Kaveri & aero-engine discussion

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JayS
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Re: Kaveri & aero-engine discussion

Postby JayS » 11 Mar 2018 00:52

ramana wrote:JayS, Can you dig up the definitive as tested values for Kaveri so we can compare madhu's calculation?

dry thrust, wet thrust, sfc at both values.
And design goals for same three parameters.

Thanks for taking the trouble.


We know the target values from Brochure. We know range of achieved thrust numbers. Madhu also confirmed the same from the exGTRE director. However I have never seen actual SFC vakues ever mentioned. But we can expect them to be in close range of brochure specs. I would say +-10% range from brochure number would be more than sufficient to cover actual values.

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Re: Kaveri & aero-engine discussion

Postby ramana » 11 Mar 2018 03:28

When can this be integrated with tejas?

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Re: Kaveri & aero-engine discussion

Postby thammu » 12 Mar 2018 09:07

Is this, what SAFRAN's final offer on TOT - "Cable Harness" :rotfl:
Safran to set up unit in Telangana

http://www.thehindu.com/news/cities/Hyderabad/safran-to-set-up-unit-in-telangana/article23036732.ece
Safran Electrical & Power, a global leader in electrical systems in aeronautics, would set up a unit for electrical wiring interconnection systems in Telangana.

The manufacturing facility, to be set up with an investment of ?52 crore in the Special Economic Zone of Hyderabad airport, is expected to create over 250 employment opportunities, said an official release on an MoU the firm and the Telangana government signed on Saturday.

Safran CEO Philippe Petitcolin and Telangana Industries Secretary Jayesh Ranjan signed the MoU in the presence of French Foreign Affairs Minister M.Le Drian, Union Commerce Minister Suresh Prabhu and Telangana IT and Industries Minister K.T. Rama Rao, at the Indo-French Economic Partnership signing ceremony in New Delhi.

“In the next twelve months, Safran Electrical & Power will deliver the first LEAP electric harnesses made in India and destined for the flourishing of narrow-body aircraft market,” the Safran Group said in a separate release. The Hyderabad facility would be an integral part of the Group’s strategy to establish itself in India to serve an “extremely buoyant local market as well as the existing European and American markets”.

Mr. Petitcolin said, “The new facility reasserts our commitment to products made in India and it completes our industrial grid in the region with a new, high performance production site.” Employing more than 13,000 people in 12 countries, Safran Electrical & Power is a part of the EUR 16.5 billion French multinational Safran Group that operates in the aircraft propulsion and equipment, space and defence markets.

The announcement on opening of the factory in India came in the backdrop of the visit of French President Emmanuel Macron. “The factory’s production will also make it possible to meet any potential needs of the programmes in which the Group is involved in, in the region,” the release said.

The State government would be facilitating Safran E&P and its affiliate Safran Electrical & Power India to obtain necessary permissions, registrations, approvals and clearances as per the existing facilities, rules and regulations.

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Re: Kaveri & aero-engine discussion

Postby JayS » 12 Mar 2018 12:03

thammu wrote:Is this, what SAFRAN's final offer on TOT - "Cable Harness" :rotfl:
Safran to set up unit in Telangana

http://www.thehindu.com/news/cities/Hyderabad/safran-to-set-up-unit-in-telangana/article23036732.ece


Offset, not ToT.

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Re: Kaveri & aero-engine discussion

Postby ramana » 12 Mar 2018 22:55

thammu wrote:Is this, what SAFRAN's final offer on TOT - "Cable Harness"
Safran to set up unit in Telangana

http://www.thehindu.com/news/cities/Hyderabad/safran-to-set-up-unit-in-telangana/article23036732.ece
Safran Electrical & Power, a global leader in electrical systems in aeronautics, would set up a unit for electrical wiring interconnection systems in Telangana.

The manufacturing facility, to be set up with an investment of 52 crore in the Special Economic Zone of Hyderabad airport, is expected to create over 250 employment opportunities, said an official release on an MoU the firm and the Telangana government signed on Saturday.

Safran CEO Philippe Petitcolin and Telangana Industries Secretary Jayesh Ranjan signed the MoU in the presence of French Foreign Affairs Minister M.Le Drian, Union Commerce Minister Suresh Prabhu and Telangana IT and Industries Minister K.T. Rama Rao, at the Indo-French Economic Partnership signing ceremony in New Delhi.

