Author Topic: " A New Heavy-Lift Capability for Space Exploration: NASA's Ares V Cargo Launch Vehicle"  (Read 19000 times)

Offline Generic Username

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 962
    • Aerospace Projects Review
  • Liked: 30
  • Likes Given: 0
http://ntrs.nasa.gov/search.jsp?R=454952&id=2&qs=No%3D120%26Ne%3D26%26N%3D277

"The National Aeronautics and Space Administration (NASA) is developing new launch systems and preparing to retire the Space Shuttle by 2010, as directed in the United States (U.S.) Vision for Space Exploration. The Ares I Crew Launch Vehicle (CLV) and the Ares V heavy-lift Cargo Launch Vehicle (CaLV) systems will build upon proven, reliable hardware derived from the Apollo-Saturn and Space Shuttle programs to deliver safe, reliable, affordable space transportation solutions. This approach leverages existing aerospace talent and a unique infrastructure, as well as legacy knowledge gained from nearly 50 years' experience developing space hardware. Early next decade, the Ares I will launch the new Orion Crew Exploration Vehicle (CEV) to the International Space Station (ISS) or to low-Earth orbit for trips to the Moon and, ultimately, Mars. Late next decade, the Ares V's Earth Departure Stage will carry larger payloads such as the lunar lander into orbit, and the Crew Exploration Vehicle will dock with it for missions to the Moon, where astronauts will explore new territories and conduct science and technology experiments. Both Ares I and Ares V are being designed to support longer future trips to Mars. The Exploration Launch Projects Office is designing, developing, testing, and evaluating both launch vehicle systems in partnership with other NASA Centers, Government agencies, and industry contractors. This paper provides top-level information regarding the genesis and evolution of the baseline configuration for the Ares V heavy-lift system. It also discusses riskbased, management strategies, such as building on powerful hardware and promoting common features between the Ares I and Ares V systems to reduce technical, schedule, and cost risks, as well as development and operations costs. Finally, it summarizes several notable accomplishments since October 2005, when the Exploration Launch Projects effort officially kicked off, and looks ahead at work planned for 2007 and beyond."

PDF downloadable here:
http://hdl.handle.net/2060/20070032980
"US Spacecraft Projects" and "US Launch Vehicle Projects"
aerospaceprojectsreview.com

Offline simonbp

  • Science Guy
  • Senior Member
  • *****
  • Posts: 7138
  • Liked: 314
  • Likes Given: 183
The "5-around" arrangement of the RS-68B's is interesting; wouldn't its interaction with the SRBs create a net thrust asymmetry?

Simon ;)

Offline CFE

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 722
  • Liked: 1
  • Likes Given: 0
Most interesting part of that document, in my view, is the revelation that J-2X uses a similar injector design to RS-68.  At least that's what I'm getting from the fact that the same subscale injector plate can support both RS-68 and J-2X.

Also interesting is the two-stage improvement program for RS-68: first RS-68A (aimed at improving performance) and RS-68B (chiefly aimed at improving reliability.)
"Black Zones" never stopped NASA from flying the shuttle.

Offline ChrisInAStrangeLand

  • Member
  • Posts: 18
  • Liked: 0
  • Likes Given: 0
Pity they're not looking at new tech like the cool-wall vortex combustion chamber demonstrator they just paid for. Shouldn't take long to testa full size chamber, and Ares I needs to shave every pound that it can get.

Offline madscientist197

  • Regular
  • Full Member
  • ****
  • Posts: 1014
  • Liked: 6
  • Likes Given: 0
Quote
CFE - 29/11/2007  4:51 PM

Most interesting part of that document, in my view, is the revelation that J-2X uses a similar injector design to RS-68.  At least that's what I'm getting from the fact that the same subscale injector plate can support both RS-68 and J-2X.

Also interesting is the two-stage improvement program for RS-68: first RS-68A (aimed at improving performance) and RS-68B (chiefly aimed at improving reliability.)

