quote:
Constructie:
And this will be true for any steel cylinder that is 13km long and consistent.
So the width of the cylinder will only matter when it comes to the weight of the interior and amount of exterior forces. so really, it only needs to be maybe one or a few meters thick.
It should be able to take a force equal to accelerating it at 146m/s2, as long as it's spread out evenly along the spacecrafts length.
There are probably other effects of physics that may interfere, such as the finite speed of forces. But I don't think the craft is going to accelerate at any higher rate than 10m/s2, for the comfort of the travellers. That's 1/14 of the force it can theoretically withstand when empty. And there are even stronger materials out there.
It's going to be hard to build, of course. But in space we have access to vacuum welding, where the welded surfaces are extremely homogenous with the material itself and it could be a good technique to use.
One issue is, that thickness of skin only adds to the mass issues and inertial issues.
That's what my calcualtions were trying to find out, how the thickness of the cylinder would change it's strength and mass. And it seems that the strength and mass scales at the same rate, which means that the width does not have an impact on the cylinders ability to support itself (but it will obviously have to be thick due to the weight of the interior and to be able to take exterior forces).
Voortstuwing:
It utilizes nuclear pulse propulsion by way of fusion bombs which when ejected emit a conically shaped thermonuclear detonation that impacts against a massive nanocarbon-coated (or just refined graphite) ablation plate of tungsten and titanium which absorbs the kinetic energy of the aforementioned blast through a system of shocks in order to afford the ship forward thrust... which theoretically overtime should allow for acceleration towards an upper maximum velocity of 0.25C; or 46,500 miles per second. Potentially greater if anti-matter catalyzed bomblets were developed in tandem with significant modifications being made to the ship's structure, fuselage and various component systems in order to endure such power output and stresses during relativistic travel approaching or exceeding 0.50C.
Anti-matter catalyzed bomblets have practically the same explosive properties as a thermonuclear explosion, except that the device which would be ejected from the rear of the ablation plate could be many many times smaller, which equates to greatly extended pulse magazine capacity.
The nuclear pulse propulsion concept doesn't necessarily rely on the concussive wave of an exploding nuclear device, but rather the shaped directed charge of particles resultant from that explosion which will be hitting the ablation plate at several hundred thousand miles per hour upon detonation.
Cumulatively, this translates to a massive transferal of kinetic energy from the pushed ablation plate into the shocks which are subsequently compressed as the craft is moved forward.
Acceleration or deceleration doesn't take place over "one second", or even across hundreds of thousands of miles.
It would most likely take months of not up to a year to reach .25C with the yield of bombs I have in mind.
Probleem: Teering snel dus, hoe rem je af en stop je netjes bij halte Alpha Cantauri?