Truncated Biconic Shape versus Orion capsule

gaetanomarano · 2007-01-29 09:15:51

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a possible solution for the Orion's "overweight" is a Truncated Biconic Shape: www.gaetanomarano.it/articles/019orionlight.html

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cIclops · 2007-01-29 10:17:38

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a possible solution for the Orion's "overweight" is a Truncated Biconic Shape: www.gaetanomarano.it/articles/019orionlight.html
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The mass of Orion will be reduced during the DAC process, there are some notes earlier in this topic from Skip Hatfield about solutions to reduce mass.

GCNRevenger · 2007-01-29 10:51:26

No you can't simply cut the edges off the capsule. First of all the edges are required to help slow down the capsule from high reentry speeds. Second, gasses for life support and propellants for RCS engines are bulky, and NASA has already slated to put those tanks around the edges of the capsule.

The "edges" of the capsule are also quite small, and you don't save near as much size as you think by omitting them.

gaetanomarano · 2007-01-29 11:09:50

First of all...

"first of all" ...you've posted only a NASA sketch (that is the "evidence" of... "nothing")
"second of all" ...big aerospace companies with army of expert engineers have already developed similar concepts

...you don't save near as much size as you think by omitting them.

great part of the TBS-Orion weight-saving comes from a (20-25% lighter) 4.5 m. thermal shield
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SpaceNut · 2007-01-29 12:43:33

I dug this up from one of the old CEV threads long before we knew if the capsule or plane would be the direction that we were going at the time.

biconic.cev.l.jpg

Just one of the Biconic designs that were thought of back in July 31, 2005 and I am sure that there are more. Biconic tend to be more like lifting body (plane) of which one side gets a heatshield. The Klipper is also lumped into this category.

Oh by the way you can also lump the x38 as well as the
Crew Return Vehicle as well into biconic.

gaetanomarano · 2007-01-29 17:20:22

...one of the Biconic designs that were thought of back...

from my article: "Truncated Biconic Shape... that resembles, in part, some of the early alternative CEV concepts"

never said to have "invented" the biconic shape... (I've only suggested to use it)

but the difference between my design and the concept you posted (or the Kliper) is that the latter may increase very much (maybe, 2-3 times) the CEV's dimension and weight, while, my version may REDUCE the Orion's weight (around 1-2 mT)

...Biconic tend to be more like lifting body (plane) of which one side gets a heatshield...

only if designed to be a lifting body, but it's not the case of the shape I suggest

...lump the x38 as well...

the X-38 doesn't look like a biconic but it's pretty close to a small shuttle
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RedStreak · 2007-01-29 17:50:06

I dug this up from one of the old CEV threads long before we knew if the capsule or plane would be the direction that we were going at the time.
Just one of the Biconic designs that were thought of back in July 31, 2005 and I am sure that there are more.

I seem to recall this being favored or at least suggested for Mars landers back in the mid-80s for Bush Senior's blatantly rejected space initiative. How does this compare to lifting bodies and capsule designs? Any benefits or cons?

GCNRevenger · 2007-01-29 20:34:04

only if designed to be a lifting body, but it's not the case of the shape I suggest

You have to otherwise you would have to carry a super-thick and heavy shield like the Lunar Soyuz designs, or you'd burn up or have excessive g-forces.

Its all about mass-to-area ratio, if you don't have the right size of heat shield, then you are going to be much harder on the shield you do have, and subject the crew to much more stress.

None of the CEV concepts made by any serious competitor that fit NASA's requirements, zero, is a ballistic sharp-sided capsule.

Again, you need to put fuel/air tanks some place inside the capsules' mold lines. Where if not the edge?

gaetanomarano · 2007-01-30 09:18:27

...otherwise you would have to carry a super-thick and heavy shield...

no, the TBS-Orion thermal shield is only resized to 4.5 m. but not reduced so it's safe exactly like the 5 m. Orion's shield

...then you are going to be much harder on the shield you do have...

no, the Orion's shield is only resized in proportion for a 4.5 m. / 8 mT capsule

None of the CEV concepts made by any serious competitor that fit NASA's requirements, zero, is a ballistic sharp-sided capsule.

