GSLV D3 Launch Failure

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negi
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Re: GSLV D3 Launch Failure

Postby negi » 22 Apr 2010 18:30

Well DDM merely picks up on noise generated from elsewhere , in this case didn't we have self professed missile technology control ayatollahs talking on the lines of conversion of PSLV into an ICBM ? or even the reasons which were put forth by Unkil to pressurise Glavkosmos and eventually slap a ban of 2 years on the latter for going ahead with sale of cryogenic engine to India.

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Re: GSLV D3 Launch Failure

Postby KrishG » 22 Apr 2010 20:49

The idea of using a modified-PSLV as an ICBM, I'm not sure about that possibility.

We have to remember that the second stage of PSLV is powered by Vikas aka evolved Viking-4. The technology transfer of the Viking engine should have occurred under strict clauses barring it or it's derivatives to be used on any missiles/weapons. Although we can agree on the fact that over the years ISRO has been indigenizing the imported Viking technology into Vikas and consolidating the capability it is still considered a modified or indigenized Viking. And the prospect of using technology developed for space applications for weapons program could face severe opposition from within ISRO.

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Re: GSLV D3 Launch Failure

Postby Sanjay M » 23 Apr 2010 02:32

babu-slapping ensues:

http://www.zeenews.com/news621302.html

"3% NASA budget? Make it 300% NASA budget! Vee vaant wacuum teshting phor da hooman shpace-flite onlee!"

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Re: GSLV D3 Launch Failure

Postby ramana » 23 Apr 2010 07:57

KrishG, The Viking was co-developed. India contributed knowhow to it. And later used it for Vikas. So no string/wing.

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Re: GSLV D3 Launch Failure

Postby Gagan » 23 Apr 2010 08:10

Well I have heard this PSLV=Surya thing about a decade back.

It was supposedly as told to me a samson option that India had.

But having been enlightened after being in BRFata, several of the premises that this was based on have turned out to be simply not true.

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Re: GSLV D3 Launch Failure

Postby Gagan » 23 Apr 2010 10:06

Didn't APJ Abdul Kalam make that 3rd stage rocket motor for the Ariane-2 or 3?

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Re: GSLV D3 Launch Failure

Postby symontk » 23 Apr 2010 11:16

yes for Diamant, French CNES

But it was was not used. Then they thought it could be used for SLV-3. But again it was not usable due to few issues. ISRO built another one for SLV-3

PSLV first stage motor is a good candidate for you know what, mother of all :)

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Re: GSLV D3 Launch Failure

Postby Gagan » 23 Apr 2010 11:38

With a 2.8 m dia motor, :twisted:
We could have an EyeCeeBeeEmm like this!

Image

:P

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Re: GSLV D3 Launch Failure

Postby SSridhar » 23 Apr 2010 11:43

Gagan, too good. :rotfl:

But,let's be back to thread topic.

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Re: GSLV D3 Launch Failure

Postby Sanku » 23 Apr 2010 12:38

Sanjay M wrote:babu-slapping ensues:

http://www.zeenews.com/news621302.html

"3% NASA budget? Make it 300% NASA budget! Vee vaant wacuum teshting phor da hooman shpace-flite onlee!"


I likes it!!!

Must read for all BRFiets to understand how India works.

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Re: GSLV D3 Launch Failure

Postby Neela » 23 Apr 2010 13:25

Dunno why but the "Surya" has come to be this mythical missile . The name has been in the press for what ...10 years?
No one knows if it exists. No one knows if there is even a project.
See this: http://en.wikipedia.org/wiki/Surya_missile . Speculation onlee.

But what everyone likes is to imagine it to be the most devastating thing mankind has ever known. The name "Surya" also adds to the mystery/awe.
In a way, it has helped. While people keep looking expectantly at DRDO for Surya, the Agni silently seems to avoided the limelight. :twisted:

Chankian?

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Re: GSLV D3 Launch Failure

Postby KrishG » 23 Apr 2010 15:16

ramana wrote:KrishG, The Viking was co-developed. India contributed knowhow to it. And later used it for Vikas. So no string/wing.


I don't think so. IIRC the Viking family was already being used on Ariane-1 when ISRO expressed it's wish to buy the engines with full technology transfer ie in early 1980s.

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Re: GSLV D3 Launch Failure

Postby Varoon Shekhar » 23 Apr 2010 18:04

There were several articles in The Hindu and Business India, about Indians giving large amounts of 'man-hours' for the Viking engine, and also developing and selling a component called pressure transducer, in order to pay for the technology exposure. Maybe some blueprints were also obtained. So Ramana is probably correct. It is pretty certain that no cash was paid.

