Kaveri & Aero-Engine: News & Discussion

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V_Raman
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Re: Kaveri & Aero-Engine: News & Discussion

Postby V_Raman » 16 Aug 2019 23:45

If this is over 330M euros (580 - 250) from Safran - we are definitely missing forest for the trees. Safran will have to fulfill its offset obligations somewhere else for the rest of the money. So it is coming into the country anyway. DRDO does not seem to have the expertise to do this on its own. Safran might think it is not fair to get all the money from them for an entirely new tech as part of offsets. i would think the same way. They did agree to engine collaboration as part of the Rafale deal - which is the big one. Money - we shouldnt sweat over it this much. We had similar issues with the Russian AL-55I for IJT as well. IMO - we should pay up and get the tech instead of wrangling all the time. If we want to play with the big hitters on cutting edge tech collaboration - we need to think differently. We are not that small anymore - evidently as the big hitters are willing to deal with you! Some of the engine collaboration modalities between USA/France had much more onerous conditions agreed upon than simple money! Presidents intervened in those instances to make them happen - time for Modji to do the same here - just like he did for the deal itself! Maybe India should create a sovereign strategic technologies fund to handle situations like these.
Last edited by V_Raman on 17 Aug 2019 00:17, edited 9 times in total.

chetak
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Re: Kaveri & Aero-Engine: News & Discussion

Postby chetak » 16 Aug 2019 23:57

Indranil wrote:So how will the offset obligations be fulfilled now?


didn't boeing build some dabbas/LRU boxes locally as part of their offset obligations for their P8I deal.

using such creative methods of fulfilling offset obligations, these guys could easily help some local company to grow some special idaho potatoes used for KFC "french" fries, no

offset obligations are a wide canvas to paint on.

kaveri core is obviously out.

the israelis also use a very similar methodology of jacking up the prices to opt out of inconvenient promises without paying the penalty of a political fallout.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby NRao » 17 Aug 2019 00:36

V_Raman wrote:If this is over 330M euros (580 - 250) from Safran - we are definitely missing forest for the trees. Safran will have to fulfill its offset obligations somewhere else for the rest of the money. So it is coming into the country anyway. ............................


I have not followed the Safran participation.

So, has Safran spent all that money to tell India the Kaveri does not work? Trying to get a better picture here. Thx.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Rakesh » 17 Aug 2019 01:13

If you have not followed Safran's participation, then you should. That would be time better spent then comments like the above that add no value to the discussion at hand.

Last warning. Next time, there will be a ban.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Vips » 17 Aug 2019 01:17

Does Saturn NPO have any engine it can offer to India? If it is screwdrivergiri or outright purchases (worth $25 Billion for all engines over the life time of the airframes) that will ultimately be done then lets go with somone who stood by us in UN today.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby hgupta » 17 Aug 2019 01:32

maitya wrote:
hgupta wrote:Penny wise pound foolish.

The Americans, Soviets, and the French did not spend hundreds of millions to develop their engine technology. They spent billions of dollars in their R&D to develop basic versions of fighter jet engines and more billions to refine those engines into the engines we know today and DRDO is balking at ponying up $500M to learn billions of dollars worth of knowledge and save some years in the process when after learning all the knowledge they could use it to make $25 billion dollars worth of engines in the future?

I simply do not know what to say. Sometimes DRDO doesn't have a long term or strategic foresight and get bogged in the minutiae details. Essentially they are missing the forest for the trees.


Wrt the highlighted part ... pls could you list out, what exactly DRDO GTRE learn from such a JV? Atleast some items, can be listed out, right?

And how exactly is the "... $25B worth of engines ..." arrived at?


For starters, they could learn how to construct their own testing bed and vacuum testing chambers and all other testing rigs and do it in house instead of relying on Russian testing rigs and come up with their own data and build on their own data in a much faster manner instead of doing it in piecemeal fashion. Something that they haven't done before and still are not doing right now.

Also they will learn how to make machines that can precise mass manufacture high quality components and assemble them in a reliable efficient manner. And also be able to incorporate incremental changes after rigorous testing into those machines that produce those high quality parts. Something that they haven't done before and still are not doing right now.

