not worked and we will continue to suffer until we change it.

While the effort to build an indigenous engine will continue, I doubt if Modi will allow the exact same dispensation to jump merrily from a failed project to a new one without a radical change in approach.
member_26622
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Re: Kaveri & aero-engine discussion

Post by member_26622 »

GE makes turbine power plants - large for power plants and small for planes/ships

Equivalent in India >>> BHEL for large power plants, roll off GTRE in to BHEL as semi independent research unit.

Looks quite obvious to take all engine make-rebuild-refurbish facilities spread out between HAL and all under one roof - owned by BHEL. Synergies will come through over.
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Re: Kaveri & aero-engine discussion

Post by SaiK »

tell me what GE does not venture into ?
member_26622
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Re: Kaveri & aero-engine discussion

Post by member_26622 »

^ Question should be which segments is GE number 1 or 2. Rest of the segments where it lags will be sold off as per their long known stance. They are leaders in 'turbine' technology and are doubling down on this key segment.
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Re: Kaveri & aero-engine discussion

Post by chetak »

Victor wrote:GoI should conduct a roundtable with DRDO, GTRE and selected private players big and small. Then the PSUs should be relegated only to research on the key areas with top personnel seconded from private sector while 2 or 3 private players are paid to develop an engine, either singly or jointly as a national project. We have to stop relying on the PSUs on these critical items as if they are our best assets. They are not. GTRE needs to cease being a sarkari sacred cow and should consist of people from 10-20 private and public entities. The current scheme has not worked and we will continue to suffer until we change it.

While the effort to build an indigenous engine will continue, I doubt if Modi will allow the exact same dispensation to jump merrily from a failed project to a new one without a radical change in approach.
people from 10-20 private and public entities.

Private sector means private sector salaries and public entities means public sector salaries.

No one is going to work for charity or in any organisation where such wage discrimination may be practiced.
chetak
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Re: Kaveri & aero-engine discussion

Post by chetak »

nik wrote:GE makes turbine power plants - large for power plants and small for planes/ships

Equivalent in India >>> BHEL for large power plants, roll off GTRE in to BHEL as semi independent research unit.

Looks quite obvious to take all engine make-rebuild-refurbish facilities spread out between HAL and all under one roof - owned by BHEL. Synergies will come through over.
Such as it is, HAL is the repository of much of the aircraft engine related knowledge in India. No sense in bringing in BHEL into the already complicated mix. GTRE has taken all for a ride and who so ever was/is responsible should be penalized. This has been a colossal waste of national resources with the now recognized end result that was glaringly obvious much much earlier. There was no one to bell the cat.
Pratyush
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Re: Kaveri & aero-engine discussion

Post by Pratyush »

Or may be launch a national engine development effort. With Pvt companies forming consortium on the basis of various competencies. Such as materials and other field. The GTRE or any other global player, acts as a consultant, for the effort.

The effort should be focused on the various types of engines that are projected for Indian requirements both civil and military, over the next 15 to 20 years.

Once the competencies have been developed, those consortium can independently develop into P&W and GE, equivalents over the next 20 years.
habal
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Re: Kaveri & aero-engine discussion

Post by habal »

I would seriously have hoped that they could fit this engine into something, just for the sake of it and just so that the long term implications are evident. Why scrap an engine altogether, beats me !
Will
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Re: Kaveri & aero-engine discussion

Post by Will »

They should have developed a LIFT around that engine. Built around the LCA trainer it would make a good LIFT.
Austin
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Re: Kaveri & aero-engine discussion

Post by Austin »

Saurav Jha ‏@SJha1618

The Kaveri project has yielded these pluses: 1) KMGT 2) A usable core 3) served as a hinge for DMRL to develop new materials.
Pratyush
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Re: Kaveri & aero-engine discussion

Post by Pratyush »

Can the usable core be used as the basis for the domestic turbo prop engine for the family of future RTA, being planned for the country.
Thakur_B
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Re: Kaveri & aero-engine discussion

Post by Thakur_B »

GTRE is calling for engine components from Indian industry. For which engine, that seems to be unclear.
http://www.drdo.gov.in/drdo/tenders/vie ... Micro=7986
Will
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Re: Kaveri & aero-engine discussion

Post by Will »

After all the flak they took over the Kaveri looks like GTRE will develop stuff under the radar now and announce when they have a workable product.
Varoon Shekhar
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Re: Kaveri & aero-engine discussion

Post by Varoon Shekhar »

Good article! Rough estimate, what is the percentage of indigenous to imported components in those Koraput engines?
Indranil
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Re: Kaveri & aero-engine discussion

Post by Indranil »

Some new features of the new 105-110 kN engine by GTRE have come forth. Maitya sir, you would love this.