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Re: GSLV D3 Launch Failure

Postby SSridhar » 23 Apr 2010 19:02

Gopal Raj's book gives complete details about the Viking-Vikas saga. We have discussed this here before as well. Satish Dhawan & T.N.Seshan offered over 100 man-years of Indian engineers' efforts at CNES/SEP, France for the development of the engine. This deal happened in 1973. India also supplied thousands of transducers. India was therefore involved in design, engineering and testing. Of course, France already had a liquid engine, Viking-I.

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Re: GSLV D3 Launch Failure

Postby KrishG » 23 Apr 2010 19:40

India did supply the PTUs for the Viking beginning 1975-76 and contributed in Viking's development but that wouldn't give India a full intellectual copyright on the engine.

My point here is not that India didn't contribute to the development of Viking but that the Vikas probably cannot be used in our weapons program.

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Re: GSLV D3 Launch Failure

Postby Kanson » 23 Apr 2010 20:54

Dr. APJ Abdul Kalam, Principal Scientific Adviser to the Prime Minister, was quoted in the Hindustan Times on 18 September 2000 as saying that "All technologies and industrial complexes are available for an ICBM. It'll not take much time, should India decide on it." He discounted speculation that the ICBM will be the derivative of the GSLV, India's latest space launch vehicle. "Cryogenic engines (used for the GSLV) are good for satellite launch vehicles, not missiles. They require huge fuelling facilities, which can be detected by satellite."

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Re: GSLV D3 Launch Failure

Postby Kanson » 23 Apr 2010 21:06

On Vikas & Cryo............

http://www.thaindian.com/newsportal/sci ... 26418.html

It may seem odd but Nambi Narayanan who introduced the liquid fuel rocket technology in India was ignored not only by the media but also by the Indian Space Research Organisation (ISRO) that he served for over three decades.

In the early 1970s while A.P.J. Abdul Kalam’s team worked on solid motors — that have uses in military missiles — Narayanan was the one who foresaw the need for liquid fuelled engines for ISRO’s future civilian space programmes.

Starting from scratch — and encouraged by then ISRO chairman Satish Dhawan and his successor U.R. Rao — Narayanan worked on liquid propellant motors, first building and successfully testing a 600-kg thrust engine in the mid-1970s and moving on to bigger engines.

After nearly two decades of work and with assistance from France he led his team to develop the Vikas engine used today by all ISRO rockets including the Polar Satellite Launch Vehicle (PSLV) that took Chandrayaan-1 to the moon on Oct 22, 2008.

..............

While the nation cheered Chandrayaan-1 and the government showered awards on several ISRO scientists, Narayanan’s contribution was not mentioned even in passing by ISRO whose future projects to put a man in orbit, or land on the moon, rely on the liquid engines that Narayanan helped develop.

“I am very happy Chandrayaan-1 is a success,” the unassuming scientist told IANS, displaying no grudge against ISRO despite being sidelined. “I am only sad that not one senior ISRO official acknowledged in public my contribution to the moon mission.”

Narayanan will be happy to know that in private, however, his work is recognised within the ISRO community including its current chairman Madhavan Nair. “It was Nambi (Narayanan) who got the liquid propulsion test facility established (in Mahendragiri) and he indeed played a key role in Vikas engines used in our rockets,” Nair told IANS.

ISRO sources admit Narayanan would have been projected as one of the heroes of Chandrayaan-1 had he not been falsely accused as a spy by the Kerala police in November 1994 leading to his suspension from his job as head of ISRO’s liquid propulsion centre and director of the just launched indigenous cryogenic engine project.

The charges were dismissed as phony by the Central Bureau of Investigation in May 1996 and by the Supreme Court in April 1998. The National Human Rights Commission (NHRC) in September 1999 passed strictures against the government of Kerala for having “tarnished (Narayanan’s) long and distinguished career in space research apart from the physical and mental torture to which he and his family were subjected.”

Narayanan, who spent 50 days in jail “for a crime I did not commit”, says his main complaint against ISRO is that it dropped him like a hot potato instead of coming to his rescue.

“It is unfair to say that,” Madhavan Nair told IANS. “No organisation would have supported Narayanan like ISRO did.”

Krishnaswamy Kasturirangan, who was ISRO chairman when Narayanan was arrested, said ISRO could not interfere in a legal matter. “Once the court cleared Narayanan I reinstated him,” he said.