As for the $25B worth of engines, easy - for the lifespan of a fighter jet which can last up to 45-50 years, it will take 3-4 engines (Midlife upgrades only happen every 5 to 6 years and the lifespan of an engine is 10-12 years). If you are planning on 800 LCA fighters total , that comes out to 2400-3200 engines. For the AMCA program where it has two engines and projected numbers are 250- 300 planes, that's 1200-1800 engines. Adding them altogether is 3600-5000 engines. On the low side, at $5M per engine you are looking at $18B-25B worth of engines. If it goes up to $7M per engine that's $25.2B-$35B. Realistically speaking, you are looking at $44B after taking into consideration of all life cycle costs into factor such as maintenance, 24/7 support, spares, etc.

So the number I quote, $25B, is really on the low side. You may say that the F414 engine only cost $4.1M but that was two years ago and you need to factor in the inflation cost and cost of setting up the infrastructure to mass manufacture the Kaveri engines. So realistically, any engine you buy is at the low end of $5M. Heck, the Honeywell engine upgrade is rated at $6M per engine and that is for a 40 year old engine design with far lower specs than the F404 engine.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Prasad » 17 Aug 2019 04:26

maitya,
Forgive me if this sounds utterly stupid but I have a q.
Ti-Al (I'll take 6Al 4V) has a density half that of cmsx4 plus, or thereabouts (4.4g/cc vs 8.9g/cc). Ti problem is the >600C region. Midhani SuperNi alloy in the kaveri hpc operates at around 750C. And they have Ti alloys developed for other processes that can work fine at 550/600C.
So, given the density differences, why not just apply a TBC layer on top of the Ti alloy and stuff it into the hpc stage and get weight savings by magic?

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Cain Marko » 17 Aug 2019 04:44

Bad news. This is effed up at so many levels. Frickin penny pinchers. They'll probably waster another 10 years on just deciding what route to pursue.The m88 core is capable of being upsized to 9kn. Yes it's a steep price, but if it means an engine that India has full control over and can power 100s of future fighters without being armtwisted over US sanctions or Russian shenanigans, it is all worth it.

At this point, I hope modi/shah peek into this and Get it done.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby fanne » 17 Aug 2019 08:10

Boss DRDO is not the right agency to decide should be spent $500 Million or not, it is not their call. Their call is can they do the technology? They have assured multiple times in the past and failed. Someone (mod) should step in and order it. Have the knowledge skill flow to 2-3 groups - One DRDO agency, other some private big firm, other a bunch of enthusiast (but small player), even HAL. So that in their inflated ego even if DRDO refuses to learn, someone else will.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Aditya_V » 17 Aug 2019 12:45

fanne wrote:Boss DRDO is not the right agency to decide should be spent $500 Million or not, it is not their call. Their call is can they do the technology? They have assured multiple times in the past and failed. Someone (mod) should step in and order it. Have the knowledge skill flow to 2-3 groups - One DRDO agency, other some private big firm, other a bunch of enthusiast (but small player), even HAL. So that in their inflated ego even if DRDO refuses to learn, someone else will.


Sar, that report looks like a fishing expedition, to ask sensational questions so that important information can out of rebuttals or even informally. Things are not leaking out as they used and many people need info.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 17 Aug 2019 15:16

MohanMP wrote:
chetak wrote:as posted earlier, I have seen the SCBs beingklopp produced in GOI facilities. Only DRDO/GTRE can confirm for sure if this has progressed beyond the experimental stage.

Problem is that everyone involved will have to cede a bit of control for the viability of the project and the usual and bitter turf wars have scuttled many a viable project.

SC blades are made in the country.

We have infra to investment cast of SC blades. We have been doing it for last one and half decade. In early days rejection rates were high. That has been under control. However we never used the infra for our own design till now. Oviousely we also produce DS blades. All types of blades are produced. However we never utilized the skill and the infra for our own design. Our designers did not design taking into consideration our available MFG and testing facility of engine. Even HAL overlooked it.

Designer should know the available manufacturing resources for implementation of design.


hi,

Is it possible for you to be more specific on HTSE SCBs..? AFAIK they are CMSX4 SCBs. Uncooled. TBC done in India, perhaps by ARCI ( Yittrium stabilized Zr coating). But who is making the Single Crystal castings..? Is it HAL's in-house production..?

