GTRE Kaveri Engine

Gautam said:
View attachment 39507

Let's go over these deficiencies point by point. I'll try to be brief:

1. Single crystal blades/vanes with EBPVD: Single crystal blade/vane design & fabrication has been established reliably. This is not an issue anymore. Work is ongoing on improving the composition of alloys used for the SCBs.

The issue is the Electron Beam Physical Vapour Deposition (EBPVD) process. This process is used to deposit ultra-thin layers of Thermal Barrier Coating (TBC) on blades & vanes. DMRL has mastered some other PVD & CVD processes. But EBPVD remains out of reach. The main advantage of EBPVD is that the TBC is coated with extreme uniformity. Other deposition processes don't go anywhere near these levels of uniformity in application. Thus, some spots on the blades/vanes end up receiving a lower than necessary thickness of TBC. Those spots become the initiation point of failure.

We currently get EBPVD machines from Germany. They are very expensive & incredible hard to acquire.

2. Powder metallurgy discs: We do have fabrication capacity of powder metallurgy discs. But our discs so far have had unacceptable levels of porosity to be used on a jet engine. DMRL will probably take 4-5 years to increase the specific gravity of these discs to the point where they can start testing them of engines.

We are currently facing a raw material supply problem for some of our powder metallurgy projects. No investments have been made into setting up domestic raw materials factories.

3. Blisk technologies: We have most of what we need to make Blisks of any size. The only limitation is the lack of large isothermal presses. Those are coming up:




4. Damage tolerant disc design: We cannot design damage tolerant disks until we have our own engine FOD test facility. This is an infra & investment issue. Not a capability issue.

5. Polymer Matrix Composite Bypass duct: So far, our expertise in fabricating polymer matrix composites is limited to the resin infusion processes. Resin infusion process produces very good quality composites for structural & surface applications. But the problem of using resin infusion process is that some amount of the resin remains stuck within the composite. This remanent slowly dries away naturally within year or so.

Now, bypass ducts aren't part of the "hot" section of the engine. But they do tend to get heated up. That sudden heat shock will cause the all the resin to burn/dry away all at once. That will change the shape of the duct.

We need to master a new process of making composites. A process that does not need resins. Can be done, will take some time though.

6. FADEC: We can make FADEC systems. But even if we design our own chips, they will be reliant on foreign fabricated chips for the sometime. ISRO's SCL after it upgrades to a 28 nm node can take over this role. Or maybe one of the upcoming civilian fabs. Again, this is an infra & investment issue. Not a capability issue.

7 & 8. Large Structural casings & CERMET Flaps: I need to read more about these before I comment.
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A lot of the stuff we have is old gen. They are not suitable for 5th and 6th gen engines. Some like you mentioned are related to investment, but the main ones are still foreign-dependent.
 
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marich01 said:
Yep, Godrej & Boyce AZAD Engg PTC Brahmos ABI showtech all might be in for the bidding. Could see jv participation from RR or Safran maybe ?
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None of these industries possess expertise in EBPVD TBC process. I'm guessing they'd mfg the components & outsource the said process.

PTC has just taken over Trac Precision Solutions Crewe UK . They've the expertise to machine TF parts designed to withstand < 1600°C. They also undertake TBC though this process is outsourced.
 