But Narayanan says he was given a desk job and not allowed to return to his work on indigenous cryogenic engine till his retirement in 2001. “By doing so the work on this project got delayed by at least five years,” he says.
Instead of joining his colleagues in celebrating the moon mission, the unsung hero of Chandrayaan-1 is now fighting court cases to get from the state government the Rs.1 million “interim relief” that the NHRC ordered to be paid, and the Rs.10 million in damages he had claimed from the state and central government.

.........

Narayanan says he will get the money sooner or later and that is not important. “All I want is that somebody at the level of ISRO chairman should acknowledge the truth about my contribution to the development of liquid engines with which ISRO is flying (its rockets) today. They should say this in a public forum.”

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Re: GSLV D3 Launch Failure

Postby Gagan » 23 Apr 2010 21:34

The rigours of government jobs in India!

Our family was close to a police officer, who was suspended due to some investigation. I remember as a kid visiting his house with my parents.

The guy was literally in tears. One line I always remember. All his colleagues refused to even speak with him, lest they be also be implicated / investigated or worse! He said things to the effect that while he had helped the careers of several colleagues, those very people refused to even speak with him, leave alone help him!

This fear is very visible in all organizations. We Indians are very vindictive as bosses.

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Re: GSLV D3 Launch Failure

Postby Narad » 24 Apr 2010 01:35

DO we have any recent update on GSLV failure analysis??

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Re: GSLV D3 Launch Failure

Postby dinesha » 05 May 2010 09:37

Cryogenic setback
T.S. SUBRAMANIAN
http://www.flonnet.com/stories/20100521271010100.htm
I....
SRO specialists were sceptical about news reports that claimed the cryogenic engine had ignited for a second but that the turbo-pump that supplied fuel to it had stopped working. The reports quoting an unnamed source also claimed that the rocket’s acceleration had increased for a second before it veered off its path.

A top ISRO engineer was emphatic that there was no ignition at all of the main cryogenic engine. He added: “It is a matter of timing.”

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Re: GSLV D3 Launch Failure

Postby Kailash » 05 May 2010 14:09

“To test the cryogenic propellants on the ground, simulating the vacuum of space and the cold conditions there [space], is a complex job. We can test certain things only in flight. For example, the ignition of the cryogenic engine in the vacuum [of space].” Radhakrishnan asserted that the ignition of the cryogenic engine in vacuum could not be simulated on the ground.


ISRO specialists were sceptical about news reports that claimed the cryogenic engine had ignited for a second but that the turbo-pump that supplied fuel to it had stopped working. The reports quoting an unnamed source also claimed that the rocket’s acceleration had increased for a second before it veered off its path.

A top ISRO engineer was emphatic that there was no ignition at all of the main cryogenic engine. He added: “It is a matter of timing.”

“It hardly matters” whether the engine ignited for one second or more, said Satish. What was important was that the ignition was not sustained. Prima facie, it looked as if the cryogenic engine had not ignited. Ramakrishnan declined to comment on the claim that the engine had ignited for one second. “These are all observations,” he said.


I believe the bolded portion is worrying. Hope they fix the snag successfully before the next launch

ramana
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Re: GSLV D3 Launch Failure

Postby ramana » 05 May 2010 20:30

Wonder why they are blaming 'news reports as if they are independently written? News reports are basd on 'sources'.

The article has lot of fluff and very little to go by. Basically its a complex problem and failure diagnosis will take time and a committee is in place and the good thing is its looking at all things/aspects and not going by early conclusions.

Its irregardless how long and how many times other countries failed for that is not the question now. The question is what happened to GSLV-3? All other matters are page fillers.

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Re: GSLV D3 Launch Failure

Postby Kakarat » 09 Jul 2010 16:49

GSLV-D3 Failure Analysis Report - ISRO

ISRO wrote:The above failure is attributed to the anomalous stopping of Fuel Booster Turbo Pump (FBTP). The start-up of FBTP was normal. It reached a maximum speed of 34,800 rpm and continued to function as predicted after the start of CUS. However, the speed of FBTP started dipping after 0.9 seconds and it stopped within the next 0.6 seconds.

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Re: GSLV D3 Launch Failure

Postby Varoon Shekhar » 09 Jul 2010 17:41

The report seems to suggest that the engine did ignite, after all. This is at variance to what was said in certain quarters earlier. So, good news, relatively speaking!

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Re: GSLV D3 Launch Failure

Postby Sanjay M » 09 Jul 2010 18:16

Could there have been a leak in the gas flow to the turbine? a cutoff in the gas flow to the turbine? major instability in the gas flow to the turbine?

