Ship Design Philosophy

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Spaceships: Engineering, Chemical Power Plants, and Hydrogen Generators: Safer Solutions for Power Plants

High purity hydrogen is critical to reducing windage friction losses, increasing overall power plant efficiency. Some plants utilize bulk hydrogen while others produce hydrogen with on-site generators. Proton OnSite’s PEM hydrogen generators use only water and electricity, to generate gas on demand, eliminating exposure to hazardous materials and risk of personnel injury. A solid membrane separates the hydrogen and oxygen, ensuring a safe and consistent supply of ultra-high purity hydrogen for industrial use.

https://www.youtube.com/watch?v=5mXa13CUMz0

Imagine if it's water in the tanks, which is practically free compared to my original choice, diesel. Also, would seem to resolve the oxygen problem as well.

What is a Hydrogen Power Plant?
A hydrogen power plant is a concept design for a new widespread source of electricity. Essentially, it is a facility which uses hydrogen to produce electrical energy. It is being proposed that a large facility, not unlike a nuclear power plant in appearance, be constructed in the city of Peterhead, Scotland. Plans were first laid by GE in 2006; however, the logistics of supplying the power plant has delayed its construction. The cost involved with obtaining the hydrogen means that the overall cost of hydrogen-based electricity will be greater than that of current nuclear and petroleum-produced electricity.

How Does a Hydrogen Power Plant Work?
Large tanks of liquid hydrogen will feed into thousands of hydrogen fuel cells. These fuel cells are solid structures containing an electrolyte fluid and two terminals, much like batteries. The reactants flow into the cells, in this case hydrogen and oxygen. They intermingle with the electrolyte to produce an electrical charge and water as a byproduct. The water flows out another port while the electricity is siphoned off the terminals and held in gigantic multi-ton batteries. The electricity resides in the batteries until it is needed, in which case it is sent out through the local power grid just like any other type of power plant. In theory, this could be a near perfect source of energy as it has no dangerous byproducts and is just as fuel-efficient as the average internal combustion engine. The biggest problem is, and always has been, obtaining cheap supplies of hydrogen.

How Will The Hydrogen Be Obtained?
The reason this first hydrogen power plant is to be constructed in Scotland is because it is near the North Sea, where the Sleipner Field is found. This is a massive field of natural gas being worked and refined by the Norwegian company StatoilHydro. Natural gas can be processed into hydrogen with the greatest cost and energy efficiency with about 80% of the potential energy from the natural gas being retained in the form of hydrogen. This is done by a process called steam reforming. The natural gas is cooked at temperatures over 1,000 degrees Celsius and combined with water vapor. The result is hydrogen and carbon dioxide. The hydrogen can be harvested, bottled, and condensed into liquid for easy transport, while the carbon dioxide can be disposed of by re-injecting it back into the natural gas reservoir.

 

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Starships: Engineering, Capacitors and Batteries

I think the basic difference between capacitors and batteries is the accumulation and discharge of energy.

Capacitors need to be able to be charge and discharge the energy required to power the jump drive within a turn, one reason they cost three megaschmuckers per tonne.

Batteries should have a limited performance in this regard, otherwise you might as well substitute them in the jump drive.

At best, batteries cost a hundred kiloschmuckers per tonne at eighty percent capacity of a capacitor, that's twenty four times cheaper.

 

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Starwarships: Hulls and Escort Carriers

I tended to amuse myself by stating that an escort carrier is a propelled steel box, though in my imagination square like.

If you made it triangular, each side would be mutually supporting, and since only volume counts, may be not actually a factor in the efficient us of space onboard.

If you divide it into three parts, the peak could be bridge and accomodations, the middle what I would assume is the launch tube and recovery, and the bottom the hangar and engineering.

 

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Spaceships: Hulls and Why SpaceX ditched lightweight Carbon Composites for Stainless Steel to make a sweaty Starship

SpaceX’s upcoming rocket called Starship Super Heavy formerly known as BFR, will no longer be made out of lightweight Carbon Composites, it’ll sweat a lot, and just MIGHT need a TON of WD-40.

So we’ll take a look at all of Elon’s most recent claims about stainless steel actually being the best option and see if we come to the same conclusion.