S. Jha talks about the Kaveri derivative engine (KDE)/Dry Kaveri. Some highlights:
1. KDE has a new inlet distortion tolerant fan. We knew this already:
1736539888146.png
1736539913295.png
2. KDE gets a new jet pipe. We knew this too:
1736539976645.png
Other forms of signature management have been run on the KDE, like noise, IR etc.
3. New Autonomous FADEC that allows for thrust vectoring capability with a 2D nozzle.
4. Blade/vane composition have changed in the KDE. KDE gets DS blades for LPT section & SX blades with TBC for the HPT section. Original Kaveri had equiaxed blades on the LPT & DS on the HPT section.
5. ARCI & DMRL is working on our 1st gen EBPVD machine. It can coat multiple blades at the same time. Design for the machine is ready. ARCI already have a scaled down prototype working. It is sufficient for small scale production by for industrial use speed of the machine is a concern.
6. KDE will have an indigenous hydro-mechanical fuel control system. Original Kaveri had an imported system. The new system is made to cater to the specific needs of the Ghatak UCAV. The new system is more feature rich. It has variable actuation guide vanes for the fan.
7. KDE has a new anti-icing system. Had posted about this long ago:
Gautam said:
3D printed anti-icing assembly on the variable inlet guide vanes & front bearing of the drive shaft assembly for the Kaveri jet engine. GTRE re-designed the fan for inlet pressure distortion tolerance as will be seen with the use of serpentine intakes on Ghatak UCAV & AMCA.
View attachment 16797View attachment 16798
Click to expand...
8. KDE will have titanium cast oil tank.
9. 2 KDE prototypes have been fabricated. Both prototypes have undergone many hrs. of bench tests in Bangalore & at least 100 hrs. of tests at the high-altitude test facility in Russia. Engine was tested at 13 km altitude in Russia. Both prototypes showcased "carefree handling" over the entire test regime.
10. KDE can produce a max thrust of 46-48 kN at IRA SLS condition at 15 deg C temperature & 100 pascals of atmospheric pressure. Max power has been reduced on purpose.
11. 6 more KDE prototype engines are being integrated by Godrej aerospace from 8 modules supplied to Godrej by other Indian suppliers. The integration work is nearing completion. One of these 6 engines will be sent to Russia for in-flight testing. There would be other bench tests, long duration tests & high-altitude tests.
12. KDE is a 4th gen engine. It will have good parts life compared to other 4th gen engine.
Gautam said:
It's a bit fuzzy. There are no direct answers. I read somewhere that the equiaxed blades with no TBC would have a lifespan of ~500 hrs. DMS4 SC blades can supposedly do 1000+ hrs. I don't know if this 1000+ number is with or without TBC. If we are going for a Niobium/Columbium alloy nozzle then those will need an overhaul at around 1000 hrs too.
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It's hard to know what S. Jha means by "good". I would say they are aiming for 1000 hrs. MTBO.
13. The 6 KDE that Godrej is building will have 80+% indigenous raw materials. The 2 KDE prototypes built by GTRE had 70+ % indigenous raw materials. Some super alloys still need to be imported.
14. Technologies developed for the KDE will feed into the K9+. S Jha hopes that in a future Kaveri variant will be used on Tejas fleet even if it has a thrust shortfall.

HTSE-1200 related:
1. A single prototype was built & run. 1st Indian engine to use SX blades. SX blades were from HAL Koraput.
2. This prototype was one of the reasons why Safran went in for a JV with HAL to make a larger turboshaft engine. Unlike the Shakti, this engine will be a true co-development.
3. S. Jha thinks the HTFE-25 won't be certified before 2027.
 
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Gautam said:

S. Jha talks about the Kaveri derivative engine (KDE)/Dry Kaveri. Some highlights:
1. KDE has a new inlet distortion tolerant fan. We knew this already:
View attachment 39543
View attachment 39544
2. KDE gets a new jet pipe. We knew this too:
View attachment 39545
Other forms of signature management have been run on the KDE, like noise, IR etc.
3. New Autonomous FADEC that allows for thrust vectoring capability with a 2D nozzle.
4. Blade/vane composition have changed in the KDE. KDE gets DS blades for LPT section & SX blades with TBC for the HPT section. Original Kaveri had equiaxed blades on the LPT & DS on the HPT section.
5. ARCI & DMRL is working on our 1st gen EBPVD machine. It can coat multiple blades at the same time. Design for the machine is ready. ARCI already have a scaled down prototype working. It is sufficient for small scale production by for industrial use speed of the machine is a concern.
6. KDE will have an indigenous hydro-mechanical fuel control system. Original Kaveri had an imported system. The new system is made to cater to the specific needs of the Ghatak UCAV. The new system is more feature rich. It has variable actuation guide vanes for the fan.
7. KDE has a new anti-icing system. Had posted about this long ago:

8. KDE will have titanium cast oil tank.
9. 2 KDE prototypes have been fabricated. Both prototypes have undergone many hrs. of bench tests in Bangalore & at least 100 hrs. of tests at the high-altitude test facility in Russia. Engine was tested at 13 km altitude in Russia. Both prototypes showcased "carefree handling" over the entire test regime.
10. KDE can produce a max thrust of 46-48 kN at IRA SLS condition at 15 deg C temperature & 100 pascals of atmospheric pressure. Max power has been reduced on purpose.
11. 6 more KDE prototype engines are being integrated by Godrej aerospace from 8 modules supplied to Godrej by other Indian suppliers. The integration work is nearing completion. One of these 6 engines will be sent to Russia for in-flight testing. There would be other bench tests, long duration tests & high-altitude tests.
12. KDE is a 4th gen engine. It will have good parts life compared to other 4th gen engine.

It's hard to know what S. Jha means by "good". I would say they are aiming for 1000 hrs. MTBO.
13. The 6 KDE that Godrej is building will have 80+% indigenous raw materials. The 2 KDE prototypes built by GTRE had 70+ % indigenous raw materials. Some super alloys still need to be imported.
14. Technologies developed for the KDE will feed into the K9+. S Jha hopes that in a future Kaveri variant will be used on Tejas fleet even if it has a thrust shortfall.

HTSE-1200 related:
1. A single prototype was built & run. 1st Indian engine to use SX blades. SX blades were from HAL Koraput.
2. This prototype was one of the reasons why Safran went in for a JV with HAL to make a larger turboshaft engine. Unlike the Shakti, this engine will be a true co-development.
3. S. Jha thinks the HTFE-25 won't be certified before 2027.
Click to expand...
Since you are very knowledgeable here regarding this Modern 4th-Gen Turbofan. Can you list steps for making it like in order- I mean all of them- not in layman terms obviously. In Parallel, can you also list the Machinery used like Isostatic Forging Press, Coating, EDM etc.

Basically a series of steps of Making& Making Tools for Pinnacle 4th-Gen. If you are generous, can you also do the same for 5th& 6th gen.
 
Rajput Lion said:
For Kaveri 2??
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Some say the 80kn engine, some say for the dry version. Not sure for which yet tbh.
_Anonymous_ said:
None of these industries possess expertise in EBPVD TBC process. I'm guessing they'd mfg the components & outsource the said process.

PTC has just taken over Trac Precision Solutions Crewe UK . They've the expertise to machine TF parts designed to withstand < 1600°C. They also undertake TBC though this process is outsourced.
Click to expand...
PTC and AZAD have build some competence as they supply core part material to RR and other vendors. We have to wait and see which way the tender goes.
 
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mamiam23 said:
Can you list steps for making it like in order- I mean all of them- not in layman terms obviously.
Click to expand...
Most parts of an engine are manufactured conventionally. So, its forging/casting/molding followed by milling/turning the followed by polishing/buffing/coating/painting. We have a good grip on these technologies.

The blades, vanes, discs, combustor, flameholder etc. are the real problematic parts.
mamiam23 said:
In Parallel, can you also list the Machinery used like Isostatic Forging Press, Coating, EDM etc.
Click to expand...
S. Jha is writing an article on DDR on the same.
The Tashkent files said:
@Gautam sir

What is difference between HPC and LPC of KDE and of Snecma M88 meterial vise and other technology such blisk.
Click to expand...
Don't know much about the M88.
 
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Copy and paste from other forum. Interesting stuff.

Below, I have tried to put a list of technologies that most probably, we are trying to achieve, via this joint-dev route (figures in brackets in blue, is what already achieved/exists indigenously via Kaveri program or elsewhere):

Parametric:
1) FAN PR: >=5 (3.4, though 3.7-3.8 achievable)
2) HPC PR: >=6.8-7.0 (6.4)
3) OPR: 30-35 (21.5, though 26.5-27 achievable)
4) BPR: 0.3 - 0.5 (0.16, though 0.2 achievable)
5) TeT: 1600 - 1650deg C (1455deg C, though 1500deg C achievable)
6) Afterburner: 60% of Dry-Thrust with 1.1 Mass-Fraction (45-50%)

Materials:
1) Fan: Ti-Blisks (standard Ti Fan)