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Re: GSLV D3 Launch Failure

Postby steve » 09 Jul 2010 18:49

Two plausible scenarios have been identified for the failure of FBTP, namely, (a) gripping at one of the seal location and seizure of rotor and (b) rupture of turbine casing caused probably due to excessive pressure rise and thermal stresses. A series of confirmatory ground tests are planned.



Could some body explain me as to what is the meaning of " gripping at one of the seal location and seizure of rotor ".

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Re: GSLV D3 Launch Failure

Postby Vivek K » 09 Jul 2010 19:09

Isn't the turbo pump one of the most basic of techs for space launch vehicles? These were first used in V-2 rockets, correct?

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Re: GSLV D3 Launch Failure

Postby KrishG » 09 Jul 2010 19:57

Sanjay M wrote:Could there have been a leak in the gas flow to the turbine? a cutoff in the gas flow to the turbine? major instability in the gas flow to the turbine?


IMHO it cannot be a case of gas leakage to the turbine. If that was the case then the Oxidizer pump should also have stopped working as both the Fuel Pump and Oxidizer pump are powered by the same turbine.

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Re: GSLV D3 Launch Failure

Postby ramana » 09 Jul 2010 20:14

steve wrote:
Two plausible scenarios have been identified for the failure of FBTP, namely, (a) gripping at one of the seal location and seizure of rotor and (b) rupture of turbine casing caused probably due to excessive pressure rise and thermal stresses. A series of confirmatory ground tests are planned.



Could some body explain me as to what is the meaning of " gripping at one of the seal location and seizure of rotor ".


Could mean the bearing seized up. A tribological failure.

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Re: GSLV D3 Launch Failure

Postby Surya » 09 Jul 2010 20:36

Gagan


off topic but is there a site or way to chart all my travel in the last few months on a globe.

Just want to see how crazy it looks

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Re: GSLV D3 Launch Failure

Postby Gagan » 09 Jul 2010 20:52

You can make google earth placemarks and set it to auto play, and the globe will fly to those places one by one.
Or you can send me your itenarary and I can make placemarks etc and send you the file.

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Re: GSLV D3 Launch Failure

Postby Surya » 09 Jul 2010 20:59

thanks gagan

let me try first

whats your email id - as backup

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Re: GSLV D3 Launch Failure

Postby Gagan » 09 Jul 2010 21:00

:idea:
Merely increasing my post count
Last edited by Gagan on 09 Jul 2010 21:25, edited 2 times in total.

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Re: GSLV D3 Launch Failure

Postby Arunkumar » 09 Jul 2010 21:04

From this link regarding the working of Space shuttle cryogenic Engine

http://www.enginehistory.org/SSME/SSME3.pdf
When the cold LH2 begins to flow into the thrust chamber nozzle, the hardware latent heat causes the hydrogen to expand rapidly, creating a
flow blockage and momentary flow reversal. The result is a pulsating fuel flow rate with an unstable pressure oscillation at a frequency of approximately 2 Hz.


Isro release also states the non-availability of liquid hydrogen (LH2) supply to the thrust chamber of the Main Engine. But the reason attributed is the stoppage of Fuel Booster Turbo Pump (FBTP).

seems to be a modelling\simulation issue where isro would need more data regarding behaviour of cryogenic parts e.g timing of opening\closing of valves etc .

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Re: GSLV D3 Launch Failure

Postby Sridhar » 09 Jul 2010 21:13

What is unclear from the report is whether it was a design issue (where something that would have performed well on the ground would not in the flight conditions due to some unanticipated issue) or whether it was a quality control issue (where the design was fine but something failed in this particular flight). I guess we will know more after they do testing on the ground based on the FAC's analysis.

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Re: GSLV D3 Launch Failure

Postby shynee » 10 Jul 2010 01:54

If you want to calculate the distance you traveled, use TripIt. It's integrated with LinkedIn too.

Surya wrote:Gagan


off topic but is there a site or way to chart all my travel in the last few months on a globe.

Just want to see how crazy it looks

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Re: GSLV D3 Launch Failure

Postby Sanjay M » 10 Jul 2010 05:03

x-posted

Neela wrote:Inferences from the above report and comparing that with previous discussions on this thread:

1. The two vernier thrusters functioned normally.
2. There seems to be no problems related to vacuum conditions

Both the possible causes lead to the turbo pump.
From Wiki: http://en.wikipedia.org/wiki/Turbopump

Turbopumps in rockets are important and problematic enough that launch vehicles using one have been caustically described as a 'turbopump with a rocket attached'- up to 55% of the total cost has been ascribed to this area.