If you cannot disclose details that's just fine.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 17 Aug 2019 15:26

The list of various performance and QA test facilities at GTRE, from DRDO website:

1000 HP cyclic spin test facility.
10000 PSI Pressure Test Facility.
150 HP Fuel System Test Rig Facility
15000 PSI Pressure Test Facility.
250 HP Fuel System Test Rig Facility
300 HP cyclic spin test facility.
3000 PSI Pressure Test Facility.
30000 Nm Shaft Fatigue Test Facility
3D Co-ordinate Measuring Machine (MAUSER)
3D Co-ordinate Measuring Machine (MMZ - G)
3D Co-ordinate Measuring Machine (MMZ-T)
3D Co-ordinate Measuring Machine (Prismo Navigator)
500 HP Fuel System Test Rig Facility
565 Nm & 1130 Nm Quill Shaft Fatigue Test Facilities.
580 PSI Pressure Test Facility.
60000 Nm Shaft Fatigue Test Facility
650 HP cyclic spin test facility.
Actuator Testing Power Pack (ATPP)
Air Turbine spin test facility.
Air Turbine Starter (ATS) test rig facility
Augmented Simulation Rig Facility (ASRF)
Axial Compressor Test facility
Bevel Gear Test Rig
Borescopes (Rigid and Flexible)
Calibration wind tunnel
Combustor Test Facility
Compressed Air Gun
Compressor test facility - 2
Compressor test facility - 3
Dilatometer
Dynamic Spin Rig
Emissometer
Engine Casing Structural Test facility for simulation of multi axial loading capability.
Engine life counter
Engine test cell no. 1
Engine test cell no. 2
Engine test cell no. 3
Engine test cell no. 4
Engine test cell no. 5
Environmental Control System Test Facility To Test Ecs Module Of LCA
First Stage Pump (FSP) Test Rig Facility
Flow Calibration System
Fluorescent Penetrant Inspection System
Foreign body ingestion test facility.
Full power absorption test facility for Gas Turbine Engine Gear box.
Fused Deposition Modelling
Gas turbine After burner Small scale(1-3rd) test facility
Gas Turbine Rotor Blade HCF test facility
Heat Transfer Test Facility
Hydraulic dead weight tester
Immersion C-scan Ultrasonic System
Industrial Videoscope - Videoprobe image processing system
Integrated Nozzle Actuation System (INAS) Test Rig
Lubrication pump test rig (CPSU Test rig)
Nano Indentation System
Online - Exhaust Gas Analyser System
Portable fuel control system test rig facility
Qualification Test Facility For Compact Heat Exchangers of LCA
Radiation Pyrometer System
Radiometric Infrared Thermal Imaging System LWIR
Radiometric Infrared Thermal Imaging System MWIR
Radiometric Infrared Thermal Imaging System SWIR
Reference standard air, gas operated piston gauge dead weight tester
Residual Stress Measurement
Rockwell and Superficial hardness tester
Simulation Rig Facility (SRF)
Stereolithography (SLA) – 5000
Thermal Fatigue Test Rig
Ultrasonic Flaw Detector
Ultrasonic Thickness Gauge (Panametrics 35DL+)
Universal Testing Machine
Warm Air Turbine Test Facility
X- Ray system
X-ray fluorescence (XRF)

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 17 Aug 2019 15:42

maitya wrote:
4) When DMS4 based SC blade tech was already available in house, why didn't HAL engine division use it for the HPT stages for HTFE-25? Why did they constraint themselves to 1200deg K TeT levels via equiaxed casted ones?


HTFE-25 have In718 3D printed cooled blades. rotor blades as well as HPT NGV. Also TET is 1455K.

Image
Image
Image


OTOH, HTSE-1200 have SCB. They are uncooled but have TBC.

maitya
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Re: Kaveri & Aero-Engine: News & Discussion

Postby maitya » 17 Aug 2019 18:24

JayS wrote:
maitya wrote:
4) When DMS4 based SC blade tech was already available in house, why didn't HAL engine division use it for the HPT stages for HTFE-25? Why did they constraint themselves to 1200deg K TeT levels via equiaxed casted ones?


HTFE-25 have In718 3D printed cooled blades. rotor blades as well as HPT NGV. Also TET is 1455K.
<snip>
OTOH, HTSE-1200 have SCB. They are uncooled but have TBC.

Yep ... to construct internal cooling channels in casted blades, the "technology mastering" is not so much wrt investment casting etc - it's with ceramic die manufacturing.
As I mentioned in my previous post (in form of a question), it's well known that DMRL had mastered Medium-Hardness Ceramic Die (of 40HRC levels) using P20 steel - but to go volume manufacturing of casted blades, High-Hardness Ceramic Core Die (of 60 HRC levels) manufacturing is required - these 60HRC level Dies are good for ~1500 injections etc.
(Other route was powder metallurgy based HIP processing for Die manufacturing - DMRL was working on them, but not sure what the current status is).

These are absolute must for arriving at batch manufacturing level of SC casted hollow blades (with cooling channels).

