Cunjo Carl

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About Cunjo Carl

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    Rocket Fancier

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  1. Perhaps the sun is just sideways? .... /s I'm taking notice of all the space clouds in the back, and thinking this may be in a nebulea? The nearby space clouds are lit only from the top, whereas the distant background clouds are lit diffusely from the back. If it's a stellar nursery, perhaps there's an interesting nearby feature temporarily lighting the otherwise nighttime side of Duna? Sounds good anyways! Gonna wreak havoc on the orbits though....
  2. Someone made a special Gold-Palladium alloy which is apparently so good at cracking hydrocarbons, that the surface builds up a layer of graphite 'coke' at room temperature. This tiny layer is so durable that the alloy becomes effectively one of the most abrasion resistant materials in the world. That's crazy because Gold Palladium itself is pretty dang soft.
  3. Getting one of these into space would be an undertaking of Kerbal proportions!
  4. Not sure if he counts as fringe, but here's a nice five year design along the lines of your statement. Hugely worth the watch in my opinion, he does a great job explaining the present day of fusion. For present day 'hyperfission' on the other hand there's this reported 1H + 1H -> 3 Kauons + 300MeV reaction. Kinda crazy! Not sure I believe this guy's theory, but his experiment's an interesting one. . It is definitely an easier goal than fusion! Whether it's real...? Probably not, but bizarrely not "definitely not". Still looking into it.
  5. My honest answer would be to go for both! Maybe build in an interesting tradeoff between the two, so the crew needs to make difficult decisions when confronted with a new challenge or one of the drives going offline. Safe travels, come back and say hi some time if the mood strikes!
  6. Glory days of the RPN calculator right there! Also I totally get what you mean. If you know what assumptions to make it can feel rather cheeky what you're able to get away with!
  7. I took a quick peek at the web page for the program you found, and it looks like it does everything my spreadsheet would and then some! My plan of attack was: 1. Find an engine with known: Propellants, mix ratio, expansion ratio, Isp (ASL), chamber pressure, and exhaust exit pressure (guesstimate this last one by looking at exhaust expansion as it exits the nozzle) 2. Use the Isp (ASL) to back-calculate the temperature in the combustion chamber. Just use guess and check iteration until the right temp is found- the adiabatic flame temp can be used as a starting guess. I was planning on using JANAF thermodynamics values and an assumption of fast kinetics and adiabatic expansion (so all points are at equilibrium, and all of the losses are modeled as a simple reduction in combustion chamber temp). The one thing I wasn't sure about is how to deal with the non-ideality of the gas. I was planning to use Redlich-Kwong, but there's quite a few exhaust components I'm not confident I could find critical temps/pressures for. For starters, the ideal gas assumption may be 'close enough' though. 3. Using this combustion chamber temperature, calculate the Isp of the engine for different expansion ratios. Of course real life doesn't really work like this, but the problems caused by the assumptions made here will tend to cancel eachother out. It should come out pretty close! Since you've got the program, maybe give this a go?
  8. No, the equation is just for the Ve term (v3 is the exhaust velocity). The Pe-Pa is something you'll need to calculate within your model/sim. I went ahead and typed in the subscripts so it's a bit easier to read: Cheers!
  9. My grandfather worked in the Mariner program, so he made sure to snatch up some 10yr Apollo Program anniversary stamps when they came out! They started at 8 cents, and became family heirlooms.
  10. Hey, @Exoscientist. I ran the numbers for the simplest assumptions and got this for exhaust velocities with upgraded nozzles: Where: v3 is the exhaust velocity for our engine with the bigger nozzle v2 is the exhaust velocity for our engine as it is now (the 1atm version) P3 is the exhaust exit pressure for our engine with the bigger nozzle P2 is the exhaust exit pressure for our engine as it is now (~1atm) P1 is the chamber pressure R is the universal gas constant (8.314 J/molK) Cp is the exhaust gas' effective heat capacity (averaged on a molar basis between the constituents, and using specifically the molar version, denoted with a big Cp rather than a little cp) This assumes constant Cp, which is a really terrible assumption. It also assumes frozen equilibrium and all sorts of things! These assumptions will by-and-large decrease the calculated value of v3 relative to what it would actually be. Still, this is the first order equation. If it's enough let me know! Otherwise I'll probably keep chugging until I make a better version. The next step up would need a spreadsheet to work. What's the thoughts? You can get Cp values from JANAF, but I'm sure there's easier sources out there.
  11. And to add to that even further its exhaust products were mostly water, which has a much better expansion efficiency (gamma) for a given pressure+nozzle than any currently fired alternatives. I think the space shuttle main engines were really amazing at what they were able to accomplish! Not all amazing things are practical though, of course.
  12. I'd need to rely on some pretty old brain cells, but this is up my ally. The difficulty of a problem like this really hinges on the assumptions we're willing to make. Ideal gas? Frozen Equilibrium? Isentropic Expansion? Constant Cp? There's a lot to it, so I think I'd need a bit of a better idea of what kind of end product you're going for. Would it be a simple equation that could get you in the ballpark, or a little program to get you a bit closer? Please let us know more specifically what you're interested in and I'll poke at it a bit to see what would be involved and whether I can give it a go. For the Isp calculations that is- the payload calculation would be a whole additional can of worms!
  13. I'll just nudge this in here then... It's a race for stock KSP designed to take 1-2 hours on the first try, and the format+difficulty are purposefully designed to make for entertaining viewing on a stream. If it matches what you're going for feel free to go for it or use the idea as a template. Something else that's proven really popular lately in gaming streams for older 1 player games like KSP is 'randomizer races' (you can type the term into youtube) where elements of the game are jumbled up and the players need to race to figure out what's going on and accomplish some goal (normally beating the game). I could imagine you could make a quite entertaining race by jumbling up the tech tree and doing a 200% science career run to the surface of Eve or Tylo and back. Or maybe a sandbox race limited to really wacky parts? I'm mostly just putting thoughts on paper here there's plenty of fun ways to do short competitions in KSP. It might be worth just gathering some friends together on skype and trying some things out just to see what's fun to run and makes you want to run the competition again! Like others are saying, that's probably the most important part. Just my 2 cents. Good luck!
  14. Definitely give the assist a shot before you tap out. If you've never had an opportunity to try one before no time like the present, am I right? . The way to do it: When your craft is about a couple weeks away from Kerbin's SOI, you can maneuver the Periapsis to be ~150km-200km away from Kerbin (I believe on the night side). You'll notice when you do this, the craft will still fly through Kerbin's SOI, but when it emerges your Apoapsis with respect to the sun will be lower than Jool's orbit. The lower you can get that Apoapsis the better! If you put a maneuver node out at the Ap you can click the button that lets you see Kerbin close encounters on future orbits. Simply try different Periapsis altitudes until you find one that gives you a nice close encounter with Kerbin again somewhere a couple years down the line. When you finally return, you'll have much less speed than before, so if the reentry is a close thing now it should become easy. When done properly, this should only takes 20-50m/s of deltaV. Good luck!