Kerbol Macrosystems

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  1. That's exactly what I was thinking.
  2. My own explosive testing program occasionally reaches space too. This would be more for the artful size of explosion. Either collapsing the stack in such a way that there's beauty when the boosters fly off, or something modded to have exquisite detail.
  3. @Snark The title of your video ("KSP Blender Fuel-Tank Example Demo") makes me wish there was a KSP version of "Will it blend?" I would definitely watch somebody blow up various interesting ship configurations. Though, I guess this is basically any Danny2426 video with a kraken drive.
  4. Or Randall Monroe (it's in footnote 3).
  5. Rabbids are something that shows up in the Rayman series. They have their own line of party games. https://en.wikipedia.org/wiki/Rayman_Raving_Rabbids
  6. Friction is not analogous to compression heating. These are two very different physical phenomena and are not just statistics. Let's start with friction. Friction is a form of energy transfer. It involves at a minimum 1 solid surface. Friction comes from the shear force (kind of like pressure, but parallel instead of normal to a surface) that comes up whenever two things slide across each other. There are shear forces in flowing fluids, but this leads to the concept of viscosity. When you have 2 solid surfaces your coefficient of friction can be quite high. We can turn the friction force into an energy by multiplying that force by a distance (E=F*d). You'll find the mechanical energy that went into overcoming friction comes out of the process as heat. We typically call friction between 1 surface and a fluid drag. You'll find that drag causes very little heat in air, because there's just not that much energy required to get air out of your way. Especially in the upper atmosphere. You can prove this one to yourself too. Run a re-entry with a known vessel mass (e.g. the starting capsule at 0.84 tonnes). Watch for the fire to start. Next note the acceleration on your vessel by timing how long it takes you to drop 1 m/s velocity. Divide the mass of the vessel by the time to drop 1 m/s to get your force. (a=v/t, we set v to 1 m/s and we measured t) then F=m*a Adiabatic temperature change requires no energy transfer. That's the definition of adiabatic; no energy or mass transfer. Under moderate conditions this is governed by the ideal gas law, P*V=n*R*T. One thing that is not immediately obvious is that this equation has units of energy. P is pressure, is force / length2. V is volume, which has units of length3. When you multiply these together you get force * distance, which is energy. When we said we do things adiabatically our change in energy is 0 and our change in mass/matter (n) is 0 as well. In order to satisfy these conditions P*V/(n*R*T) must remain constant. Thus if we keep our volume the same, and drive up the pressure we will have a large increase in temperature as well, possibly to the point of generating a plasma. Now why is the air in front of a re-entering capsule getting heated adiabatically? Isn't it flowing around the capsule? This one is more of a timing kind of issue. We have to remember that orbital velocity is ridiculously fast. So fast, that air molecules can't get out of the way and get compressed. They're compressed so fast so there's no time for heat transfer to dissipate the energy created by the capsule ramming into the air. So we have the kinetic energy of the vessel being transferred to the air in front of it. The energy went up, so P*V went up, and n*R*T went up. Air is compressible, so we know P went up and V went down, but P*V went up. On the n*R*T side we know that R is a measured constant. It's not changing. Remember we're moving really fast, so there isn't really time for heat and mass transfer in the ram area. Also we have a detached shock cone, which will have a stagnation volume right in front of the vessel. So if n isn't going up and R isn't changing, that means T is going up if n*R*T is going up. Real gasses do depart from the ideal gas law above, but these departures are well studied as an equation of state, or other thermodynamic models. You can think of the equation being modified to P*V=Z*n*R*T, where Z is a correction function. The correction function has been studied for over a century, and many models are available depending on the conditions you are studying
  7. If you're a new player this would be the Coalition Orbital Destruction and Explosion project.
  8. I've worked with gaseous fluorine, but never liquid fluorine. I can only imagine this ending with everything on fire.
  9. This seems like the time to mention that you can search moar in KSPedia, though they don't seem to mention that Moar is the god of reaching orbit.
  10. I'd love to see the physics engine redone. The things I'd want to see are: Planetary axial tilt and complex orbit approximation. Things like sun-synchronous orbits, fuzzy orbits/ballistic capture, and Lagrange points. These things wouldn't be that bad when you're focused on a ship, but would currently limit you into physics warp in order to be able to handle appropriately. I'm thinking that when you're focused on a ship you get N-body physics from the body you're orbiting, its moons, and Kerbol. When you're orbiting Kerbol it's just the main planets, no moons. Time warping requires some shortcuts. A normal time-warp puts you back into Newtonian physics. You could shortcut a Lissajous orbits (around L4 and L5) by treating L4 and L5 as if they had a pseudo-SOI. If your orbit closes within the pseudo-SOI the game will treat you like you're orbiting L4 or L5 with some altered but predictable shapes. This only happens if you already have a closed orbit around those lagrange points when you begin time-warp. Same thing for sun-synchronous orbits. If you get an orbit close to the parameters reported on wikipedia the game realizes that you have the correct precession and keeps the angle between your orbit and the sun fixed. I'm not sure there's an easy way to shortcut ballistic capture, as these become very complex orbits. The only thing I could think of is to have a "propagate orbit" button. When you click this the game will pause and devote all of its resources to do a detailed projection of your orbit into the future. Your vessel then becomes locked onto this path for however long you propagated it for. The duration for propagation would be user-settable. Getting an appropriate capture would require some intuition of how long the maneuver would take in game-time. Once you reach the end of that propagation time-warp goes back to Newtonian physics. During the propagated orbit most of your options for using the vessel are locked out. You can't fire engines, rotate the craft, or activate a separation. Science experiments could still be run as these do not alter the position of mass within the ship. EVA would be difficult because you would need a kerbal with active physics to interact with a ship that has locked physics.
  11. I was thinking of these as in-game mods. I guess the near-future tech already offers some parts with huge ISP, but Project Pluto is a little unique. It's a fuel-less engine that generates a ton of heat, so it can never slow down without overheating. Plus if you don't play with deadly re-entry then shielding is not a problem
  12. https://en.wikipedia.org/wiki/Project_Pluto Project Pluto - if a nuclear reactor and a ram jet had a baby. Take all the water out of a nuclear reactor and change the geometry of the fuel cells. Air goes in the ram scoops, passes over the nuclear fuel rods to heat up, and creates thrust out the back. If developed to fruition would be able to fly for months at a time. https://en.wikipedia.org/wiki/Fission-fragment_rocket Like a NERVA, but without the hydrogen. You let the core heat up until it begins to vaporize and become a plasma. Plasma is ejected from the rocket like an ion engine. Depending on the geometry the ISP can get on the order of 100,000 s or 1,000,000 s.
  13. A launch optimizer would be a good project. You would need to run a minimization algorithm that alters thrust and attitude throughout a flight, using a given drag profile and atmosphere characteristic. If that seems to easy, do it again for a space plane by adding lift characteristic and angle of attack. If this is too hard, you could write a de-orbit targeting algorithm that can help a vessel target its re-entry landing location.