We’ll also take a look at some other rockets that are made of stainless steel and explain how SpaceX's use of this material is a little different as they’ll be using new manufacturing techniques and doing things that have never been attempted before.

https://www.youtube.com/watch?v=LogE40_wR9k

1. Stainless steel costs three bucks per kilogramme, which should be three fifths of a Credite Imperiale.

2. Can you cold form crystaliron?

3. Shiny surface resists heat better.

4. Stainless steel sandwich with varying layers optimizing specific performance.

5. Perforated hull; cooling.

6. Double you dee forty.

7. Balloon tank; how thin actually is the standard spaceship hull?

 

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Spaceships: Hulls and Why SpaceX’s Starship will fall like a skydiver and not fly like an airplane

Ever since SpaceX tweeted this photo on September 13th, 2018, a lot of people fear the BFR is slowly turning into the space shuttle. Quoting ever growing wings and a giant heat shield covering the belly of the ship… so how is this any different than the Space Shuttle?


Today we’ll to cover three topics. First, we’ll compare the reentry of the space shuttle to the reentry of the BFS and show how they differ. Then we’ll explain what control surfaces allow the BFS to perform this reentry, and then we’ll compare the thermal protection systems of the Shuttle and the BFS.

https://www.youtube.com/watch?v=SCCw_M8MAU0

I think that the fins while acting as airbrakes during reentry, and orientate the vehicle, they probably could give some form of lift during take off.

The fins are configurable, and it sort of makes the obvious comparison.

 

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Starships: Hulls and Space/balls

61. Configurable fins with embedded solar panelling could be rather useful to catch optimum rays from the sun.

62. They could also second as the landing gear.

63. Failing that, a telescoping tripod arrangement was my preferred choice.

64. I think the tripod legs could orientate themselves to the centre, and radiate outwards, more to stabilize the space/ball on the ground when the lifters are turned off.

65. A purely rocket propulsion would need to align the tripod land gear with the rocket, rather than the deck(s).

 

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Inspiration: Helsreach

https://www.youtube.com/watch?v=1D4jr-0_COg&list=PLSWAxTw0FAGxkkqmuroxMwN5LviaBosJ5
https://www.youtube.com/watch?v=UqUSHhWErdY
https://www.youtube.com/watch?v=SDwxnzHvhdo
https://www.youtube.com/watch?v=yyx-uwWc3_s

Probably one of the best fanmade works out there.

Apparently, it's also one big audition tape, and Games Workshop has commissioned him to do something named Angels of Death, a reference to the Blood Angels.

 

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66. I wonder how much radar, and by extension, lidar, reflection a sphere has, since you assume that except for the point facing said sensor, the beams should start steadily scattering even more along the curvature(s).

67. I understand that the TIE Fighter (the inspiration for the BALL Fighter), has a width of 6.3 metres, which is about the diameter of a space/ball.

 

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Inspiration: X4 Foundations

https://www.youtube.com/watch?v=N6s9sXjqCME

https://www.youtube.com/watch?v=2ZHqid2t7vM

 

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Starships: Hulls and Space/balls

68. The important aspect of most of my design concepts are based on cost effectiveness, based on the current rules set.

69. A lot of computer programmes are expensive (comparatively) for smaller ship designs, and I don't see the option to pirate them.

70. At this point, it probably is cheaper to add more crew, though at the moment this is meant specifically for a cheap smallcraft, than to automate (further).

71. Commercial salaries are fixed in canon, and we know more or less life support costs.

72. With the military, less so, though a gunner is likely going to the equivalent of a private soldier or specialist's salt, which is probably around three to four hundred Credite Imperiale per month (divided by five from current going rates).

73. As I recall from Striker, it costs about base fifty thousand schmuckers per annum per soldier for care and feeding (and training), though cost accounting could probably spread the amount across various aspects of the military bureaucracy.

74. Apparently, it does cost the Pentagon a million bucks per annum per soldier to deploy them in Afghanistan, and I believe the implication is that is the direct cost involved, that includes support.

75. The extra guy could be given his own workstation, basically a double cockpit, where he acts as the weapons officer, or if you have a turret, up in there.

76. Let's be clear, the weapon's officer is there to save cash on having a dedicated fire control programme, which keeps down the cost of the computer as well, and as a second pair of eyes to supplement a rather measly sensor suite.

77. As regards to the military pay grade of either the pilot or weapon's officer, it doesn't necessarily have to be officer rank, but could be just two specialists, with relevant skills of zero.

78. Helicopter pilots have a warrant; smallcraft specialists with pilot one would get promoted to that rank, and probably transferred to a BALL Interceptor squadron.