What is intriguing is how come DMRL manufactured DS casted hollow blades of Kabini - as even there the Die manufacturing tech would be same.

Also laser-grilling cooling holes on blades (and vanes) on which TBC had already been applied seems to be very complicated technology to master.

I couldn't complete the last part of the previous serious where I's supposed to delve on these aspects.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 17 Aug 2019 23:15

I just noticed that there was a tender floated by GTRE in Jan Feb 2019 period for Machining, Brazing and TBC for SCB. Most likely for Kaveri. Given the inflow of a number of tenders in last frlew months on various modules, its safe to conclude they are building new prototypes. Are they intending to use SCB now in Kaveri..? Could be. But I am not sure 100%.

Also, another thing I noticed just now, DMRL person during AI2017 Seminar mentioned DMRal has done Preliminary development for 7YSZ ceramic TBC coating using EB-PVD, in collaboration with ARCI. And then a couple of months ago, there was a tender floated by DMRL for setting up a EBPVD facility for TBC. What for..? Industrialization of the Tech..? ARCI was the one perhaps who did the TBC for HTSE1200 SCBs. Looks like a lot is happening in the background.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 17 Aug 2019 23:21

maitya wrote:Yep ... to construct internal cooling channels in casted blades, the "technology mastering" is not so much wrt investment casting etc - it's with ceramic die manufacturing.
As I mentioned in my previous post (in form of a question), it's well known that DMRL had mastered Medium-Hardness Ceramic Die (of 40HRC levels) using P20 steel - but to go volume manufacturing of casted blades, High-Hardness Ceramic Core Die (of 60 HRC levels) manufacturing is required - these 60HRC level Dies are good for ~1500 injections etc.
(Other route was powder metallurgy based HIP processing for Die manufacturing - DMRL was working on them, but not sure what the current status is).

These are absolute must for arriving at batch manufacturing level of SC casted hollow blades (with cooling channels).

What is intriguing is how come DMRL manufactured DS casted hollow blades of Kabini - as even there the Die manufacturing tech would be same.

Also laser-grilling cooling holes on blades (and vanes) on which TBC had already been applied seems to be very complicated technology to master.

I couldn't complete the last part of the previous serious where I's supposed to delve on these aspects.


Just to note, even though HTSE1200 HPT blades are uncooled SCB, they are still hollow, for weight reduction purpose. I am yet to find a pakka ref to who is making those castings.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby ramana » 18 Aug 2019 01:29

V_Raman wrote:If this is over 330M euros (580 - 250) from Safran - we are definitely missing forest for the trees. Safran will have to fulfill its offset obligations somewhere else for the rest of the money. So it is coming into the country anyway. DRDO does not seem to have the expertise to do this on its own. Safran might think it is not fair to get all the money from them for an entirely new tech as part of offsets. i would think the same way. They did agree to engine collaboration as part of the Rafale deal - which is the big one. Money - we shouldnt sweat over it this much. We had similar issues with the Russian AL-55I for IJT as well. IMO - we should pay up and get the tech instead of wrangling all the time. If we want to play with the big hitters on cutting edge tech collaboration - we need to think differently. We are not that small anymore - evidently as the big hitters are willing to deal with you! Some of the engine collaboration modalities between USA/France had much more onerous conditions agreed upon than simple money! Presidents intervened in those instances to make them happen - time for Modji to do the same here - just like he did for the deal itself! Maybe India should create a sovereign strategic technologies fund to handle situations like these.


No. The price, not cost, for new M88 core for Kaveri is
€250M (Safran)+€500M (DRDO) = €750M.
DRDO spent € 240M total for the Kaveri so far.
So €750M.for new core is definitely high.
The biggest problem is the shoe string budget for the Kaveri.
Despite so many higher ups saying it's a national project of importance.
I would ask DRDO how much to redo the core with M88 type technology?
And fund them.
SAFRAN quoting 3x cost of Kaveri is either a rip off or don't know the job.
Can't be latter as they were consulting DRDO in some form or the other since inception.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby V_Raman » 18 Aug 2019 04:05

What % of 500M from DRDO is being paid to Safran? Or is it co-development funds that will be spent in India? I would add a healthy margin for a developed product in this space in the calculations - like 100% over what it would cost to develop - heck even that is low given the time it takes to develop these technologies and mature them to production.

Getting Kaveri out sooner into the field gives India the valuable experience on engine production/operation/improvement life cycle.

The CFM56 collaboration is illustrative here: https://en.wikipedia.org/wiki/CFM_International_CFM56

GE hot section was shipped directly from USA under heavy safeguards and development money was paid to US DOD as well!

