Kaveri Engine

[woaa]

Kaveri has 52/81 kn because of temperature and pressure ratio achieved is suboptimal. Temperature achieved is 1470 c while goal is 1880 c . Pressure ratio achieved 21:1 while goal is 27:1 . 52/81 kn thrust achievement are because of metallurgy limitation not because of degine limitation . Later reports come of scb of 100 c temperature better durability are ready . These blade definitely has gone into Kaveri with better thrust than 52/81 but exact figure not come in public domain but it definitely more and may be between 85 to 90 kn . Actually if original objective of Kaveri is achieved it is a engine of f414 class with dry thrust of 62~65 kn and wet thrust of 95~100 kn . A interesting facts is that f414 has 890 mm diameter while Kaveri has 910 mm mean more surface area for air flow . If same level of metallurgy come to Kaveri with achievement of 1900 c and 30:1 total pressure ratio Kaveri generate more thrust than f414 . If thrust to weight ratio of 10:1 achieved for Kaveri it definitely has more thrust that f414 epe .
My question is very simple .......
Is Kaveri snecma engine going to achieve ~ 100 kn goal with a thrust to weight ratio of 9:1 or ~115 kn with thrust to weight ratio of > 10:1 ?

i dont believe it. can you explain it more ?

 

[Kunal Biswas]

Their can`t be another better explained post, Read the thread ..

i dont believe it. can you explain it more ?

 

[BON PLAN]

Let me give you a hint: 4-5 countries can independently design cryogenic engines, 30-40 countries can design gas turbines.

I think main problem with Kaveri was to try to developp from A to Z a very effective and complex engine from a first attempt.

The rocket indian programm is older, and moved step by step. It was a safer attitude.

 

[kunal1123]

I think main problem with Kaveri was to try to developp from A to Z a very effective and complex engine from a first attempt.

The rocket indian program is older, and moved step by step. It was a safer attitude.

yes and add to that no political will to support . i have read some where that the fund was so low around 2009-2011 that they cannot even buy fuel for test run some time.

 

[HariPrasad-1]

Actually, metallurgy is the most difficult part even in the design of cryogenic engine. One deals with metals for extreme cold temperatures, while the other (turbofan) deals with metals for extreme high temperatures!!

The difficulty for each cannot realistically be gauged by how many countries have mastered it. (run of the mill) Gas turbines are needed in the tens of thousands and hence driven by business needs most attempt and several succeed in their design and build efforts (for various degrees of efficiency). On the other hand Cryogenic engines are not that essential other than for space exploring countries - as such few attempt and fewer succeed.

That said, gas turbines are different from turbofans for aircraft applications (even though the broad principle of compression and ignition of the fuel mixture may be similar). The requirements for weight reduction and fuel efficiency is far far greater for a turbofan (for aircraft application) than it is for gas turbines - and there in lies the rub!!

I believe we had 1450*c metallurgy when we made kaveri initially. With the advancement in our metallurgy and in latest single crystal blade, we have surpassed 1600*c + and be 1650 * c.

 

[wuzetian]

yes and add to that no political will to support . i have read some where that the fund was so low around 2009-2011 that they cannot even buy fuel for test run some time.

I can understand the issue of this erratic funding . Experiencing it first hand now , no POL for duty [emoji23] [emoji23] [emoji45]

 

[Alok Arya]

I believe we had 1450*c metallurgy when we made kaveri initially. With the advancement in our metallurgy and in latest single crystal blade, we have surpassed 1600*c + and be 1650 * c.

Actually It ds blades of 1470 c durability which are in Kaveri of 52 dry and 81 wet ( flat rated to 78 ) at 2011 Russian tested engine . Pressure ratio achieved is 21.5 . And this is near the contemporary tech standard of 90s . But world change faster than us and this is not jump but continuous progress of tech in field of metallurgy , alloy , thermobaric coating , casting , disk forging , blisk casting , linear friction welding for blisk manufacturing from different alloyed disk and different alloyed blade , fluid dynamics study of air mass flow of engine , computer assisted degining of stages , wide cord blade for that , placing and spacing of blade on disc etc etc

 

[indiatester]

Actually It ds blades of 1470 c durability which are in Kaveri of 52 dry and 81 wet ( flat rated to 78 ) at 2011 Russian tested engine . Pressure ratio achieved is 21.5 . And this is near the contemporary tech standard of 90s . But world change faster than us and this is not jump but continuous progress of tech in field of metallurgy , alloy , thermobaric coating , casting , disk forging , blisk casting , linear friction welding for blisk manufacturing from different alloyed disk and different alloyed blade , fluid dynamics study of air mass flow of engine , computer assisted degining of stages , wide cord blade for that , placing and spacing of blade on disc etc etc

How much has metallurgy changed from 90's to date?
Which engines have incorporated those technologies?

 

[Alok Arya]

After returning from Russia with a successful engine of contemporary 90 tech our scientists found that cash flow to this complex , vital program of national interest has been sucked by our import favouring babus and politicians. Finally they are even not able to procure fuel for running of engines they have build . In 2014 they decide to shut the program but to keep alive tacit knowledge and know how acquired during programme they recognise the 14 field of vital importance and research in these field will be continue at least on paper even in absence of money .

 

[Alok Arya]

What change in 2014
A new regime with new mod come in power and start showing interest in Kaveri come in power .
SCB tech come to India with Sukhoi which Russia gives us after so many hurdles and delay . This is first generation tech . SCB blade ( 70s tech) of first generation are low in temperature durability than ds blade ( tech of 70s but considered more advance than scb at that time ) . DMRL took this challenge, play around this first generation tech , and from this a second generation scb (100 c more durable than ds blade of 1470 c of kaveri of 2011) and ds blade based on an Indian degined nickle based superalloy developed .
These two thing lead to designers to sit again to improve engine .