“In the next twelve months, Safran Electrical & Power will deliver the first LEAP electric harnesses made in India and destined for the flourishing of narrow-body aircraft market,” the Safran Group said in a separate release. The Hyderabad facility would be an integral part of the Group’s strategy to establish itself in India to serve an “extremely buoyant local market as well as the existing European and American markets”.

......

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Re: Kaveri & aero-engine discussion

Postby JayS » 12 Mar 2018 23:47

Some interesting read from a GTRE paper
http://proceedings.asmedigitalcollectio ... id=1646704

The Hot End Technologies Directorate (HETD) of Gas Turbine Research Establishment (GTRE) has the mandate to design, development and delivery of airworthy combustor and afterburner modules for a military aero gas turbine engine. In order to meet the mandate, the directorate takes the overall responsibility of design to manufacture of the combustion systems. This paper addresses the challenges faced in the development of combustor module. A short annular combustor with air blast atomizer is incorporated in the engine and it is a very important equipment of a gas turbine engine, wherein the heat energy is added to get Turbine Inlet Temperature (TET). It comprises of a pre-diffuser, a dump diffuser, outer annulus, inner annulus and a flame tube. There has been a basic liner, which was used in earlier engines and there was a shortfall in terms of performance parameters — allowable profile and pattern factors. To improve the performance, in collaboration with the M/s Central Institute of Aviation Motors (CIAM), Moscow, Russia, the liner was redesigned [1]. The secondary holes were totally blocked, primary and dilution holes were altered and it was incorporated with a new dome with a modified curvature. A new air blast atomizer with a swirler having an outer and inner pintle was incorporated. The basic liner was incorporated with these modifications and making this dome out of the high temperature resistance nickel chromium alloy was challenging and it was realized. The liner assemblies incorporating all the welding details have been realized within the GTRE. The combustor system was tested for ground light up to 4.3 km. The light up time was of the order of 5 s. The pressure loss was of the order of 4.9% at a combustor inlet Mn of 0.30. The circumferential and radial pattern factor for the modified liner is of 0.36 and 0.14 respectively.

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Re: Kaveri & aero-engine discussion

Postby JayS » 13 Mar 2018 00:35

If anyone is interested, this paper from GTRE personnel lists all necessary ground tests for a GT engine. Quite a long list. Some of the items themselves are a significant test efforts on their own.

https://www.researchgate.net/publicatio ... ine_Engine

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Re: Kaveri & aero-engine discussion

Postby ramana » 13 Mar 2018 04:00

JayS, I heard on Bloomberg radio today that Rolls Royce engines on Boeing 787 Dreamliner are requiring major maintenance before scheduled time. The airlines that reported it are virgin Atlantic and a Japanese airline AoA (?).
The commentator was saying to get performance the engines are running hotter and thus closer to margin and hence the frequent breakdown.

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Re: Kaveri & aero-engine discussion

Postby JayS » 13 Mar 2018 12:09

^^
It started right from the early days of the operation of the engines.
https://www.telegraph.co.uk/business/20 ... r-engines/
Air New Zealand is the latest Rolls customer to suffer problems with the Trent 1000 engines on the 787. Japanese airline ANA first reported issues with Trent 100s in the summer of 2016. The problem was thought to relate to blades in the turbine corroding far earlier than expected, resulting in the engines being shut down. A few weeks later Virgin Atlantic said it was had also experienced similar troubles with its Trent 1000 engines.

Both airlines took aircraft out service for urgent maintenance, causing hundreds of flight cancellations.

https://thepointsguy.com/2018/03/rolls- ... e-problem/

Most Boeing 787s are powered by the Rolls-Royce Trent 1000 engine, which has been receiving lots of attention after some serious problems: the turbine blades inside the engines were corroding and cracking at a quick rate. And now, the company is paying for the faulty equipment in a big way.


https://www.flightglobal.com/news/artic ... ws-446528/
The problems have centred on compressor rotor blades, intermediate- and high-pressure turbine blades for the Trent 1000 as well as high-pressure turbine blades for the Trent 900.


https://www.flightglobal.com/news/artic ... oe-445143/
R-R is designing a new IPC blade for Trent 1000 engines in the Package C configuration. The IPC blades came under scrutiny almost 15 months ago after an engine failure on board a Scoot 787-9. Singapore’s Transport Safety investigation Agency found that two other shutdowns on Scoot 787-9s were linked to IPC failures probably caused by material fatigue.