Inlet diameter: 820 mm
Mass flow: 98-100 kg/s
Pratyush
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Re: Kaveri & aero-engine discussion

Post by Pratyush »

A nube question's for on the tender. Who will be the owner of the IPR for the end product??

Also are they looking to add this to the Kabini core for and get a new engine or will this be a new design altogether.
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Re: Kaveri & aero-engine discussion

Post by vina »

Some new features of the new 105-110 kN engine by GTRE have come forth. Maitya sir, you would love this.
Hmm. I had already named this "Ganga". It is the same Kabini core with a new fan stage (more airflow, with higher bypass, core flow remains the same as current Kaveri). Yes, thrust increases, and SFC drops. Note this tender is for a new fan design alone. The co development is not called for the core.

I think they have a working core from the Kabini , along with the necessary high temp materials realised. Only thing is to rename the Kabini as Gangotri!

There really were only two ways to go about this. A new tinku-sa, chickna-sa core (with high temp materials, like the Eco core from M-88) with the current Kaveri LP stage, or a new LP stage with the current Kaveri core (with high temp materials of course). The former for the LCA and the latter for AMCA. The engine for the LCA is really not needed , with the GE engine being available and also local manufacturing possible.

Yeah, a 110 to 120 KN local engine for the AMCA would be great and that is doable if we have the Kabini core working (which I strongly suspect we have). This entire engine is possible within a 5 year time frame (if we get a decent partnership in place, MTU would be a great guys to rope in for the LP stage. They are pretty good in that area and will have least conflict of interest with GTRE . Others like RR, GE, PW, Safran/Snecma will be looking to sell whole engines including hot sections).
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Re: Kaveri & aero-engine discussion

Post by maitya »

indranilroy wrote:Some new features of the new 105-110 kN engine by GTRE have come forth. Maitya sir, you would love this.

Inlet diameter: 820 mm
Mass flow: 98-100 kg/s
This calls for a quick THEORETICAL calc using the quick-&-dirty turbofan sim - here it is:

Image

Ofcourse assuming the already achieved OPR of 21 and TeT of 1723K as in the same Kabini core ... so same thermal and propulsive efficiency etc - betw I'm sure these will increase but not sure by how much!!
member_27164
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Re: Kaveri & aero-engine discussion

Post by member_27164 »

@maitya
from your chart it is clear that basic parameters and 1st order derivatives of current kaveri and ganga are same. so i assume ganga is derivative of kaveri. in such case how will they achieve 100MW work and 88kN dry thrust while current engine does not achieve original design values of 96MW and 76kN respectively? the drdo tender link mentions 'all blisk 3 stage fan'. i did not find mention of blisk in kaveri wiki article (looks like its outdated). so will this blisk technology help in achieving the new figures?
couple of more questions here:
1. tender mentions pressure ratio 5:1 and wiki has mentioned HP and LP pressure ratios. what does 5:1 refer to? LP or HP?
2. indranilroy has mentioned inlet diameter 820mm and wiki mentions 910mm diameter of kaveri (it does not say 'inlet diameter'. but my guess is they are both same.) how will they achieve more mass flow from smaller inlet?
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Re: Kaveri & aero-engine discussion

Post by maitya »

aditya_dange wrote:@maitya
from your chart it is clear that basic parameters and 1st order derivatives of current kaveri and ganga are same. so i assume ganga is derivative of kaveri. in such case how will they achieve 100MW work and 88kN dry thrust while current engine does not achieve original design values of 96MW and 76kN respectively? the drdo tender link mentions 'all blisk 3 stage fan'. i did not find mention of blisk in kaveri wiki article (looks like its outdated). so will this blisk technology help in achieving the new figures?
couple of more questions here:
1. tender mentions pressure ratio 5:1 and wiki has mentioned HP and LP pressure ratios. what does 5:1 refer to? LP or HP?
2. indranilroy has mentioned inlet diameter 820mm and wiki mentions 910mm diameter of kaveri (it does not say 'inlet diameter'. but my guess is they are both same.) how will they achieve more mass flow from smaller inlet?
First of all, pls don't take the Dry thrust value prima facie ... while other ratio-based values can be taken. That chart in it's present form is for a turbojet ... and the BPR will ensure the Core massflow to be lower than 100Kg/sec, reducing the Dry Thrust value - which, per my back-of-an-envelope calc, will be closer to 75KN from core alone.
(plus need to add the bypass thrust contribution as well, which without knowing the fan efficiency is quite difficult to predict - though, normally for such low BPR leaky-turbojets, it shouldn't be more than 15-20% addn thrust).