It really does beg the question - how similar is the J2X to the J2? Does the RS-68 use some modern equivalent to Rigi-Mesh?
John

Offline JIS

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 1089
  • Liked: 4
  • Likes Given: 0
Quote
simonbp - 29/11/2007  11:49 PM

The "5-around" arrangement of the RS-68B's is interesting; wouldn't its interaction with the SRBs create a net thrust asymmetry?

Simon ;)

I know that some flame interraction was mentioned here before but it's not clear to me whether this effect really exists and whether it is singificant. Anyway, it could affect aerodynamics of the subsonic flight and two outboard engines would also be closer to SRBs than in the center engine config.
'Old age and treachery will overcome youth and skill' - Old Greek experience

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
The center engine of a 'cross' pattern arrangement suffers from constriction of it's exhaust plume by the outer engines.   This reduces its efficiency by a lot.

Conversely though, without a central engine, you get a low pressure region forming above the engine which sucks up some of the exhaust back up onto the vehicle and the engine's mechanicals.   A central engine keeps most of the 'blow-back' between the outer engines from coming back at the vehicle.   Other wise you need extra TPS.

It's tricky striking a good balance either way.

Ross.
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 5362
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 2239
  • Likes Given: 3883

Looks like there'd be room for a sixth engine in there. Possible future upgrade or redundancy? -- Saturn V was originally only supposed to have 4x F-1s -- How did they get around constriction with that arrangement?

"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
This actually is one of the two key reason *why* they went to five engine configurations for both S-IC and S-II.

The other reason was to provide as close to 100% engine-out capability as possible.   It's almost impossible to get full engine-out, but S-IC could still reach a successful orbit if they had a premature F-1 shutdown only ~10-20 seconds into the launch.

Apollo 13's center engine shutdown clearly demonstrated the engine-out capability of the S-II for all the world to witness.

From what I can see though, Ares-V's fifth engine doesn't offer a great deal of engine-out opportunities, and a sixth engine would only increase complexity & cost, lower safety and reduce performance by a handful of tons.   I doubt it will happen.   I also wonder about how close the RS-68 nozzles are getting to the SRB nozzles with a 5-ring arrangement.   There are already concerns about the sonic shock-wave impinging on the RS-68 at SRB ignition because the exhaust chamber will have no separation wall between the Core and the boosters.   Bringing the engines closer to the SRB's wouldn't help to improve things any.

Ross.
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3067
  • Where Be Dragons
  • Liked: 5
  • Likes Given: 3
Also you can throttle the center engine differently from the rim engines and don't have gimbal problems. This gives more total thrust throttle options.

Offline TrueGrit

  • Regular
  • Full Member
  • ***
  • Posts: 345
  • Liked: 10
  • Likes Given: 0
I am not surprised by the move to a radial engine arragement with no center engine.  The problem is one of thermal protection for the center ablative nozzle.  The center engine would have had a greater external thermal enviornment than any of the outsdie ones.  Composite ablative nozzles like RS-68 need to have external insulation to protect the structural layer bond lines from getting too hot.  The higher enviornment of the center engine would result in thicker/heaver external insulation layer, which due to common configuration with the otuer engines was magnitfied 5x.  By arraging the engines radially you can take some weight off the engines.

The radial engine arragement also results in a better feedline arrangement, less differnces between engines, but that's probably a minor concern.

Offline TyMoore

  • Veteran
  • Full Member
  • ****
  • Posts: 478
  • Eureka, CA, USA
  • Liked: 3
  • Likes Given: 1
Frankly I would be more concerned with acoustical loading transients at SRB startup  and during the transition through Max-Q. At both of these times the dynamic load couplings on the vehicle will approach maximum values.

Good point about external insulation: the very hot, brilliantly radiating SRB plumes will dump a lot of thermal energy onto the exterior of all the RS-68 engines. However, if I am not mistaken, I think that the cruciform arrangement of the RS-68 is rotated 45 degrees to the symmetry line connecting the nozzles of the two SRBs so that the SRB's nestle between outboard RS-68 engine cowlings--this actually makes it a slightly more compact arrangement. I'm not sure about gimbal clearences, but I should think that there would be enough room. One would hope anyway!