Since 2016, R-R also has been replacing the blades in the IPT module of the Trent 1000 after All Nippon Airways reported a series of engine failures. R-R traced the cause of that problem back to suphidation corrosion cracking.




Both Trent 900 on A380 and Trent 1000 on B787 have issues. Its costing big deal for RR and it will take till 2022 for them to repair all engines already sold for B787.

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Re: Kaveri & aero-engine discussion

Postby Prem » 14 Mar 2018 09:52


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Re: Kaveri & aero-engine discussion

Postby SaiK » 14 Mar 2018 12:13

what news is "theparadox14" ?

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Re: Kaveri & aero-engine discussion

Postby nvishal » 14 Mar 2018 12:21

Macron came and went

Kaveri-safran deal still unclear

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Re: Kaveri & aero-engine discussion

Postby thammu » 14 Mar 2018 13:12

Prem wrote:


The subtitles for the video are here:
Prez Macron is coming for More Rafales and Kaveri Engine Ecosystem.

Results are much better than what we thought earlier for Kaveri engine.

For a half life of present M88 and moving towards 1/3rd of the life, the net trade off

resulting from stable thrust at all different zones is mind boggling.

Confirm stability is now above 100kN and another 1XXkN plus.

India wants both the Engine forms to be available for MII Rafales which French side is saying

NO for higher thrust one but had given ok for 100+kN Engine.

Need a complete redevelopment for spectra new version as the engine thrusts and signature

management will undergo changes.

Part of the problem is the 1XX kN engine will need more air intake as it needs a major modification.

India is open to it saying it wants to make Rafales in India and such changes is fine

for India.

Whereas France is insisting product needs maturity before undergoing such massive production

numbers and that also in India.

There needs more new further research on this version and Rafale.

This can change very well the contours of future fleet capability due to additional

thrust being available.

And still the engine life is comparable to present US engine life (as tested and results

from LCA testing of F-404 which has a reduced life versus advertised life) and better than

Russian Engine life as well.

A informal comment says if the heavy version of Kaveri producing 1XX can be stabilised,

we might soon start replacing few MKIs with in house this engine within next 5 years.

More info on this will be shared after Prez Macron visits to sign ecosystem roadmap.



As is evident, the much speculated "Macron Visit Offer" was conditional on buying more Rafales. Hope the government now pours more funds and gets the Kaveri program accelerated "by Indians for Indians".

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Re: Kaveri & aero-engine discussion

Postby Yagnasri » 14 Mar 2018 14:02

mango question - What does this mean? Are we looking at Kaaveri version eng for LCA Mk2 or Mk1A?

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Re: Kaveri & aero-engine discussion

Postby shiv » 14 Mar 2018 14:16

Yagnasri wrote:mango question - What does this mean? Are we looking at Kaaveri version eng for LCA Mk2 or Mk1A?

I would dismiss that report as rubbish. Just grabbing eyeballs and torturing the ears with that idiotic synthesized voice with and idiotic accent "Kay-vry" engine? wtf?

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Re: Kaveri & aero-engine discussion

Postby pankajs » 14 Mar 2018 15:01

/OT

The voice is generated using Text-to-Speech software. I myself use TTS software to listen to e-books while I am doing routine house chores. You could type in a sentence or a para or a story and have it read aloud or create a sound file.

There are a lot of *experts* these days who create videos on various subjects and post them on youtube. To get a wider acceptance for their work they do a voice over using digital Sam or Anne rather than use their own voice i.e of Sampath or Anindita.

These are garden variety experts who have read an article or two or wikipeida and add their own spin to the recent news. Most of these videos are cringe worthy. The moment I hear these digital voices I skip.

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Re: Kaveri & aero-engine discussion

Postby shiv » 14 Mar 2018 18:03

Yeah in fact my own article about the Tejas has appeared on that same site with that same idiotic synthesized voice - probably freeware. Better ones are available for payment

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Re: Kaveri & aero-engine discussion

Postby Mukesh.Kumar » 14 Mar 2018 18:06

Shout Out:

I am going to a seminar on the future of teh Aviation industry held by Boeing today evening. Are there any questions that guru's recommend I ask?
Please reply quoting this post.