NASA can't build two dozens of CEVs, also, they have fear to risk on new designs (that's the main reason of the Apollo-like choice) but that doesn't matter these alternative CEVs are wrong, since all them was designed by aerospace companies and expert engineers

Again, you need to put fuel/air tanks some place inside the capsules' mold lines. Where if not the edge?

where you want ...look at the shapes' comparison image in my article ...in the TBS-Orion only the external shape changes (vs. the standard Orion) not the internal volume
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SpaceNut · 2007-01-30 10:29:05

Do you have a plasma air flow for this shape? I fear that because the side walls are not angle enough that you would experience burn through even if the shield does cover enough of the corner edges.

The launch of this shape would also have a different drag coeffient and load air pressure would need to have the capsule rienforced at the upper corners and at the lower onces as well.

Also side draw back would be by shrinking the diameter you also would need to lengthen the SM, Upper stage tanks which also means redoing the launch tower as well for the rocket then is to tall.

GCNRevenger · 2007-01-30 11:01:52

You can't keep the same sized heat shield with a truncated biconic and have ballistic reentry. The Lunar versions of Soyuz, a capsule of similar shape, were slated to have an extra-thick heat shield for return from higher speeds. I imagine the stress on the crew is much higher too.

but that doesn't matter these alternative CEVs are wrong, since all them was designed by aerospace companies and expert engineers

Do you have any idea how stupid that sounds?

I think its ridiculous, many big-name aerospace companies came up with Soyuz-like capsule arrangements (reentry capsule + mission module + service module), yet they didn't use sharp-sided capsules either for any concept that would meet NASA's needs. None.

The fuel/air tanks on the CEV are not inside the pressure vessel, they are tucked inside the "edge" of the capsule that you want to delete. But I digress, these tanks must go someplace, can't you even look at the picture above and see that the are obviously arranged around the edge you idiot?

SpaceNut · 2007-01-30 11:36:06

The next issue is that by reducing the diameter you will need to reduce the crew size and make the unit taller.

Edit

as supected a few posts ago on heat of retry is answered here:
http://www.bautforum.com/showpost.php?p … tcount=221

gaetanomarano · 2007-01-30 19:53:01

...side walls are not angle enough that you would experience burn through even if the shield does cover enough of the corner edges...

the problem doesn't exist with the (near-cylinder-shape) Soyuz and Shenzhou ...and "my" Orion's shape is much close to Apollo than Soyuz

...would also have a different drag coeffient and load air pressure..

this problem (if exists) is minimal ...also, the final Orion's shape at launch will include the LAS fairing

..you also would need to lengthen the SM, Upper stage tanks...

no, since a lighter Orion needs a lighter SM and a lighter 2nd stage

...redoing the launch tower...

"doing" (its first time) not "redoing" (since the Ares-I launch pad doesn't exist now)
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gaetanomarano · 2007-01-30 20:10:52

...can't keep the same sized heat shield...

look at the shapes' comparison image... the TBS-Orion's shape is just slightly different than a cone ...it's NOT a Soyuz nor a Zond!

The fuel/air tanks on the CEV are not inside the pressure vessel, they are tucked inside the "edge" of the capsule that you want to delete.

the "internal space" I refer to, is not only the pressurized vessel, but "the entire intenal space created by its shape" and that space remains unchanged from the 5 m. cone, so, the fuel/air tanks can be placed where you want without reduce the habitable space for astronauts
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gaetanomarano · 2007-01-30 20:14:14

...reducing the diameter you will need to reduce the crew size...

no, look at the shapes' comparison image... the space really used by astronauts remains unchanged with both shapes
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GCNRevenger · 2007-01-30 22:05:08

the problem doesn't exist with the (near-cylinder-shape) Soyuz and Shenzhou ...and "my" Orion's shape is much close to Apollo than Soyuz

Two lies for the price of one!

Its only not a problem if you reenter straight down, instead of at an angle to reduce G-forces from "turn crew to pancakes" to tolerable with such a small heat shield. And your design is indeed more similar to Soyuz than Apollo.

Having a less conical capsule will require a bigger, sturdier launch escape tower if you have to retain the conical shape like Soyuz does. This will add dead mass. Wasn't your idea supposed to save mass? The heat shield on Orion will only weigh a few thousand kilos at most.

and that space remains unchanged from the 5 m. cone, so, the fuel/air tanks can be placed where you want

What? Thats DELUSIONAL, look at the picture! Your design cuts off the part of the capsule where those tanks go! You even lie with your own picture right in front of everyone!