If the nozzles are flush to the same plane then transverse radiant coupling between engines will be minimized--ditto for the acoustical loadings. But still, fearsome energies will be unleashed under this vehicle--and recirculating gasses will be almost impossible to eliminate so allowances will have to be made to provide adequate thermal shielding for all structures and machinery exposed to it.


Offline TrueGrit

  • Regular
  • Full Member
  • ***
  • Posts: 345
  • Liked: 10
  • Likes Given: 0
I think Delta IV is any indication I expect a lot of burning around the baseplate, center engine or no center engine.  Fundamental cause of the Delta IV burning is the relatively low velocity GG/turbine exhausts.  These have a lot of unbruned hydrogen, GG runs at a very low MR, and the burning is the exces hydrogen being caughtup in the recirc zone.  I would expect Ares V to be similar.  Delta IV of course uses cork insulation to protect the thermal shield, and I would expect something similar for Ares V.  There's also some sprayon insulating material instead of cork, or could go with a carbon-carbon/matalic thermal shield but weight and cost concerns need to be traded.

Offline MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 5362
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 2239
  • Likes Given: 3883

Might there be room for a J-2X as a sixth engine? Not much good for low altitude Isp, but this would improve markedly once past SRB seperation -- I was thinking in terms of a slight liftoff thrust increase, but a much better boost for later in the ascent. How much would the nominal burn time for the corestage now be, or would the corestage have to be stretched a smidgin to compensate? OR: would an expanded or 2-engined EDS more than compensate? 

"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Offline TrueGrit

  • Regular
  • Full Member
  • ***
  • Posts: 345
  • Liked: 10
  • Likes Given: 0
Another 8 or so thousand pounds isn't worth the performance gained...  You also have a problem of the J-2 not being shaken apart when surrounded by 5 RS-68s.  In general you don't want to mix apples-and-oranges because they are sensative to different dynamic frequencies.  It would require a lot to clear the J-2 to the high vibration signature from the RS-68...  Anyway the more benficial change anyway is to add the J-2 to the EDS.

Offline luke strawwalker

  • Regular
  • Full Member
  • ****
  • Posts: 1032
  • Liked: 9
  • Likes Given: 0
Quote
kraisee - 1/12/2007  2:03 AM

The center engine of a 'cross' pattern arrangement suffers from constriction of it's exhaust plume by the outer engines.   This reduces its efficiency by a lot.

Conversely though, without a central engine, you get a low pressure region forming above the engine which sucks up some of the exhaust back up onto the vehicle and the engine's mechanicals.   A central engine keeps most of the 'blow-back' between the outer engines from coming back at the vehicle.   Other wise you need extra TPS.

It's tricky striking a good balance either way.

Ross.

This 'Five around' configuration looks something similar to a Proton (lot bigger of course).  How does the Proton handle this flame impingement on the vehicle base??  Interesting.  This five around arrangement would also put 2 RS-68's much closer to the SRB's and their exhaust plumes, so how would they interact??  Some interesting CFD work here I bet... OL JR :)
NO plan IS the plan...

"His plan had no goals, no timeline, and no budgetary guidelines. Just maybe's, pretty speeches, and smokescreens."

Offline clongton

  • Expert
  • Senior Member
  • *****
  • Posts: 12053
  • Connecticut
    • Direct Launcher
  • Liked: 7348
  • Likes Given: 3749
Quote
luke strawwalker - 7/12/2007  10:28 AM

Quote
kraisee - 1/12/2007  2:03 AM

The center engine of a 'cross' pattern arrangement suffers from constriction of it's exhaust plume by the outer engines.   This reduces its efficiency by a lot.

Conversely though, without a central engine, you get a low pressure region forming above the engine which sucks up some of the exhaust back up onto the vehicle and the engine's mechanicals.   A central engine keeps most of the 'blow-back' between the outer engines from coming back at the vehicle.   Other wise you need extra TPS.

It's tricky striking a good balance either way.

Ross.