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Re: Kaveri & aero-engine discussion

Postby madhu » 14 Mar 2018 21:48

guys,

i did the calculation taking Kaveri is mixed flow turbofan engine. i am getting thrust to be less then pure turbofan. this is due to the fact that temp at exhaust is reducing due to mixing.

i did have a close look at some of the picture of Kaveri engine. looks like bypass are flows outside core and cools upper end of A/B pipe and nozzle. can you guys conform me that. if so then my posted calc is good.i will try to calculate the component efficiency and post the graphics (pure turbofan as of now) for our discussion.

i need conformation on the numbers for M88 and type of turbofan engine. can you guys help me that? then we can do some good assessments.

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Re: Kaveri & aero-engine discussion

Postby madhu » 14 Mar 2018 21:52

JayS wrote:I had posted this previously. Read here, some generic details of the physics.
http://etd.iisc.ernet.in/handle/2005/581
http://proceedings.asmedigitalcollectio ... id=1646704

cannot access it. can u upload it in some other location for me (if possible) plz.

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Re: Kaveri & aero-engine discussion

Postby JayS » 15 Mar 2018 10:19

madhu wrote:
JayS wrote:I had posted this previously. Read here, some generic details of the physics.
http://etd.iisc.ernet.in/handle/2005/581
http://proceedings.asmedigitalcollectio ... id=1646704

cannot access it. can u upload it in some other location for me (if possible) plz.


Thesis is freely available. All you had to do it google for it. :)

http://cgpl.iisc.ernet.in/site/Portals/ ... Thesis.pdf

I don't have the paper. But the abstract gives good enough info.

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Re: Kaveri & aero-engine discussion

Postby madhu » 15 Mar 2018 11:01

JayS wrote:Madhu,

When you mentioned 4300cy beforeN I thought you are talking of specifically Kaveri. I have seen one old reference, a paper from someone from GTRE which says the targeted life for Kaveri was 8000hrs. Which is very high. I have been trying to find out what are actual life numbers for Kaveri but I see no references at all. I forgot to ask this q in AI2017, and even now to exGTRE director through you, when you offered earlier.


Have you seen this paper. It says 7000 cycles, the same number I saw in Dr. K’s slides. As per this paper he gets the life to be around 4260 hrs. this is close to minimum life for GT accessory’s ( which is around 4000 hrs) are per the same slide. So I guess we can conclude the life should be some where about 4000 hrs for cold parts.
https://www.researchgate.net/publicatio ... ation_list

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Re: Kaveri & aero-engine discussion

Postby JayS » 15 Mar 2018 11:17

madhu wrote:guys,

i did the calculation taking Kaveri is mixed flow turbofan engine. i am getting thrust to be less then pure turbofan. this is due to the fact that temp at exhaust is reducing due to mixing.

i did have a close look at some of the picture of Kaveri engine. looks like bypass are flows outside core and cools upper end of A/B pipe and nozzle. can you guys conform me that. if so then my posted calc is good.i will try to calculate the component efficiency and post the graphics (pure turbofan as of now) for our discussion.

i need conformation on the numbers for M88 and type of turbofan engine. can you guys help me that? then we can do some good assessments.


That's correct. Bypass mixed with core flow starting just before A/B until almost at the start of nozzle. Without such arrangement, exhaust pipe and nozzle would melt with A/B on.

Almost all mil jets are the same in this repsect.

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Re: Kaveri & aero-engine discussion

Postby madhu » 15 Mar 2018 11:28

JayS wrote: That's correct. Bypass mixed with core flow starting just before A/B until almost at the start of nozzle. Without such arrangement, exhaust pipe and nozzle would melt with A/B on.
Almost all mil jets are the same in this repsect.

if that's the case then the Dry thrust is only 40kN. giving an error of -23%. I feel this is too less.

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Re: Kaveri & aero-engine discussion

Postby JayS » 15 Mar 2018 11:31

madhu wrote:
JayS wrote:Madhu,

When you mentioned 4300cy beforeN I thought you are talking of specifically Kaveri. I have seen one old reference, a paper from someone from GTRE which says the targeted life for Kaveri was 8000hrs. Which is very high. I have been trying to find out what are actual life numbers for Kaveri but I see no references at all. I forgot to ask this q in AI2017, and even now to exGTRE director through you, when you offered earlier.