I'll try and upload an updated version tonight - though accurately calculating the Bypass thrust may not be possible.

But even then looking at the Thrust figures (in it's abosolute value form) is not correct ... as the pretty ham-handed nature of assumptions that I'd made to simplify the calc etc (you can have a glimpse of those assumptions in the Kaveri Thread (in the sticky)).

Best way to use this simulator is to do ratio-based comparative-study etc and try to infer conclusions.
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Re: Kaveri & aero-engine discussion

Post by vina »

But even then looking at the Thrust figures (in it's abosolute value form) is not correct ... as the pretty ham-handed nature of assumptions that I'd made to simplify the calc etc (you can have a glimpse of those assumptions in the Kaveri Thread (in the sticky)).
I think these following values will be reasonable assumptions to make of your calculations

1) OPR approx 25, mabye 27 (assuming 26 will work best I think)
2) TeT around 1800K
3) Bypass ratio around 0.4 to 0.5 (0.45 as a value will work well, 0.5 seems on the upper end , while 0.4 will be eminently doable)
4) Wet thrust approx 1.4 X dry thrust
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Re: Kaveri & aero-engine discussion

Post by maitya »

Have updated with simulator (asuming an achieved Fan Pressure Ratio of 4:1) ...
Image

Also pls note have added a newer forecasted model where the core achieves the key performance parameters that was originally specified for Kaveri/Kabini but with this bigger Fan and larges Massflow (and higher BPR of 0.5).
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Re: Kaveri & aero-engine discussion

Post by Gyan »

IIRC long time ago I remember reading a DRDO honcho commenting that we need bypass ratio of around 0.58 but I am going by memory alone
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Re: Kaveri & aero-engine discussion

Post by Indranil »

The original EOI had more information (though different massflow). May be useful to fine-tune your calculations.
indranilroy wrote:BREAKING NEWS :-o
GTRE's next engine (from tender to Design & Development of three stage blisk fan)
Design and development of three stage 5:1 pressure ratio all Blisk fan for 75/110 kN thrust class engine. The broad design specifications and constraints are defined as below.

Code: Select all

---------------------------------------------------------------------------------------------------------
|               Design specifications: ISA-SLS - P1=101.325kPa ; T1=288.16K                             |
|-------------------------------------------------------------------------------------------------------|
| Parameter             | Value        | Constraint                | Remark                             |
|-----------------------|--------------|---------------------------|------------------------------------|
| Mass flow rate        | 85-87 kg/s   |                           | ~5% growth potential should be     |
|-----------------------|--------------|---------------------------| available. GTRE would like to      |
| Pressure Ratio        | 4.8-5.0      |                           | participate in the design process. | 
|-----------------------|--------------|---------------------------| The mode of participation will be  |
| Isentropic efficiency | 83-84%       | Minimum 83%               | deliberated later.                 |
|-----------------------|--------------|---------------------------|                                    |
| Surge margin          | ~22%         | Part speed margin should  |                                    | 
|                       |              | be more than 25%          |                                    |
|-----------------------|--------------|---------------------------|------------------------------------|
| Max inlet diameter    | As needed by | ~780 mm                   | Selection of material will dictate |         
|                       | the designer |                           | maximum rotational speed.          |
|-----------------------|--------------|---------------------------|                                    |
| Rotational speed      | As needed by | Nil                       |                                    |
|                       | the designer |                           |                                    |
---------------------------------------------------------------------------------------------------------
Time frame for the above activities up to component level aerodynamic testing, aeromechanical testing for generating performance map, structural testing relating to life and safety is approximately five years (60 months). It also includes manufacture of five sets of hardware for testing and evaluation of above tests.

SCOPE OF WORK: The scope of work includes Design of Fan, CAD/CAE Simulations & Analysis, Prototype Development, Performance & Functional Testing and Proving of the Fan. This includes certification level tests as per MIL 5007-E .Further, it also includes transfer of production technology to GTRE which is inclusive of setting up of infrastructure, training and assistance in manufacturing of blisks.
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Re: Kaveri & aero-engine discussion

Post by Gyan »

Can we now be talking about three engines:-

Kaveriwith Mass flow Rate78 kg/s, Inlet of ??mm and Power 56/79kn -76/107kn

Yamuna with Mass flow Rate 85-87 kg/s, Inlet of 780mm and Power 75/110kn

Gangawith Mass flow Rate 98-100 kg/s, Inlet of 820mm and (Power 88/123-98/137kn as predicted in above posts)
member_28108
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Re: Kaveri & aero-engine discussion

Post by member_28108 »

One thing the Kaveri is not shelved.The project continues.There will be further testing at high altitudes,The core will be used for other purposes.It will be fully tested and validated and may be used for other purposes and will be the basis for different engine(Ganga Yamuna or whatever )
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Re: Kaveri & aero-engine discussion

Post by sivab »

:D :D :D Good news from DMRL via Saurav Jha

https://twitter.com/SJha1618/status/553 ... 36/photo/1
Image

Don't miss the last line in picture.