Is this was about money, why did we negotiate for this during Rafale deal?

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Re: Kaveri & Aero-Engine: News & Discussion

Postby maitya » 18 Aug 2019 15:24

JayS wrote:I just noticed that there was a tender floated by GTRE in Jan Feb 2019 period for Machining, Brazing and TBC for SCB. Most likely for Kaveri. Given the inflow of a number of tenders in last frlew months on various modules, its safe to conclude they are building new prototypes. Are they intending to use SCB now in Kaveri..? Could be. But I am not sure 100%.

Also, another thing I noticed just now, DMRL person during AI2017 Seminar mentioned DMRal has done Preliminary development for 7YSZ ceramic TBC coating using EB-PVD, in collaboration with ARCI.
And then a couple of months ago, there was a tender floated by DMRL for setting up a EBPVD facility for TBC. What for..? Industrialization of the Tech..? ARCI was the one perhaps who did the TBC for HTSE1200 SCBs. Looks like a lot is happening in the background.

JayS, wrt the highlighted and underlined parts, pls note that the 7-8 YSZ TBC (over a metallic bond coat) providing decrease of the underlying metal-substrate temperature up to 150 deg C etc, is old hand (typically 4+ decade old).
GE has been using 7-8 YSZ TBC etc from mid-1990s (on static parts like combustor linings) and late 1990s on stator (vane)/rotors (blade) of HPT.
So, I'm quite sure/confident that Kabini HPTs would also have some form of YSZ based TBC.


However, the TBC application (and thus its effectiveness) technology though has changed from various type of plasma spray tech to, and nowadays it's almost universally via, physical vapor deposition (PVD) tech.
One of the major reason or switching to PVD tech (other than other-major advantages like life and surface finish) is to address the cooling-hole closure issues.
A PVD deposited TBC typically has particle size of 1.4-1.5 micro-m (compared to >5 micro-m of plasma spray tech) - and that compares very well to typical 0.25-0.50 mm dia of the cooling holes. So, the earlier issues of cooling-hole closure or the cooling flow-reduction is almost eliminated by the PVD technology.
People did try a lot of other approaches to circumvent this problem like, drilling holes after coating, filling holes with wires during spraying, oversizing holes etc - but none really worked well.


The issue with 7-8YSZ based top-coat TBC applications is that YSZ allows for maximum surface temperature capability of about 1200 deg C - beyond that degradation of the coating (in form of reduced strain tolerance and a decrease in thermal fatigue life of the coating) takes place due to changes in microstructure.
So, in most turbofan HPT applications the make-or-break technological aspect is film/convectional cooling effectiveness
i.e. for a Kabini/Kaveri example, the blade-surface film cooling technology, has to be effective enough to bring down the blade-TBC surface temperature from TET levels of 1455deg C to ~1200deg C. So that TBC can further ensure the substrate-metal-blades are operating at about 1050-1100 deg C levels.
This 1050-1100 deg C temp levels are firmly within DS casted blade regime - the SC casted blades can add another 100-150deg C to it, but the applied TBC simply wouldn't support any more temp creep (due to 1200 deg C max phase stability boundary limits).


My hypothesis is, and I'll be the happiest person to be proven wrong, that we haven't seen much of SC casted HPT applications for Kabini/Kaveri, because of this limitation.
So, to summarise,
1) we have reached the max level of TeT that DS casted blades would allow via Kaveri/Kabini - this after implementing a 200-250 deg C temp advantage via film-cooling and TBC.
2) to increase TeT levels by another 100-150 deg C, SC is the way to go.
But the limitation there is film-cooling tech available with us, because it still needs to negate this 100-150deg C temp increase, so that the TBC itself doesn't start spalding and cracking etc. IoW, SC material tech temp advantage will get nullified without further advancement in film-cooling temp technology (a severely closely-guarded tech, which nobody, repeat nobody, will ever part with).


However, recently we have seen reports of Indian Rare Earths Limited developing bi-layer TBC technology of Lanthanum Zirconate (LZ) over Yttrium Stabilized Zirconia (YSZ).

Now referring to my previous post (on this thread) pls note,
1) Lanthanum Zirconate (LZ), has much higher thermal and phase stability - close to 2000deg C. It also has lower thermal conductivity and sintering tendency compared to YSZ.
(Thermal Conductivity - 2 W/m/K of YSZ vs 1.56 W/m/K of LZ)
2) LZ is also less oxygen transparent than YSZ, providing better bond coat oxidation resistance and minimises the growth of TGO (Thermally Grown Oxide layer) - Wiki has good details about TGO and it's impact on TBC.