This 'Five around' configuration looks something similar to a Proton (lot bigger of course).  How does the Proton handle this flame impingement on the vehicle base??  Interesting.  This five around arrangement would also put 2 RS-68's much closer to the SRB's and their exhaust plumes, so how would they interact??  Some interesting CFD work here I bet... OL JR :)
Luke,
When we were doing the detail design study tradeoffs for the DIRECT Family, this is what we arrived at for the 5-Engine core of a J-25X launch vehicle. One of the things we spent a lot of time on was arranging the engines to minimize the negative affects of engine exhaust plumes impinging on each other, including from the SRBs. Note that the outer 4 RS-68’s are not at 90 degrees from each other, but at 75 degrees. This tradeoff created a reasonable balance between the RS-68’s and the SRBs.

If there are side boosters of any kind on this new vehicle, I don’t see how they can avoid the negative affects of the booster exhaust if the core engines are in a ring. That’s why we stayed with the center engine.

FWIW
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Offline luke strawwalker

  • Regular
  • Full Member
  • ****
  • Posts: 1032
  • Liked: 9
  • Likes Given: 0
Thanks!  I saw this before but just was wondering if there was anything new or 'deeper' detail about this ring-engine configuration.  The 75 degree angle, moving the engines to a RECTANGULAR configuration with the center engine, thereby balancing whatever impingement effects/interactions between the adjoining RS-68 on one side and the adjoining SRB on the other side of a given engine in the outer 'box' makes good sense.  Even with the 75 degree angle the vehicle still maintains axial symmetry.  With the 'ring' engine configuration using an odd number of engines, there will be three RS-68's on one side of the centerline between the 2 SRB's and 2 engines on the other side of that centerline.  Additionally, those two engines closest to the SRB's would be significantly closer than they would be with a 75 degree rectangular arrangement as you proposed.  The perpendicular centerline would be symmetrical.  Once the SRB's are gone, the core has a pentagon arrangement of engines firing, so from the axial centerline all engines are equidistant.   But while the SRB's are still there, having 3 engines on one side of the centerline between SRB's and 2 on the other would create an imbalance wouldn't it??  Plus I would bet that the plume interaction would rob efficiency from the RS-86's closest to the SRB's, far more than the 75 degree fully symmetrical arrangement would.

With an even number of engines everything can be symmetrical if you go with a square or hexagonal arrangement....  But with a pentagonal arrangement with a center engine you'd have the same problem....  Not that a 6 engine core is likely or practical...  OL JR :)
NO plan IS the plan...

"His plan had no goals, no timeline, and no budgetary guidelines. Just maybe's, pretty speeches, and smokescreens."

Offline JIS

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 1089
  • Liked: 4
  • Likes Given: 0
Quote
luke strawwalker - 9/12/2007  8:02 AM

But while the SRB's are still there, having 3 engines on one side of the centerline between SRB's and 2 on the other would create an imbalance wouldn't it??

NO. The two engines at one side will produce the same momentum as the three opposite engines. The SRBs won't change it.

Quote
Plus I would bet that the plume interaction would rob efficiency from the RS-86's closest to the SRB's, far more than the 75 degree fully symmetrical arrangement would.

I was hoping somebody explain me alleged effect causing efficiency drop. It's very unclear to me. I would expect as plumes are supersonic, that they interract just with nozzle and are affected just by pressure at nozzle exit plane. The plume flow further down doesn't make any difference. If the expansion ratio and the environment pressure is right the plumes won't even expand any further (if neglecting diffusion).
There could be other effects however (like shock waves from the air flow etc.) Is anybody familiar with this?

The SRB nozzle ratio increase and round engine configuration for Ares V hint that my thoughts are right.
'Old age and treachery will overcome youth and skill' - Old Greek experience

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21451
  • Likes Given: 428
Quote
JIS - 9/12/2007  3:40 AM

Quote
luke strawwalker - 9/12/2007  8:02 AM

But while the SRB's are still there, having 3 engines on one side of the centerline between SRB's and 2 on the other would create an imbalance wouldn't it??

NO. The two engines at one side will produce the same momentum as the three opposite engines. The SRBs won't change it.



incorrect, there is a thrust inbalance

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1