:D :D :D DMRL now has SCB tech. BETTER than what is used in AL31!!! :D :D :D

This will now go into next gen Kaveri (~110KN) for AMCA and possibly LCA MkII.
sivab
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Re: Kaveri & aero-engine discussion

Post by sivab »

http://www.drdo.gov.in/drdo/English/DRD ... -ebook.pdf
GTX-35-VS Engine
During the year, 122 h of engine testing have been completed on five prototypes, viz., K5, K6, K7,
K8 and K9 of Kaveri engine. Notably engine endurance has been established for K7 engine through
continuous testing of 50 h in one build
. HP compressor was tested at Anecom, Germany. Various tests
like aeromechanical mapping, performance mapping, and inlet distortion tolerance tests were carried
out. The improved HP Compressor gave 3 per
cent improved mass flow rate and increased pressure
ratio. 50 h of testing was done at various inlet conditions
Small Turbo Fan Engine
Under this project, 3-D model of the engine and its components have been created. Detailed CFD
analysis has been carried out to establish the targeted engine performance. The engine is expected to
provide 410 kgf thrust at 0.75 kg/kgf-hr specificfuel consumption (SFC). Manufacture of the components
with indigenous material is under progress
. Development of LRUs and accessories has started. First
prototype of the alternator has been realised. The alternator is designed to operate at 53,000 rpm
speed and deliver 4kW power. High pressure (HP) and low pressure (LP) turbine rotor blades, Nozzle
Guide Vanes (NGV), and HP NGV casings were realised with indigenous technology
Single Crystal Blades and Vanes for Aero-engine Applications
DMRL has demonstrated single crystal casting process for high pressure turbine blades (HPTB)
and high pressure turbine vanes (HPTV) having intricate cooling channels to be used in advanced
aero-engines. This is an advanced technology in comparison to what HAL, Koraput, currently has for
hollow single crystal HPT rotor blades (used in SUKHOI fighter aero-engines)
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Re: Kaveri & aero-engine discussion

Post by Indranil »

sivab wrote:http://www.drdo.gov.in/drdo/English/DRD ... -ebook.pdf
Small Turbo Fan Engine
Under this project, 3-D model of the engine and its components have been created. Detailed CFD
analysis has been carried out to establish the targeted engine performance. The engine is expected to
provide 410 kgf thrust at 0.75 kg/kgf-hr specificfuel consumption (SFC). Manufacture of the components
with indigenous material is under progress
. Development of LRUs and accessories has started. First
prototype of the alternator has been realised. The alternator is designed to operate at 53,000 rpm
speed and deliver 4kW power. High pressure (HP) and low pressure (LP) turbine rotor blades, Nozzle
Guide Vanes (NGV), and HP NGV casings were realised with indigenous technology
This is good news. The SFC of 0.75 kg/kgf-hr is significantly better than 1.05 kg/kgf-hr advertised earlier. This is on par with the best in the world in this thrust category.
Image
member_28108
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Re: Kaveri & aero-engine discussion

Post by member_28108 »

Regarding the Kabini core ,in the exhibition they mentioned it has a very well working core.
maitya
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Re: Kaveri & aero-engine discussion

Post by maitya »

sivab wrote::D :D :D Good news from DMRL via Saurav Jha

https://twitter.com/SJha1618/status/553 ... 36/photo/1
Image

Don't miss the last line in picture.

:D :D :D DMRL now has SCB tech. BETTER than what is used in AL31!!! :D :D :D

This will now go into next gen Kaveri (~110KN) for AMCA and possibly LCA MkII.
Yes definitely good news from the sheer turbofan metallurgical technology capability/maturity ascendency perspective.

Pls refer to one of my posts on TeT vs Turbine blade tech etc in the Kaveri sticky here:
First the co-relation of Thrust vs TeT vs OPR relationship - if we are not able to increase the OPR, the specific work can be increased slightly by increasing TeT, provided it's a quantum jump. Refer to the corresponding graph here.
Image

But that also means, for given core (so for Kabini), if we are not able to get a big-enough TeT enhancement, for an unchanged OPR, the Useful-Work (or thrust) increase would be minimal. Since none of us would have access to similar plots for the Kabini core, we can't say if this TeT increase will result in any significant Thrust increase etc.