And if the tanks can't go there, then where will they go?

gaetanomarano · 2007-01-31 05:11:01

...instead of at an angle to reduce G-forces...

your claim needs (at least) years of wind-tunnel's sessions and some real in-space tests (do you have a wind-tunnel in your kitchen?)

...add dead mass...

a ligher capsule needs a lighter LAS

...look at the picture...

right... "look at the picture" ...everyone can judge by himself if the TBS-Orion's outlined space is more or less than a cone

...tanks can't go there, then where will they go...

where you (and NASA) want (bottom, top, sides, edges) since the TBS-Orion's outlined space is the same
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GCNRevenger · 2007-01-31 07:50:28

Uh, no. Descent is always at an angle from high speeds. If you came straight down, you probably wouldn't have enough air between you and the ground to slow down (splat!), and if you did the G-forces would kill the crew. Remember, the atmosphere is only ~100km thick, how fast will a capsule at even a fraction of orbital much less Lunar/Mars transit velocity traverse this tiny distance? Only ballistic missiles are built to do this. Ever hear of the "L/D" ratio thing?

The LAS now needs, in addition to the escape rockets, a thick shroud capable of resisting supersonic air pressure and friction heating, because the capsule is too blunt otherwise, just like Soyuz. This will add mass, counteracting the small reductions in vehicle mass if any. Don't forget that the heat shield must be thicker too, just like "Lunar Soyuz" will need a thicker shield than regular "LEO Soyuz." Are the Russians wrong too?

It is plainly obvious from all NASA drawings released to date that the fuel/air tanks for the capsule are arranged around the edge of the capsule. It is also plainly obvious that your capsule does not have these edges. Ergo, this is so obvious, you are a liar. A bad one at that. Furthermore, since the pressure vessel and the mold lines of your design are almost exactly the same, there is no place to put the tanks. In fact, there isn't even any room for landing air bags or retro rockets!

Here is a more recent and detailed picture, note the red and blue tanks around the edge:
(courtesy cIclops).

gaetanomarano · 2007-02-01 06:40:40

...need a thicker shield...

if you look at my drawing with more attention (or less malice...) you can discover that my TBS-Orion (substantially) is just a 4.5 m. STANDARD capsule with only a small change in the external shape to allow more habitable volume, then it works exactly (or very close) to the 5 m. Orion
however, my design needs years and many wind-tunnel's sessions (nor a few angry posts from you) to know if it HAS any aerodynamic or reentry problem or NOT

...all NASA drawings...

again... you've posted ONLY a further NASA sketch, NOT any evidence of your claims NOR any real vehicle... however, a possible allocation of the new-shape capsule's air/fuel tanks is explained in the first TBS-Orion article's update

GCNRevenger · 2007-02-01 17:35:28

...need a thicker shield...
if you look at my drawing with more attention (or less malice...) you can discover that my TBS-Orion (substantially) is just a 4.5 m. STANDARD capsule with only a small change in the external shape to allow more habitable volume, then it works exactly (or very close) to the 5 m. Orion
however, my design needs years and many wind-tunnel's sessions (nor a few angry posts from you) to know if it HAS any aerodynamic or reentry problem or NOT
...all NASA drawings...
again... you've posted ONLY a further NASA sketch, NOT any evidence of your claims NOR any real vehicle... however, a possible allocation of the new-shape capsule's air/fuel tanks is explained in the first TBS-Orion article's update

Oh here we go again,

Biconic capsules often require thicker heat shields, probably because the sides of the capsule may be exposed to the hot gases of reentry on the sides where a shallow-sided capsule will not. Furthermore, you probably have higher heating across the smaller heat shield, requiring it to be thicker. So, the capsule won't really be lighter.

So you want to make the pressure vessel square? Sharp edges don't hold pressure nearly as well as rounded ones, and your design adds many more edges to worry about. Because they don't hold pressure as well, they have to be thicker and hence heavier.

The blunter tip of the capsule also changes the aerodynamics, increasing drag and decreasing payload mass. This can be helped by putting a "shroud" over the capsule much like the Soyuz rocket, but this too will add weight plus complicate escape if the LAS is required (block parachutes) or for a pad abort (rapid capsule egress).

You capsule is not a minor change; the alterations to the shape change it from one class of capsule to another entirely, with different emphasis and trade offs. The one similar type of capsule, Soyuz, has fairly well understood parameters. One of these is that it would need a thicker heat shield to survive reentry from trans-Lunar/Martian velocity and may have problems with reentry accuracy.