But the disadvantage of course is LZ has lower coefficient of thermal expansion compared to YSZ - so it cannot be applied directly on the NiCrAlY bond coat.
So, the solution is therefore to have LZ applied as a top coat material over YSZ forming a bilayer TBC.


Now suddenly, with this technology, the issue of 1200deg C limit of TBC is gone - so we don't really need the blade-surface film-cooling tech to be able to bring down the ambient/operating temp to 1200 deg C etc. As this bilayer (LZ-YSZ) TBC will happily work upto a much higher temp (theoretically upto 2000 deg C).
So now suddenly, as a chain reaction, the SC casting tech is attractive again - now we can get those additional 100-150deg C TeT levels without worrying about TBC spalding and other issues. Yes, the temp for the substrate-blades are going to be higher, but that's exactly why SC casting is being attempted for.


Pls further note, DRDO has already assembled and validated the bi-layer YSZ-LZ coated flaps in an aero-engine for test cases involving rapid thermal transients, supersonic flow of combustion products, vibratory loads of about 4 ‘g’, sustained 1,000 h equivalent of engine operation and more than 30,000 nozzle actuations.
And I'm sure testing on rotor blades of the HPT also is going on and news will surface in due course.


So, net-net ...
Kaveri is already delinked from LCA - so French can shove their costly-and-oh-so-advanced M88-core to their sun-never-shine areas.
We are on the threshold of arriving at modern turbo-fan tech etc.

If only GoI et all have the foresight to actually fund the last-mile flight-certification of Kaveri quickly, so that the only other unknown area (of any turbofan tech) of rotor-dynamics and CFD can be certified/baselined - but that's too much to ask from animal-husbandry-degree-yielding-baboons to comprehend let alone plan and execute. :roll:
And for some posters here in BRF, as is evident from some of the previous posts, lesser said the better it is - and silly me, here I was thinking I'm in a forum called Bharat-Rakshak. :x

==============================================================================
PS: I should have posted this AFTER I'd completed the 4 part series write-up - but no b/w, so is getting shelved. Anyway I have posted most of the stuff I'd have posted there anyway.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Suresh S » 18 Aug 2019 19:28

u write well even a non engineer like me could understand most of it. Thx Maitya.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby fanne » 18 Aug 2019 19:41

Maitya sir please write, knowledge is best cure for ignorance (which here most BR people will fall into, it is not cure for mal-intent or severe ego). My only grouse would be, it looks like we have ever been oh so near, just last mile left for the past 20 years!! But if you please ignore my rhetoric, it looks like what is missing is, test beds, taking the POC engine through confirmation. That infrastructure has to be there to support any engine built and with out of box thinking less costly and readily available (afterall engine did get built and certified 50-70 years ago and we have technology which is at least that old). Take a commercially available IL-76 (if we can not tinker with Russia supplied ones due to license) and change it or some of the old bombers to mount these engines (with all the plumbing) - Canberras , Jags (multi-engine to test them, we make almost 90% of it) anything.

ragupta
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Re: Kaveri & Aero-Engine: News & Discussion

Postby ragupta » 18 Aug 2019 20:29

India should acquire other 4 engine plans like 747, Many would be availed in used condition close to their end of life, many are used as freight planes. Buy few and convert into testing machines.

sankum
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Re: Kaveri & Aero-Engine: News & Discussion

Postby sankum » 18 Aug 2019 21:05

Thanks maitya.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby V_Raman » 18 Aug 2019 22:35

Thanks Maityaji for the enlightenment! So this is another case of tech being offered when we are on the cusp of it! Pranaams!!

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Re: Kaveri & Aero-Engine: News & Discussion

Postby vera_k » 19 Aug 2019 02:18

About the lament that there is no flight testing happening, the old version of Kaveri seems to be a tech demo if it is truly not linked to the LCA. In that case, not much value in flight certifying a TD is there?

On the other hand, there is some time to go before the 110-125KN version for the AMCA is needed, so perhaps the decision to wait is not entirely irrational.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Prasad » 19 Aug 2019 03:25

DMS4 is a marginally better material than CMSX-10 according to DMRL. GE -414 uses FSX 414.
And they built their sc blades at koraput iirc. So it wouldn't be far fetched to assume HAL make the htse scb blades themselves.

maitya
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Re: Kaveri & Aero-Engine: News & Discussion

Postby maitya » 19 Aug 2019 12:01

Prasad wrote:DMS4 is a marginally better material than CMSX-10 according to DMRL. GE -414 uses FSX 414.
And they built their sc blades at koraput iirc. So it wouldn't be far fetched to assume HAL make the htse scb blades themselves.