But even then, assuming we get a larger increase in thrust because of this TeT increase, let's hold on to our lungi-dance for a minute, shall we:

Pls refer to another of my posts in the Kaveri sticky - here:
maitya wrote: As it can be clearly seen that the stagnation temperature rise across the stage increases with the tip Mach number squared, and for fixed positive blade angles, decreases with increasing mass flow. Fig 4 is the corresponding schematic representation.

So what does the above representation mean from a Kaveri perspective. Well, as I’ve mentioned above, there’ll be an attempt to better the current Compressor SPRs of Kaveri via TeT improvements. This will essentially mean increase the compressor blade rotor tip speed which, as the above schematic shows, will result in increase in ambient temperature across the compressor stages.

Increasing temperature on the compressor stages will mean breaching the 650-700deg C (or so) max operating temp point of the Ti-based Compressor blades. So we should see an attempt towards junking the current Ti-based blades and switching to Equiaxed-casted Ni-alloy based compressor blades atleast for the later HPC stages (where the peak temp will be reached).
See the dilemma ... we get the SC based Turbine-blade tech and increase the TeT by say 50-70deg C - which means for the same turbine mass, the amount of work that we now get from turbine is going to be higher.

This higher amount of work from the Turbine will increase the rotating speed of the compressor stages increasing their SPR and thus the overall OPR. But increasing Compressor SPRs would mean increase in ambient temperature across compressor stages.
Now that would mean, the temperature gradient across the first couple of stages would still be tolerable for the Ti based blades but higher across the last couple of compressor stages where it will conveniently breach the ~600deg C limit for Ti.

To solve it, these stages would have to resort superalloys (not the fancy SC or DS ones but the SDRE Equiaxed ones would do) - but casted superalloys have higher density (and thus weigh more for the same volume or geometry) - again increasing the overall weight of an already over-weight (by ~135Kg) engine is it.

To make it slightly more complicated, the last 2 stages of the 6 stage HPC are already made up of casted superalloys - since we wouldn't know how much more temp-and-structure tolerance level (aka head room) of these are there currently , we will not be able to gauge if we need to move to diff composition of these superalloys. Also critical would be finding out, that with this increase in TeT, what the temp gradient increase level is across 3rd and 4th level (i.e. how closer will they be to ~ 600deg limit of the Ti).

OR

We slightly increase the mass flow (by artificially enlarging the core) thru the compressor stages (refer to the Euler turbine equation above) and keep a tight-lease on this temperature increase across HPC stages.
But then that would mean going back by atleast 3-4years and do the whole assembly-testing-flight testing etc etc cycle once again.

OR

But there can be a better solution as well.
Can we keep the make the current compressor stages more "heat-resistant" and tide over this. Possible, if we are able to master the casting methodology etc for the intricate internal-cooling-passage-based blade cooling tech (with hollow shafts which would carry-in the cold-air and also carry out (towards the combustor) hot air etc). Pls note until very recently we were importing the wax-and-ceramic based moulds for the HPT stage (for the DS based blades with intricate internal-cooling-passages). But then again that's absolute cutting edge of the compressor blade tech.


Bottomline is, IMO, as far as Indian turbofan tech development is concerened, the Achilees heel right now is to somehow master the contemporary compressor technology (which brings the OPR to 27-30 levels) while keeping the overall weight low (in a turbofan the Fan and HPC contributes to the majority of the weight). That brings us firmly to areas of (also details can be found here and here,

1. Good-old 3D CFD codes*
2. Low aspect ratio (aka wide chord) blade design and manufacturing
3. Manufacturing (mass-level) capability of multi-circular arc profile compressor blades
4. Blisk tech (for HPC and even the Fan)
5. High speed milling
6. Electro-Chemical machining,
7. Linear Frictional Welding,
8. Wax/Si based mould fabrication tech etc even for light weight materials like Ti,
9. Intermetallic Titanium Aluminide (TiAl - with 50% density level of current superalloys) based compressor blade and disc manufacturing ability (EBM etc.)
10. Surface-finish tech (~5-6 micron levels) for compressor
ityadi ityadi.

*Essentially, as the grand-mullah Enqyoobuddin Gas-turbini had sermoned many moons back, get hordes of DOO and PIGS onto this with freedom of destroying a couple of cores, with harsh timelines and supervision and see the results – PissBUH!!
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