 

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Starships: Hulls and Ultima Thule Isn't A Snowman Any More

New images just downloaded from New Horizons show that the 2 lobes of MU69 are highly oblate spheroids, which really changes our view of the object, and simultaneously raises questions of formation process while providing clues as to why it's shaped this way.

https://www.youtube.com/watch?v=rD8eVMXfsK4

Elemental class cruiser.

 

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Spaceships: Engineering and Reactionary Rockets

Reactionary rocket

. Factor
.. fifteen
. Technological level
.. eleven
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 30%
. Fuel usage percentage per hour
.. 37.5%

. Factor
.. fifteen
. Technological level
.. fourteen
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 30%
. Fuel usage percentage per hour
.. 15%

. Factor
.. three
. Technological level
.. seven
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 6%
. Fuel usage percentage per hour
.. 7.5%

. Factor
.. three
. Technological level
.. ten
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 6%
. Fuel usage percentage per hour
.. 3%

. Factor
.. six
. Technological level
.. eight
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 12%
. Fuel usage percentage per hour
.. 15%

. Factor
.. six
. Technological level
.. eleven
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 12%
. Fuel usage percentage per hour
.. 6%

. Factor
.. nine
. Technological level
.. nine
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 18%
. Fuel usage percentage per hour
.. 22.5%

. Factor
.. nine
. Technological level
.. twelve
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 18%
. Fuel usage percentage per hour
.. 9%

. Factor
.. twelve
. Technological level
.. ten
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 24%
. Fuel usage percentage per hour
.. 30%

. Factor
.. twelve
. Technological level
.. twelve
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 24%
. Fuel usage percentage per hour
.. 12%

Thrust ten is the odd one out:

. Factor
.. ten
. Technological level
.. ten
.. default
... cost adjustment percentage
.... 0%
. Displacement percentage
.. 10%
. Fuel usage percentage per hour
.. 25%

. Factor
.. ten
. Technological level
.. thirteen
.. high technology
... cost adjustment percentage
.... 50%
. Displacement percentage
.. 10%
. Fuel usage percentage per hour
.. 10%

. Factor
.. ten - nine plus overload drive
. Technological level
.. seven
.. early prototype
... fuel inefficiency
.... 50%
... cost adjustment percentage
.... 1000%
. Displacement percentage
.. 20%
. Fuel usage percentage per hour
.. 37.5%


I think I'm repeating myself, but as regards missiles, I don't think I'd bother giving them more than a half an hour's worth of propulsion, as most of them tend to wander off after this point, so just max out acceleration and shoot within long distance.

 

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Starships: Hulls and Space/balls

79. Ship's locker could and should include a technological level nine eight kilogramme Portable Airlock at a thousand schmuckers.

80. Considering that additional airlocks take up two tonnes (usually) and cost two hundred thousand schmuckers, just cutting a hole in the hull, and putting an airtight hatch on it begins to look appealing.

81.You could semi assemble a technological level ten Habitat Module in the hull, which includes survival rations, battery power, and life support for six occupants for one thousand man hours; weighs in a five hundred kilogrammes and costs twenty thousand schmuckers, though I'd suppose you could find something similar at technological level nine.

82. The other three options are acceleration benches, a four tonne brig, or a four tonne semi-stable.

83. A fresher is going to take up space, water bottles and diapers aren't likely to, though I believe that if you don't need to curtain off the area, a simple wall attachment with some form of negative pressure should work as well.

 

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Inspiration: Mortal Engines

https://www.youtube.com/watch?v=nPeQ_24KnbU

Almost Forty Kayesque, if a hive city combined with an Imperial battleship.

The plot, acting, editing and script suck, despite being ripped off mostly from Bride of Frankenstein and Star Wars, with recognizable elements from other franchises like the Matrix and Mad Max, but just enjoy the special effects.

 

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Spaceships: Engineering, Escape Velocity, and Reactionary Rockets

Well, obviously, you can turbonize the process by adding an appropriately factored rocket, since you'd want a minimum investment in space and cost, as rockets are twice as big as manoeuvre drives, though cost five times cheaper.

Or a high burn thruster, once you get actual performance specifications.

You could have an external rocket booster pack that drops off once you're in orbit, but I'm guessing the service would make quite a dent into operating profit.

A budget factor one variant is relatively very thirsty, at three percent per thrust hour, but if you use it only for a turn, that's 0.3% for presumably a technological level seven example, which may or may not be subject to some form of discount at higher technological level industrial bases.

This assumes a somewhat streamlined hull, not too sure how this works with a brick; I'd expect a planetoid would expect turbulence and quite a number of piloting checks.