Yep if one goes by raw temp handling capability alone ... quote from my previous post.
<snip>
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).
<snip>
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.

However, actual usage wrt casting HPT blades etc is combination of so many other factors, specifically being able to cast hollow blades with internal cooling paths etc, this advantage is of not much of a consequence.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Prasad » 19 Aug 2019 13:30

Of course. I've seen a few pictures of HAL produced SCBs with cooling holes (which I assume implies internal cooling structures). Whether they have proved such blades made of DMS4 we don't know yet.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby fanne » 19 Aug 2019 17:43

If the Kaveri guys are feeling so confident (and the primary focus should be Kaveri), why they do not develop a follow on engine for Jags. Nothing special or great, just upgrade the same engine with better material, better afterburner, better ....the technology is very 1960s in that Adour engine. Below are the spec, definitely within our capability. In fact the stalled Kaveri looks like is light year modern -
Performance (Adour - Jags, and due to aging the performance has fallen by 25%) -
Maximum thrust: 6,000 lb (27.0 KN) dry / 8,430 lb (37.5 KN) with reheat
Overall pressure ratio: 10.4
Bypass ratio: 0.75-0.8
Fuel consumption: dry 0.81 lb/(lbf⋅h) (23 g/(kN⋅s))
Thrust-to-weight ratio: 4.725

Kaveri (achieved as rumored) -
Performance
Maximum thrust:
Military: 52 kN (11,687 lbf)
Afterburner: 81 kN (18,210 lbf)
Specific fuel consumption:
Military: 0.78 lb/(lbf•h) (79.52 kg/(kN·h))
Afterburner: 2.03 lb/(lbf•h) (207.00 kg/(kN·h))
Thrust-to-weight ratio: 7.8
Bypass ratio: 0.16:1
Overall pressure ratio: 21.5:1

The best measure of engine performance is Thrust-to-weight ratio: 4.725 vs 7.8 a 65% improvement. Agreed not all will translate, but if we can get 20% above the current Adour, it will solve 6 SQ worth of IAF problem. Adour 1960 Tech vs 2019 Tech. I don't know if it violates any licensing agreement. We can always call that engine some other name and say its different.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Kakarat » 19 Aug 2019 18:08

The problem with our system is lack of vision and initiative and a lot of ego
Uprating Jags Adour engine will also give valuable experience to the team and also an engine for various other applications

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Re: Kaveri & Aero-Engine: News & Discussion

Postby JayS » 19 Aug 2019 18:24

HTFE25 is precisely an upgrade for Adour. A much more modern engine in the same thrust class

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Re: Kaveri & Aero-Engine: News & Discussion

Postby sankum » 19 Aug 2019 20:00

HTFE 40, afterburner version of HTFE 25.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby ramana » 19 Aug 2019 21:30

sankum wrote:HTFE 40, afterburner version of HTFE 25.


This one should be fast tracked.
How much (crores) and how long (how many months)?

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Re: Kaveri & Aero-Engine: News & Discussion

Postby fanne » 19 Aug 2019 23:27

Cost and time will only come from HAL. But against Kaveri, this engine is not cutting edge (meaning low risk). It is fully within the capability of gtre and hal. It is mainly a design and production problem and not a material problem (ds blades will do fine do not need sc blades). It looks like vision and ego problem.
It would be good to have a go, we will learn a lot, plus this engine or it’s derivative can go in for hawk engine replacement, uav, ucav etc etc).

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Re: Kaveri & Aero-Engine: News & Discussion

Postby ramana » 20 Aug 2019 00:09

Regarding Kaveri its still being negotiated.
That walking away is typical negotiating stance.
Basically French have stated their price
Lets see and remain calm.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby dinesh_kimar » 20 Aug 2019 19:37

A possible application of Kaveri could have been a Mig 21 re-engine.

It's slightly smaller than the Tumansky R-25, weighs about the same at 1212 kg, and makes 70+ KN, compared to Russian engine's 69 KN.

(The 98 KN speed burst for only 180 seconds has to be engineered in too.)

The turbofan and FADEC control will ensure better fuel savings .

Such an assembly line will give our GTRE folk a wealth of experience in mfg, quality and reliability. (FMEA anyone?)

