VaporTrail

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About VaporTrail

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  1. Hmm... probably not, thought I had all my mods on CKAN. Don't see Tweakscale on there though. I'll try a manual update. Ding... looks like that was it... move along.
  2. Question: Is Tweakscale supposed to change the electrical power generation potential of rescaled solar panels, specifically Gigantors? I've got a test craft with four different scale Gigantors and they all report the same energy flow.
  3. Graphite Radiator Folding Medium, x4, 100% scaling. Believe it's out of Interstellar.
  4. Ok... still attempting the solar sat. Have a basic design that's working... ish. But something's not gelling... or several things. Only thing different between the two is altitude above Kerbol. Sixty Gigantors @ 100% scaling. Radial out, transmitter on out facing end. Panels flat on to Kerbol, radiators edge on behind support arms). ElectricCharge capacity x 50 is Max microwave transmission, right? I'm getting a quarter GW transmitted, which seems right given energy flow on panels but... it goes down closer in? Sat is still at 800,000,000 m... but pushing only 205 MW and falling (~4 minutes game time from second pic). What am I missing? Thermal effects on my panels, but no waste heat in my radiators... I get much closer and the panels burn off (without a single tick of waste heat in the radiators). I know we're in the middle of a patch cycle, but I was having similar issues before the patch went live. Is something screwy actually going on, or is it in my head?
  5. Nope. Worst case, you'd have the plutonium rod go critical in your hand from the neutron flux of the core (and you're dead anyway). Best you could hope for is a fizzle yield that breaches containment... but that doesn't specifically require plutonium. I actually had a method worked out to break the reactor when I worked on one, which took a wrench, a screwdriver, a (specific) key, four to six uninterrupted hours, and a large rubber band (Swiss-Army Knife optional. This was fifteen years and two lifetimes ago... the equipment has changed since to prevent that method from working). It worked because I knew the safety measures built into the system, and actually used them to accomplish the goal. Granted, I'd never actually have tried it... but it was an interesting intellectual exercise. Hardest part was getting a hold of that key. Definition of "a small amount" of uranium can still result in a fuel mass of tons and a huge volume. A PWR fuel assembly isn't just the fissile materials, it's the support structure, cladding, non-fissile uranium, control rods and mechanisms, and everything that makes the fuel assembly work. Even a pebble-bed design doesn't use straight uranium... the pebbles are mostly graphite wrapped around uranium dioxide, and not very dense at all compared to an equal volume of metallic uranium. You can't refuel a reactor like you would a car (well, maybe a PBR, but not a PWR). Pulling a PWR reactor core is a lot like an engine teardown/rebuild on an automobile... if you happen to be an automotively inclined weasel who's violently allergic to motor oil. The fuel rod assemblies have to come out as a piece, and go in as a piece, and coming out they're radioactive as all get-out coming out, and not really pleasant going in either. Each fuel assembly has to come packaged in a transportation unit, that employs shielding (so the fuel in the new one doesn't deplete, and the old one doesn't cause a mess). Refueling a CV(N) (two reactors) is an extended process that takes dozens of people months (at best) to accomplish. Granted, it takes on the order of two decades of run time to deplete the cores... so the trade-off is worth it.
  6. Not to mention that Deuterium/Tritium fusion has an theoretical energy density ten times that of fission on a strictly fuel related level.
  7. Actually, you can "just put a bunch of uranium together and get a reaction going," and it's actually a major part of nuclear weapon design, as opposed to reactor design (not that an understanding of it isn't necessary here). The term is "critical mass". It really depends on your density of U-235 (or other fissile material). Get enough U-235 (or U-233, Pu-238, Pu-239, yadda, yadda...) close enough together and you will have a self sustaining nuclear fission chain reaction. Early (failed) designs for nuclear weapons used moderators, but almost all modern designs use nearly pure metallic uranium, plutonium, or some other fissile fuel. Depending on the type of weapon, the sub-critical mass of fissile material is turned into a super-critical mass (through rapid joining of two sub-critical masses, usually used in uranium bombs, or imploding a sub-critical mass into a high-density super-critical mass, used in plutonium bombs), allowing a (short-lived) sustained chain reaction. In short, bomb go boom. A mass of lower grade uranium (approx 15% u-235, 85% u-238 or other non-fissile materials) has a bare-sphere critical mass well over 600 kg, while a bare sphere of weapons grade uranium (near 100% U-235) is critical at about 52 kg, or a diameter of 17cm. A neutron moderator allows a sub-critical mass the ability to go super-critical because it slows down those pesky fast neutrons to thermal neutrons, which are much more likely to be captured by the fissile material, and thus allow a sustained chain reaction. In a pressurized water reactor, water is used as a coolant, heat transport medium, and a neutron moderator, all at the same time. The thing about this critical mass is not that it goes boom. It just gets hot. Really, REALLY hot if the reaction goes on long enough. Hence the term "meltdown," which is basically when the reactor gets all gooey and delicious. A big worry in the early days was "China syndrome," where the molten reactor was supposedly able to tunnel to "China" (or at least to the water table) and become a big radiological hazard through a huge radioactive plume. Chernobyl was almost an example of this, because of the design of the reactor plant. The core was situated above a pump reservoir, that would have (had not three divers sacrificed their lives to manually operate valves to drain it) caused a steam explosion that would have worsened the already bad situation several-fold. Just one more thing. Every time someone uses the line "It's going critical!" in a film containing a nuclear reactor, a nuclear engineer laughs himself to (near)death. Just going critical isn't a problem. In fact, reactors go critical (and super-critical) all the time, as a part of normal operation. The degree, and control with which, a core goes super-critical is what matters. A (properly controlled) nuclear reactor generally goes super-critical relying on the one percent of neutrons that are released well after a fission event. These "delayed neutrons" (along with neutron-poisons in control rods, etc) are what allow the nuclear reaction to be controlled on a human time-scale. An uncontrolled power excursion in which the reaction is being sustained on the neutrons born directly from fission (produced in less than one shake, and yes, that IS a unit of time... from a fission event) is termed as a "prompt-criticality." The line between criticality and prompt-criticality is the dividing point between "reactor" and "bomb." Please note, that it is pretty much impossible to turn a (properly designed) nuclear reactor into what most people would term a nuclear bomb without actually disassembling said reactor and reprocessing the materials. However, you can cause all kinds of unpleasantness by exploding a nuclear reactor pressure vessel. Just not "earth shattering kaboom" levels of unpleasantness.