 

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Spaceships: Engineering, Escape Velocity, and Reactionary Rockets

Ascent G-Forces

The Apollo 11 AS-506 launcher flight report contains a nice graph of the G-force curve of that famous Saturn V launch:

From this chart you can see that, off the pad, the Saturn V first stage is doing about 1.2g; this climbs rapidly as atmospheric drag falls and fuel mass is consumed. The center engine is intentionally shut down to limit acceleration, and the outboard four keep pushing to a max of about 3.9g. This is the highest acceleration in the mission until re-entry and landing.

The upper stages are less dramatic in their acceleration but follow similar increasing curves; the second stage curve steps down once for the center engine cutoff and once again when the fuel-to-oxidizer ratio is switched ("EMR Shift" on the graph, for Engine Mixture Ratio) -- this is done to optimize Isp in vacuum, with the timing dynamically chosen to ensure simultaneous depletion of fuel and oxidizer. The second stage center engine early cutoff is done to reduce longitudinal (pogo) vibrations rather than to limit acceleration; this was instituted starting with the Apollo 10 flight.

The third stage doesn't use all its fuel in this portion of the mission; most of the fuel load is for the later lunar injection burn, and that's why its acceleration curve is so flat in comparison to the others.

Mercury-Atlas missions were more dramatic: 1.35g off the pad, peaking around 7g just before the booster engines shut down and dropped away, climbing again to almost 8g before the sustainer ran out of fuel.

Here's Mercury-Atlas 7: Acceleration time series plot from 1.4g at 0:00 to 2.1g at 0:55, then in a steepening curve up to 6.8g at booster cutoff at 2:10; rising again from 1.3g to 7.8g at sustainer cutoff at 5:10

Gemini-Titan peaked above 7g on the second stage. Here's a plot from the Gemini VIII mission report:

g force time series plot, increasing from about 1.25 g at liftoff in an inverse-linear curve to booster cutoff at around 155 seconds, 5.5 g, rising again from 1.35 g at second stage ignition to nearly 7.5g at second stage cutoff at around 335 seconds

Both Atlas and Titan were designed as ICBMs, so not really optimized for human comfort.

The Space Shuttle was much more gentle in comparison; at solid booster burnout it reached the first peak of 2.5g, briefly falling a bit below 1g then slowly picked back up to 3g on the main engines; the mains were repeatedly throttled down to hold about 3g for a little over a minute.

I think Soyuz does under 4g on launch.

Other things being equal, a higher-g launch can be more fuel efficient, because less energy is lost to gravity by getting to orbit more quickly, and gravity losses normally dominate over drag losses. Keeping STS down to 3g was a challenging design goal - it's hard to build deep throttling capability into an engine, but the shuttle was designed to carry (relatively fragile) scientists rather than ex-military fighter jocks. Soyuz is a bit of a compromise there.

Falcon 9 starts at about 1.15g, and depending on payload would have a first-stage peak acceleration of around 4.5g, but it appears to throttle its engines back toward the end of the first-stage burn to maintain closer to 3.5g.

Re-entry and landing G-Forces

I haven't found a good time series graph of reentry force, but the peaks are relatively brief -- force increases as the capsule descends into denser air, but decreases as the capsule slows, so the higher the decelerating g-force, the shorter it's going to last.

Mercury astronauts took about 11g peak force on re-entry, Apollo about 6.5-7g, space shuttle about 3g.

Again, Soyuz does about 4g here, I think.

There may be a pretty good jolt at touchdown/splashdown, too. Some of the Apollos hit rising waves at the end of the ride for very brief 15g bump.

STS and Soyuz g-forces are necessarily low, again, because they carry civilian crews. In the case of the shuttle, again, it's a major design consideration: the gentle re-entry means the ship has to deal with a prolonged period of high thermal load, which requires fancy and vulnerable ceramic tiles rather than a simple ablative heat shield.