 

[Alok Arya]

But new mod , better scb is just beignig of challenges. New scb mean higher tet , higher rpm , higher centrifugal force on low pressure blade and disc in new conditions of higher temperature and pressure . This means new alloy of better tensile strength and temperature durability for disc , better disk forging method , new alloy for blade for better temperature durability as well better centrifugal force in presence of higher pressure ratio for low pressure stages , and blisk to join these blade and disc of different alloy for dealing with higher centrifugal force transmition as well as for weight saving . So now a lot of things are to be do with low pressure stages also . But it is not end . Wide cord blade their computer assisted degine based on mass flow dynamic study of engine , proper spacing and angle on disc are also few thing among other to be dealt for full realisation of increase tet in term of thrust and pressure ratio achievements .

 

[Alok Arya]

And also each generation of scb is different from previous generation by 70 to 80 c . Major chunk of temperature come from thermobaric coating , which may be in order of 200 to 300 c depending on techniques .
Now it is turn of mod to realise the amount of work to be done . They quickly engage each and every institute of Indian scientists arena with allocation of fund for development of very mentioned technologies . Also mod realise that tech development is not a overnight phenomenon . Even after development of technologies you have to go through actually placing all these in single tube so called engine and than will start ground testing, test bed testing , dual engine fighter plane testing , then finally single engine testing and all these will takes a large amount of time , realising problem reacting it in next stage etc etc .

 

[Alok Arya]

So a need of foreign expert needed . The view of mod was that even fixing Kaveri in form of consultancy will give our scientists a chance to quickly acquire the tacit knowledge and know how of this complex technique power pack fixation . And playing around it in future lead to fixing Kaveri based on in house developed technologies . During this period of consultancy and fixing of Kaveri they will be acquire the metallurgy composing of various stage , designing of blade , their placement on disc , role and use of computer simulation etc etc . So mod refuse to sign rafale deal until offset in form of tot will not make solid progress on ground . And this is very wise place step of mod .

 

[wuzetian]

So a need of foreign expert needed . The view of mod was that even fixing Kaveri in form of consultancy will give our scientists a chance to quickly acquire the tacit knowledge and know how of this complex technique power pack fixation . And playing around it in future lead to fixing Kaveri based on in house developed technologies . During this period of consultancy and fixing of Kaveri they will be acquire the metallurgy composing of various stage , designing of blade , their placement on disc , role and use of computer simulation etc etc . So mod refuse to sign rafale deal until offset in form of tot will not make solid progress on ground . And this is very wise place step of mod .

Thank you Alok Arya for this wealth of information regarding Kaveri engine problems. May more people like you contribute in this forum [emoji3] [emoji3] [emoji3]

 

[Alok Arya]

I can safely say that this offset of snecma Kaveri also have another dimension . Who will like to loose a business of 2000 engine for amca at the cost of 6 to 8 million totalling to 12 to 16 billion usd . I think snecma Kaveri will be ~65 kn dry and ~95 kn with a tweaking of better metallurgy to ~75 kn dry and ~115 kn wet for Tejas and amca respectively . This give us a confidence to negotiate with Uncle Sam for better tech tot . However it is news on net that USA ready with complete know how of f414 110 kn but it link it to f16/18 fighter jet and want to retain all IP , means we will be not able to use this tech in future program without their permission . What will happen is future . So wait .

 

[BON PLAN]

How much has metallurgy changed from 90's to date?
Which engines have incorporated those technologies?

maybe ceramic coat ?
New technology (cast) for cooling chanel ?
3D printer ?

and , appart metallurgy : Best numeric modelization so as to monitor more precisely (with less margin) the engine?

 

[Scrutator]

I believe we had 1450*c metallurgy when we made kaveri initially. With the advancement in our metallurgy and in latest single crystal blade, we have surpassed 1600*c + and be 1650 * c.

Have they reported any improvement in the thrust output with this high temperature?

 

[Alok Arya]

Have they reported any improvement in the thrust output with this high temperature?

No such report in media /net . One guy self claim to be closer to project has said that
1. After integrating blisk and scb a weight reduction of 100 kg from 1250 level of 2011 has occurred with improvements in thrust but exact figure of thrust not in public domain.
2. Kaveri snecma lead to engine of f414 INS6 level with a tweaking later with better metallurgy to 75/115 kn level .
One other such source is
3. USA agree to full know how of F414 INS6 110 kn engine but want to retain IP .
But not seen these type of inference from other source . Rest of my post based on study of reliable media report / official news / papers from drdo scientists/ inference from recent tender etc etc .

 

[Scrutator]

No such report in media /net . One guy self claim to be closer to project has said that
1. After integrating blisk and scb a weight reduction of 100 kg from 1250 level of 2011 has occurred with improvements in thrust but exact figure of thrust not in public domain.
2. Kaveri snecma lead to engine of f414 INS6 level with a tweaking later with better metallurgy to 75/115 kn level .
One other such source is
3. USA agree to full know how of F414 INS6 110 kn engine but want to retain IP .
But not seen these type of inference from other source . Rest of my post based on study of reliable media report / official news / papers from drdo scientists/ inference from recent tender etc etc .

Thanks.

I think the uprated F414 (to 110Kn) is just a concept idea - the project hasn't started as yet, or has it??

 

[HariPrasad-1]

Have they reported any improvement in the thrust output with this high temperature?

I do not know exactly but with new blades they are able to reduce the weight by 100 kg and now Kaveri weighs only 1150 kg compared to 1250 KG earlier.Ability to operate at high temperature would certainly have resulted in high thrust but I do not have any information.