Have you seen this paper. It says 7000 cycles, the same number I saw in Dr. K’s slides. As per this paper he gets the life to be around 4260 hrs. this is close to minimum life for GT accessory’s ( which is around 4000 hrs) are per the same slide. So I guess we can conclude the life should be some where about 4000 hrs for cold parts.
https://www.researchgate.net/publicatio ... ation_list


Good find. This gives me a starting point to dig in more. We can find more stuff using names and references.

Yes, we can take that life for these parts are 4000hrs. These parts are not life limited parts though. That would be compressor blades for cold section and Turbine blades and discs for hot sector. Lets see if we can find something about them.

Do you know if Kaveri is designed with modular approach that GE F404 had...? It would make sense if they did. But I have not seen a reference to it so far. Didn't ask in AI2017 too.

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Re: Kaveri & aero-engine discussion

Postby JayS » 15 Mar 2018 12:39

http://proceedings.asmedigitalcollectio ... id=1838626

This paper has following statement:

The primary structural design life requirement of 7000 cycles, (with a factor of 2) should have designs made using -3σ strength properties and hot parts shall posses half of the cold parts life. Ensuring engine integrity is a fundamental requirement for certification and subsequent safe service operation of rotating discs.


This paper doesn't include final results, but we know the target at least now.

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Re: Kaveri & aero-engine discussion

Postby madhu » 15 Mar 2018 12:57

JayS wrote:http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1838626

This paper has following statement:

The primary structural design life requirement of 7000 cycles, (with a factor of 2) should have designs made using -3σ strength properties and hot parts shall posses half of the cold parts life. Ensuring engine integrity is a fundamental requirement for certification and subsequent safe service operation of rotating discs.


This paper doesn't include final results, but we know the target at least now.

yes thatz true. fact of 2 b/w cold and hot part and further factor 2 for hot and A/B parts. BTW F404 is also rated to 4000hrs. got from declassified report http://www.dtic.mil/dtic/tr/fulltext/u2/a164562.pdf
so life = 4000hrs ko lock kiya-jaye :wink:

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Re: Kaveri & aero-engine discussion

Postby JayS » 15 Mar 2018 14:35

These numbers for Kaveri are respectable. Would be interesting to know actual certified numbers. In addition blades would have separate life numbers. Any info on HPT nozzle/blade life..? That's the most restricted part in terms of life.

More detailed data on F404 is available on internet. Here is on link for example, I had posted a while back on this thread.
https://calhoun.nps.edu/bitstream/handl ... sAllowed=y

Check table 1.1.

F404 used to have severe issues until early 1990s, reducing life of some of its components up to 60%.

Do you know achieved life numbers for Kaveri..?

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Re: Kaveri & aero-engine discussion

Postby madhu » 15 Mar 2018 19:10

JayS wrote:Do you know achieved life numbers for Kaveri..?

no I do not know.

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Re: Kaveri & aero-engine discussion

Postby madhu » 15 Mar 2018 21:05

here is the calculation for all M88, F404 -400 and Kaveri. i am able to get a good match for M88 but not for F404 and Kaveri. appreciate if some one is interested could redo it just to conform that i have not done any clerical error.

source of inputs are from
http://www.dtic.mil/dtic/tr/fulltext/u2/a164562.pdf
https://www.safran-aircraft-engines.com ... rcraft/m88

following are my observation
a) P02/P06 is below 1. do not know why?
b) not sure of fan thrust.
c) no textbook data to verify calculation unlike pure turbofan :(

Image

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Re: Kaveri & aero-engine discussion

Postby JayS » 16 Mar 2018 11:14

Here is a paper showing GTRE did indeed made some good progress in dealing with Flutter in 1st stage of Fan/Booster/LPC (whatever you want to call it). This paper is from Dec-2017 conference.