shareimprove this answer
edited Dec 14 '18 at 17:42
answered Jan 17 '15 at 0:21

Russell Borogove
85.3k3287370
The center motor was not shut down to limit acceleration. It was shut down to limit Pogo-vibrations that could damage the ship. – Gunnar Øyro Aug 23 '17 at 19:51
The first stage center shutdown is for acceleration limiting according to the flight manual: "S-IC center engine cutoff occurs at 2 minutes 5.6 seconds after first motion, to limit the vehicle acceleration to a nominal 3.98 g." The second stage center shutdown is a pogo-control measure. history.nasa.gov/afj/ap08fj/pdf/sa503-flightmanual.pdf – Russell Borogove Aug 23 '17 at 21:34
"a higher-g launch can be more fuel efficient, because less energy is lost to drag and gravity by getting to orbit more quickly": Wouldn't higher-g launch mean MORE energy lost to drag? Higher acceleration means higher speed while low in the atmosphere and thus higher drag. Energy loss to drag is the same as its (negative) work, which is the integral of its force (or, rather, its projection on the velocity vector) over the path. The length of the path in the atmosphere doesn't depend on acceleration, but higher acceleration means higher force. – Litho Aug 24 '17 at 7:45
@Litho - whoops, good catch; I've corrected that. Note that gravity losses usually dominate over drag losses (by around 20:1 for Saturn V, for example), so the conclusion is the same. – Russell Borogove Aug 24 '17 at 16:10


To answer your second question on the astronauts' experience and how much thought went into adjusting the g-force profile of a launch, NASA published a document that contains information on the g-force survivability range of a human.

Here is the Paper, the relevant figure you want is Figure 5 which is about halfway down the page. The figure is a plot of g-forces in the y axis and time in the x axis with highlighted regions of survivability.

Fig. 5 - Human time-tolerance: acceleration

 

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Spaceships: Hulls and Bigelow Aerospace Is Building The World's First Space Hotel | Answers With Joe

Robert Bigelow became a billionaire as the owner of Budget Suites of America hotels. But now he wants to build hotels in space. And his company Bigelow Aerospace is getting closer with their inflatable habitats.

https://www.youtube.com/watch?v=5nE3UO1kqv0

Problem with using fabric based hulls is that volume counts more than mass.

 

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Starships: Engineering and the One Shot Jump Drive

Default at ten tonnes and fifteen megaschmuckers providing two hundred parsec tonnes.

Twenty percent decrease in tonnage gives four tonne overhead and four tonne core/capacitors at three and three quarters megaschmuckers.

Though if cost is calculated at de facto per tonne, three hundred and seventy five kay schmuckers, that's three megaschmuckers.

Minimum ten tonne jump drive, six tonne core/capacitors, that's a performance of three hundred parsec tonnes at a cost of three and a quarter megaschmuckers.

Make it a budget version with energy inefficiency, it costs 2'812'500.- Credite Imperiale and needs 39 energy points to transition three hundred parsec tonnes.

 

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Starships: Engineering, Deconstruction, and the One Shot Jump Drive

For the default ten tonne jump drive, overhead/capacitors are five tonnes, and core/capacitors are another five tonnes; while you really don't have to worry that much of deterioration of the capacitors with extensive use, at seventy five percent discount, I certainly wouldn't mix them with default capacitors, not that it is clear that accelerated deterioration is part of the one shot process.

As such, you initially remove the capacitors, and are left with four tonnes each of overhead and core at nine megabux, which results in 1'125'000 CrImps per tonne, at seventy five discount 281'250 CrImps per tonne, with a further budgetted variant at 210'937.50 CrImps.

Bare overhead weighs in at 3.2 tonnes, budgetted capacitors have a 62.5 energy point capacity per tonne at 562'500 CrImps.

Target four hundred parsec tonnes.

Required would be double of initial core at 6.4 tonnes, plus overhead at 3.2 tonnes, equals 9.6 tonnes at 2'700'00 CrImps, budgetted 2'025'000 CrImps.

Minimum one shot capacitors for 52 energy points is 0.832 tonnes, round that off to 0.9 tonnes at 455'625 CrImps, budgetted 341'718.75 CrImps.

End result ten and a half tonne one shot jump drive rated for four hundred parsec tonnes, at 2'366'718.75 CrImps.

 

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Spaceships: Engineering, Mechanics, and Why Machines That Bend Are Better

Compliant mechanisms have lots of advantages over traditional devices.

At the above link, you can download 3D-print files to make some of the objects in the video, plus learn more about compliant mechanisms.

What I learned about compliant mechanisms I summarize in the 8 P's of compliant mechanisms:

1. Part count (reduced by having flexible parts instead of springs, hinges)
2. Productions processes (many, new, different enabled by compliant designs)
3. Price (reduced by fewer parts and different production processes)
4. Precise Motion (no backlash, less wear, friction)
5. Performance (no outgassing, doesn't require lubricant)
6. Proportions (reduced through different production processes)
7. Portability (lightweight due to simpler, reduced part count designs)
8. Predictability (devices are reliable over a long period of time)

https://www.youtube.com/watch?v=97t7Xj_iBv0

And possibly, missile arming safety switch.