The use of Kaveri know how for an Adour replacement, as mentioned above, is also worth looking into.

Kaveri is larger and heavier though, present configuration not suitable for a one is to one replacement.

100 Mig 21 need 1 x 120 engines, to run 4-5 years more, before scrapping.

It's definitely well within our reach.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby Rsatchi » 20 Aug 2019 19:53

ACM seems to indicate endgame for '21s.

No one drives cars that vintage: IAF chief on MiG-21s
https://www.deccanherald.com/national/n ... 55723.html

dinesh_kimar wrote:A possible application of Kaveri could have been a Mig 21 re-engine.

It's slightly smaller than the Tumansky R-25, weighs about the same at 1212 kg, and makes 70+ KN, compared to Russian engine's 69 KN.

(The 98 KN speed burst for only 180 seconds has to be engineered in too.)

The turbofan and FADEC control will ensure better fuel savings .

Such an assembly line will give our GTRE folk a wealth of experience in mfg, quality and reliability. (FMEA anyone?)

The use of Kaveri know how for an Adour replacement, as mentioned above, is also worth looking into.

Kaveri is larger and heavier though, present configuration not suitable for a one is to one replacement.

100 Mig 21 need 1 x 120 engines, to run 4-5 years more, before scrapping.

It's definitely well within our reach.

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Re: Kaveri & Aero-Engine: News & Discussion

Postby fanne » 20 Aug 2019 20:31

Naah fitting Kaveri to Mig 21 or Jags is anyway unpractical (different sizes and thrusts etc). This HTFE 25/40 looks promising - This looks like a sweet spot for an engine - it can power UCAV/UAV/trainers/Jags/business jets. The best news, it is within our current ability (of course we have to design and remove any shortcoming), unlike Kaveri that needs hand holding from Snemeca etc. or that extra something has to be mastered. We make the base Adour under license is just icing on the cake, and we can retrofit some of the tech from Kaveri that we have mastered. It is shame why we did not pursue it, even it was for only Jags, we knew we needed a higher power engine. Where is initiative from HAL? instead of building tariners that IAF may not want, this would have been a sure short winner. It can still be with the foreign vendors jacking up price, just put your head down, make it happen. Jags being dual engined, can itself become a test bed. We need not go anywhere


https://en.wikipedia.org/wiki/Rolls-Roy ... meca_Adour

Applications
Aermacchi MB-338 (not-built)
BAE Hawk
BAE Taranis (UCAV development aircraft)
Dassault nEUROn (UCAV development aircraft)
McDonnell Douglas T-45 Goshawk
SEPECAT Jaguar
Licence-built
Ishikawajima-Harima TF40-IHI-801A
Mitsubishi F-1
Mitsubishi T-2

ramana
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Re: Kaveri & Aero-Engine: News & Discussion

Postby ramana » 20 Aug 2019 21:31

DPSUs have all initiative snatched away by MoD and Forces and tight license agreements which no one wants to violate for fear of cutoff of follow-on.
Now we demand they behave like a privately run company!!!

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Re: Kaveri & Aero-Engine: News & Discussion

Postby ldev » 21 Aug 2019 09:20

According to some YT channels/sites, there were 2 issues with the Kaveri engine which Safran was asked to help with, a "rumble" and a "screech" both being manifested in the re-heat portion of engine performance. Supposedly Safran managed to address the "rumble" issue by varying the air/fuel mixture from the various injectors. But the issue of the "screech" which basically resulted in a high frequency acoustic wave which reverberated around the engine from the injectors to the nozzle and back could not be solved. According to these channels, the causes of this high frequency acoustic wave could be fundamental design issues such as the placement of the injectors relative to each other and relative to the flame holders. So Safran expressed it's inability to address this issue to the Kaveri core as is. And the only option was the supply of a modified M-88 core. However this supply would be without any TOT whatsoever. So in reality Safran wanted to supply M-88 cores to the tune of Euro 250 MM (their offset obligation) plus an additional amount of Euro 500 million. But I guess since the decision was already made that both LCA 1 and 2 would operate on the GE-404 & GE-414 respectively, it made no sense to buy M-88 cores from Safran. Help was needed in re-designing Kaveri, not in buying M-88 cores. And so the deal fell through.

Parsing through this information it appears that Kaveri was developing design/close to design thrust levels but the two problems highlighted above would severely degrade engine life and so it is unusable as designed at least for re-heat performance. FWIW.
Last edited by ramana on 22 Aug 2019 00:52, edited 1 time in total.
Reason: Beautiful summary. ramana


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