2) HPC: Ti MMC based Bling + 1.6-1.8M Blade Tip Speed (Blisk with conventional blade-disk integration via LFW/ECM etc - Transonic Blade tip spee,d 1.1-1.3M)
3) HPC (last/later stages): Ti-Al based or CMC based (Ni Superalloy, PM superalloy for Disc)

4) Combustor: CMC + EBC (Env Barrier Coating), elimination of film cooling (Superalloy + TBC + Film Cooling)

5) HPT Blades: 5th SC Superalloy (DS/SC 3rd/4th Gen Superalloy)
6) HPT Discs: PM Superalloy-Blisk (PM Superalloy std)

7) NGV: CMC (DS Superalloy - maybe even SC Superalloy)

8 ) LPT Blades: CMC (Conventional DS/SC Ni-Superalloy)
9) LPT Discs: CMC (PM of Ni Superalloy)

10) TBC: EBPVD Bilayer LZ-Yt (EBPVD 7/8 Yttria)

11) Coating: Rub Tolerant Coating
12) Shroud/Casings: CMC/MMC (Ni Superalloy)

I'm sure I've missed a lot, but this should be a good starting point, to understand what we are aiming for, technologically, via this joint-dev route.
 
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If you are only going by the metal temperature handling capability alone, then pls note the following:
1) The DS casted blades provide ~14deg C advantage over equiaxed polycrystalline casted blades (e.g. MAR M247, with approx metal temp capability of 950-1050 deg C).
e.g. Kaveri/Kabini uses DS casted blades (and vanes) using Supercast 247A (a variant of CM247LC which is itself derived from equiaxed MAR M247)

2) The 1st Gen SC blades provide another ~20deg C advantage, over these DS casted blades.
e.g. RR2060/PW1480/CMSX3/ReneN4 - 1060 deg C

3) The 2nd Gen SC blades provide another ~30deg C advantage over these 1st Gen SC casted blades.
e.g. PWA1484/CMSX4/ReneN5 - 1120 deg C

4) After that, the 3-5th Gen SC blades are produced with an aim of adding further ~30deg C advantage, as follows:
CMSX10 - 1135 deg C
ReneN6 - 1110 deg C
TMS80/MC-NG/DMS4 - 1140 deg C
TMS196 - 1150 deg C

Pls further note DMS4 is the DMRL developed suddha-desi SC alloys for turbine blade application - and it's almost shoulder to shoulder to best available (i.e. published).
---------------------------------------------------------------
Note - GE uses Rene-6 in F414.
DMRL developed a DS cast version of DMS4 called DMD4 - it was specifically developed for complex turbine aerofoil parts that are difficult to cast in SC form - and also as an cost-effective alternative. Further research continued with DMD4 by adding Ru and it was actaully proved to significantly improve the rupture life etc etc.

So it's obvious simply graduating from Equiaxed -> DS -> SC casting, it's not possible to reach the 1400-1650 deg C TeT capabilities of many modern turbofans.
Also the question obviously arises, how is the 1455deg C TeT of Kaveri achieved given the metal temperature capability of 1050 deg C of DS casted CM247LC based blades?

Answer, of course, and is well known in BRF as well is, from following two aspects:
1) Implementing various Blade Cooling techniques (e.g. Film/Convection cooling) - with this, a decent DS casted blade would provide for 200-250 deg C advantage (eg DS GTD 111) over metal-temperature-handling capabilities.
However a SC casted blade, again with a decently designed blade cooling techniques, would allow this advantage to go upto ~400 deg C.

2) Thermal Barrier Coating (TBC) application - Generally, the 7-8 wt% Yttria Stabilized Zirconia (8YSZ) TBC provides 150 deg C advantage (not to be confused with "thick layer"-TBC-application-capable-surfaces like the combustor walls etc, which can allow as much as 250-300 deg C advantages).


So Kaveri's DS blades gets to 1455 deg C via 1050 deg C (DS Cast) + 250 deg C thru blade cooling + 150 deg C via 8YSZ based TBC
 
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vstol Jockey said:
It appears to me that we have done some significant advance in Hot core tech. I read an article in which we have created a CMC core with a temprature of over 1700*C or 1973K. This seems to have unnerved USA in forcing more controls on us.
Click to expand...
Could you please provide any source or leads regarding this?
 
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