Your capsule is like Soyuz aerodynamically, Soyuz has these problems, therefore your capsule has these problems. No wind-tunnel testing required.

And the fuel/air tanks, these things take up considerable volume and should not take up space inside the pressure vessel. So where else would they go?. NASA's 3D rendering is absolutely correct about the placement of these tanks, because there is no where else to put them that makes sense.

gaetanomarano · 2007-02-02 08:54:47

...require thicker heat shields, probably because the sides of the capsule may be exposed to the hot gases of reentry...

as you can see from the Soyuz Reentry Module drawing below, despite the capsule is very close to a CYLINDER (not a biconic) its thermal shield is NOT particularly thick NOR particolarly larger/higher than a cone-shaped capsule (look at the point of attack between the shield and the capsule) then, since the (near cylindrical) Soyuz has accomplished 100+ successfull reentries, a biconic capsule doesn't need a much thicker shield or just the same (a little bit thicker) shield already set for the 5 m. direct reentry lunar-Orion

...putting a "shroud" over the capsule...

the LAS will have a small fairing for the top of the Orion... it only needs to be (a little bit) larger (however, the extra-drag is minimal and only in the first 20 km. after lift-off)

...capsule is not a minor change...

my capsule is a concept... only engineers can give us (after hundreds REAL wind-tunnel sessions) a final word about it ("word-based" aerodynamic tests are USELESS)

...similar type of capsule, Soyuz...

my TBS Orion is NOT a Soyuz

...it would need a thicker heat shield to survive reentry from trans-Lunar velocity...

true, it need the same thermal shield tickness already planned for the 5 m. lunar-Orion

...is like Soyuz aerodynamically...

no, it's NOT a Soyuz

...should not take up space inside the pressure vessel...

they are NOT "inside the pressure vessel" but between the pressure vessel and the capsule's external shell (only in a different position vs. a cone-shaped Orion)
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gaetanomarano · 2007-02-04 11:34:25

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>>> updated "Truncated Biconic Shape Orion" article with thermal shield's shapes and a further water/oxygen/fuel tanks' allocation <<<

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#1 2007-01-29 09:15:51

Re: Truncated Biconic Shape versus Orion capsule

#2 2007-01-29 10:17:38

Re: Truncated Biconic Shape versus Orion capsule

#3 2007-01-29 10:51:26

Re: Truncated Biconic Shape versus Orion capsule

#4 2007-01-29 11:09:50

Re: Truncated Biconic Shape versus Orion capsule

#5 2007-01-29 12:43:33

Re: Truncated Biconic Shape versus Orion capsule

#6 2007-01-29 17:20:22

Re: Truncated Biconic Shape versus Orion capsule

#7 2007-01-29 17:50:06

Re: Truncated Biconic Shape versus Orion capsule

#8 2007-01-29 20:34:04

Re: Truncated Biconic Shape versus Orion capsule

#9 2007-01-30 09:18:27

Re: Truncated Biconic Shape versus Orion capsule

#10 2007-01-30 10:29:05

Re: Truncated Biconic Shape versus Orion capsule

#11 2007-01-30 11:01:52

Re: Truncated Biconic Shape versus Orion capsule

#12 2007-01-30 11:36:06

Re: Truncated Biconic Shape versus Orion capsule

#13 2007-01-30 19:53:01

Re: Truncated Biconic Shape versus Orion capsule

#14 2007-01-30 20:10:52

Re: Truncated Biconic Shape versus Orion capsule

#15 2007-01-30 20:14:14

Re: Truncated Biconic Shape versus Orion capsule

#16 2007-01-30 22:05:08

Re: Truncated Biconic Shape versus Orion capsule

#17 2007-01-31 05:11:01

Re: Truncated Biconic Shape versus Orion capsule

#18 2007-01-31 07:50:28

Re: Truncated Biconic Shape versus Orion capsule

#19 2007-02-01 06:40:40

Re: Truncated Biconic Shape versus Orion capsule

#20 2007-02-01 17:35:28

Re: Truncated Biconic Shape versus Orion capsule

#21 2007-02-02 08:54:47

Re: Truncated Biconic Shape versus Orion capsule

#22 2007-02-04 11:34:25

Re: Truncated Biconic Shape versus Orion capsule

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