Flutter Alleviation by Aeroelastic Tailoring of a Transonic Rotor Blade
http://proceedings.asmedigitalcollectio ... id=2672138

High asynchronous self-excited blade response was observed in a transonic first stage rotor during the evaluation of flutter stability in high forward speed conditions. This candidate baseline rotor stage is a highly loaded, snubber-less bladed-disc configuration mounted in an axial low pressure compressor with tip speed in the order of 400 m/s. During the tests, the high asynchronous blade response was measured by strain gages, tip timing system and unsteady blade pressure transducers, which were correlated with analytical predictions. To alleviate this problem, it was attempted to tailor the first rotor blade configuration alone by adhering to all the constraints such as geometric, aerodynamic matching, material selection and utilising the same dovetail root configuration in the existing disc configuration. While tailoring the rotor blade, the critical blade parameters such as axial chord, thickness to chord, stagger, camber, leading and trailing edge radius were iterated from hub to tip. In the tailored rotor blade, the first flexure mode frequency, 1F was improved by 45% whereas the separation between second flexure, 2F and torsion mode, 1T were improved by over 30% with 4.9% weight penalty. Using the one way fluid-structure interaction approach, the blade incidence variation for different inlet pressure conditions and aerodynamic damping were evaluated using energy method for both the configuration. Blade sets of the tailored configuration were manufactured and tested in a dedicated compressor test facility, where characteristics were generated from 70% to 100% corrected speeds. The rig tests confirmed the predicted compressor performance as well as the improvement of natural frequency using blade mounted strain gages for the tailored blade. Upon the verification in the test rig, the tailored rotor configuration was further fitted in the engine and tested up to 103.3% of its design speed. The blade experienced two different inlet total pressure conditions in the test rig and engine tests. The unsteady pressure transducers and blade tip timing sensors did not show any asynchronous response in the corrected speed range for the tailored configuration. Compared to the baseline rotor blade, this tailored rotor blade demonstrated the absence of asynchronous response in the fundamental flexure mode and also well correlated with the aerodynamic damping prediction by energy method. Using this correlation, it is further analytically demonstrated that the blade will have sufficient aerodynamic damping at higher forward speeds and also minimal incidence variation in these conditions.


Here is a usful link showing flutter regimes for a compressor: http://www.energy.kth.se/compedu/webcom ... ressor.htm

Image
https://goo.gl/images/RdoWG1

1 - subsonic stall flutter
2 - transonic stall flutter
3 - choke flutter
4 - subsonic started flutter at low back pressure
5 - supersonic started flutter at high back pressure
6 - classical flutter

More info in the link.

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Re: Kaveri & aero-engine discussion

Postby Philip » 16 Mar 2018 11:58

On a tangential note, the grounding of 70+ Neo A-320s due to faulty PW engines is severely affecting ops of 2 of our civil airlines.Global failures too .Is there any definitive info as to the nature of the problem and whethere there will be a hangover onto PW's mil engines too.

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Re: Kaveri & aero-engine discussion

Postby madhu » 20 Mar 2018 19:12

JayS wrote: Any info on HPT nozzle/blade life..? That's the most restricted part in terms of life.

Its around 1800 hrs

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Re: Kaveri & aero-engine discussion

Postby Pratyush » 20 Mar 2018 19:47

All this is well and good. But the stingi Bania in me wants to know by when it will be put into the Tejas and sore into the air.

So that I can sleep easy and not worry about the next ***** star the POTUS is going to bang and then deal with its after effects. On Indian air force.

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Re: Kaveri & aero-engine discussion

Postby JayS » 20 Mar 2018 20:16

madhu wrote:
JayS wrote: Any info on HPT nozzle/blade life..? That's the most restricted part in terms of life.

Its around 1800 hrs


Thanks for the info Madhu. I will collate all lifing info and put in in Kavery gyan thread for reference.

BTW, I noticed you are using total Temp in Speec of sound formula. Is that right..? If so, it should be static temp.

Also PR is applied on Static pressure, not total pressure.

You are getting some ridiculously high M2 and V2 on cold exit before mixer. You have P2 greater than P02, which is physically impossible.

I am making my own excel sheet for 1D mean line analysis. But it will take quite a while before I can make it work.

You may find something like this useful. Download link on same page.

https://www.researchgate.net/publicatio ... fan_Engine

madhu
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Re: Kaveri & aero-engine discussion

Postby madhu » 20 Mar 2018 23:47

JayS wrote:
madhu wrote:Its around 1800 hrs


Thanks for the info Madhu. I will collate all lifing info and put in in Kavery gyan thread for reference.

BTW, I noticed you are using total Temp in Speec of sound formula. Is that right..? If so, it should be static temp.