Common problems include:

1. excessive flow from the high pressure rim back to the low pressure inlet along the gap between the casing of the pump and the rotor
2. excessive recirculation of the fluid at inlet
3. excessive vortexing of the fluid as it leaves the casing of the pump

In addition, the precise shape of the rotor itself is critical.

Since ISRO makes no mention of points 2 and 3 above, the basic design is working as designed.

Sanjay , from the report , it says : Fuel Booster Pump stopped after 0.9 seconds. THat means CUS engine got the fuel for that time which translates to 2.2 seconds of flight with the CUS engine! sucess onlee


"itsh a shuccshesh! shabash!" :P

Regardless of what the nature of the turbopump overload was - mechanical, thermal - perhaps ISRO could improve the design for next time, by having 2 turbopumps to take the load of 1.
If you distribute the load, then there is less chance of overload.

Space Shuttle Main Engine, considered to be the most efficient cryogenic rocket engine in existence, uses dual turbo-pumps instead of just having the one. Of these 2 pumps, one is specialized for low-pressure conditions and the other specialized for high-pressure conditions (see LPFTP and HPFTP):

http://en.wikipedia.org/wiki/Space_Shut ... uel_system

Why gamble the whole damn rocket and payload on the one component which suffers the most stress during the launch, when you could pay a bit more and have 2 of them?

Yes, the turbopump is the most critical and most expensive component of the entire rocket, as your quote from wikipedia points out. But distributing the load across multiple turbopumps would then reduce the strain, and potentially simplify the design of each one, making each cheaper, while distributing the risk and reducing the likelihood of failure.

Besides, learning to make multi-pump designs would also pave the way for ISRO building much heavier lifting rockets. After all, when the turbopump is basically expected to shoulder the load for hauling the entire vehicle to orbit, there's no way to just scale up the engine and expect the turbopump to be a superman, withstanding ever greater stress. For really hardy rockets, you have to distribute the load across more than one pump, so ISRO might as well start now.

If they learn the right lessons from this failure -- oh, ekshkuze me, shuccshesh -- then they could revise their design methodology in the right direction, to reach greater heights of achievement.
Last edited by Sanjay M on 10 Jul 2010 05:22, edited 1 time in total.

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Re: GSLV D3 Launch Failure

Postby negi » 10 Jul 2010 05:15

Sanjay M wrote:Regardless of what the nature of the turbopump overload was - mechanical, thermal - perhaps ISRO could improve the design for next time, by having 2 turbopumps to take the load of 1.
If you distribute the load, then there is less chance of overload.

Sanjay while I am no mechanical Engg but I can easily say that one cannot achieve same 'mass flow' rate of a turbine running at a given RPM 'X' by running two turbines in series each with a lower RPM than the original as turbines extract energy from from fluid/gas that drives them and if you are hinting at independent turbines for oxidizer and fuel (i.e. parallel operation) then again you would require a much more powerful pre-burner than the present one to drive each turbine which might not be possible unless you again have another pre-burner to drive a turbine to boost the main pre-burner's performance.Also the sheer size difference between CUS and SSME and the amount of fuel-oxidizer they are required to pump might be a critical factor in making those design considerations .
Last edited by negi on 10 Jul 2010 05:29, edited 1 time in total.

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Re: GSLV D3 Launch Failure

Postby Arunkumar » 10 Jul 2010 05:28

IIRC the reason most Russian Rackit engines(RD-191,RD-180) use a single turbo pump mechanism is because having one instead of two also decreases the chances of failure. I mean there are lesser number of bearing, seals, shaft, valves etc etc to worry about. Also it allows a more compact layout of the engine. So if one wants to cluster multiple engines , as seen in the 100 ton lift vehicle ppt it can be easily done.

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Re: GSLV D3 Launch Failure

Postby Sanjay M » 10 Jul 2010 06:23

SpaceX's Falcon rockets use the Merlin engine, which has a turbopump with dual impellers:

http://en.wikipedia.org/wiki/Merlin_(rocket_engine)

Propellants are fed via a single shaft, dual impeller turbo-pump. The turbo-pump also provides high pressure kerosene for the hydraulic actuators, which then recycles into the low pressure inlet. This eliminates the need for a separate hydraulic power system and means that thrust vector control failure by running out of hydraulic fluid is not possible. A third use of the turbo-pump is to provide power to pivot the turbine exhaust nozzle for roll control purposes.


Dual impellers can then reduce the stresses on the blades, since there are more of them to take the load. If turbopumps suffer mechanical failure, it's more likely at the blades than at the shaft, which is the more solid part of the device.

The turbopump should be overdesigned, since it's the most vital piece of hardware on the rocket, and the one being subjected to the most stress.


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