Also PR is applied on Static pressure, not total pressure.

You are getting some ridiculously high M2 and V2 on cold exit before mixer. You have P2 greater than P02, which is physically impossible.

I am making my own excel sheet for 1D mean line analysis. But it will take quite a while before I can make it work.

You may find something like this useful. Download link on same page.

https://www.researchgate.net/publicatio ... fan_Engine


I know there are lot of ridiculously numbers i am getting. Speed of sound is a function of static temperature not stagnation temperature like i have used.
Static Pressure of fan outlet p16 had to be same/slightly better than p6 but in my case its not. Plz dont use my excel as of now. I am still working on mixed flow configuration. As of now my earlier excel one with separate flow is correct. Will see if i get any success will post.

madhu
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Location: India

Re: Kaveri & aero-engine discussion

Postby madhu » 24 Mar 2018 08:58

can any one conform me the turbine inlet temperature of Kaveri and M88 engines?

chetak
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Re: Kaveri & aero-engine discussion

Postby chetak » 24 Mar 2018 09:43

Philip wrote:On a tangential note, the grounding of 70+ Neo A-320s due to faulty PW engines is severely affecting ops of 2 of our civil airlines.Global failures too .Is there any definitive info as to the nature of the problem and whethere there will be a hangover onto PW's mil engines too.


Maybe one needs to look into the news that the maximum numbers of these suspect engines are flying in India.

Are other countries/operators cautious, foolish?? or have we alone thrown all caution to the winds because some jokers have been paid off??

Such aeronautical antics certainly do not bode well for India's already tattered regulatory reputation or even concerns for passenger and flight safety.

JayS
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Re: Kaveri & aero-engine discussion

Postby JayS » 24 Mar 2018 11:51

chetak wrote:
Philip wrote:On a tangential note, the grounding of 70+ Neo A-320s due to faulty PW engines is severely affecting ops of 2 of our civil airlines.Global failures too .Is there any definitive info as to the nature of the problem and whethere there will be a hangover onto PW's mil engines too.


Maybe one needs to look into the news that the maximum numbers of these suspect engines are flying in India.

Are other countries/operators cautious, foolish?? or have we alone thrown all caution to the winds because some jokers have been paid off??

Such aeronautical antics certainly do not bode well for India's already tattered regulatory reputation or even concerns for passenger and flight safety.


viewtopic.php?f=2&t=3986&start=4280#p2259764

prasannasimha
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Re: Kaveri & aero-engine discussion

Postby prasannasimha » 25 Mar 2018 08:05

^^ chetek a faulty engine shutting down was the reason aircraftcwere grounded. There were several incidents both in India and Europe. DGCA rightly grounded the aircraft. Simple question would you like to travel or send your loved ones in a plane with a faulty engine all the more knowing previous incidents with engine shut downs have occurred ? Easy to say one engine shut down and we can manage with the other bit that's not normal and expected ops for any civilian engine. Let's not underestimate our safety requirements. If a plane crashes and people die the same people will question - knowing that there is a faulty engine why did the regulators not take corrective action.The mandate for Pratt and Whitney was to give an engine with a designed MTBF. If is does not match that and there have been repeated flight incidents requiring flight diversion or emergency measures pray tell me why DGCAid wrong.
It's so easy to say it has never happened go any other customer etc etc and I have seen this as a standard response by companies so much so that when I report a faulty device or equipment or suture etc the first thing that I tell them is not to tell me that BS as if I am at fault. I tell that upfront . I also remind them that a US company lost millions of dollars because they neglected an incident which I reported once and they gave that BS answer. Later they were sued for millions list and the guy sheepishly looked downcast compared to his cocky stance when I told him. Always respect the customers genuine concerns and reports or it will come back to bite you. I think we have to stop this sort of self doubt and self flagellation and always think we are possibly wrong. It is not normal to have such frequent engine failures in civilian engines -period. Why do you think P&W are replacing them in the first place if they were so safe ? Or do we want to have the next crash to act. The airline indusrry operates on a near hit miss concrpt for safety. 2 planes coming within 1000 feet of lateral separation is considered as a neart hit miss and analyzed as a crash so why should an engine failure be neglected ? If anything it has made everyone sit up ,notice and act. I repeat woyld you knowingly send your lived ones in such a plane ?


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