  8. Currently testing a solar sat. Trying to follow the wiki for solar sats. Having heating issues getting below ~750,000,000 km SMA (hyperedit for testing purposes). 200% Tweakscaled Gigantors, otherwise stock, overheat (despite two large graphite deployable radiators in shadow, behind the panels). Waste Heat for the entire sat stays at or near zero, as expected, but below 750 Mm SMA the gigantors tend to just overheat and explode. Best performance out of the sat was in the 60-70 MW range, as measured by beamed power from the microwave transmitter, which was in line with the rule of thumb prediction from the thermal helper (~0.36 AU, ~35MW heat production). From testing, it appears that tweaking the scale of the Gigantors has no effect on the heat experienced (100% scale panels seem to overheat just as much as 200%, no more, no less) or power generated (I had a 100% scale panel producing 9MW power while a 200% scale on the same arm with same 100% exposure produced 4MW). This isn't my first attempt at doing this... ... but my last attempt (pictured above) was so long ago that quite a bit has changed with stock KSP, much less KSPI(Ex)... and I'm wondering if a solar powersat is still a viable concept without resorting to additional mods for more robust solar panels. If it is, could someone point me in the direction of where they think I may be going wrong, please?
  9. Getting back into KSP and KSPI, and seem to be having an issue with MechJeb and Plasma Thrusters. I have a 12GW microwave reactor farm feeding a six relay array in Kerbin orbit, and I have a test article using the sphere receiver, an inline radiator, two medium graphite deployable radiators, a couple of gigantor solar panels and a plasma thruster (using mono-prop for boost to orbit). The test article makes it to orbital altitude under MechJeb but when it comes time to circularize, MechJeb just sits there and lets the node pass. I can make orbit manually, but when I try to use MechJeb to circularize (maneuver planner) for closer to perfect orbit... same thing, MechJeb just sits there. The nav-ball has a (I guess) accurate burn time and time to node displayed but there's no response from MechJeb. I haven't had an issue with conventional engines under MechJeb control. Is this a known issue, or am I doing or expecting something incorrectly?
  10. Now that is a truly mad invention... Pulse-Detonation Pipe organ. Start off with a suite from Phantom of the Opera, segue into Ride of the Valkyries... where do you go from there?
  11. From what I remember, Pulse det engines are essentially updated pulse-jet engines... which are WWII vintage in the real world. Maybe see the German V1, or "Buzz Bomb" for possible frequency starting places. Upon further research, the first (known) PD powered aircraft used four tubes firing at a freqency of 80 hz (I think this means each tube firing at 20 hz) https://en.wikipedia.org/wiki/Pulse_detonation_engine#First_PDE_powered_flight For comparison, the following is an 80 Hz test tone... I suggest playing at lower volume than usual videos, just in case.
  12. Ran into something that might need to be fixed. The 5-way RCS apparently has... orientation issues. Instead of being oriented outboard, the thrust from the top pair of RCS thrusters is oriented inboard.
  13. Just ran into this myself, (even though I run a modded install) [Orbit Targeter]: Target is null (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) Active Vessel is in atmosphere. Cannot save. (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) Active Vessel is in atmosphere. Cannot save. (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) tlsf_create: Pool size must be between 3208 and 1073745020 bytes. Crash!!! Have yet to try with temp gagues off, but in my case, (and others that I've read) it appears it's not the temp going up that causes the leak, but rather it appears (to me, at least) to be the parts cooling off (or the game code attempting it) while in atmosphere that triggers it. The same spaceplane that is suffering the issue made it to orbit with engines heated to the same level or more as the wings on the way down, and the engines completely cooled in orbit. The wings heat up on reentry, and then when I get about 10km altitude (10.5km to be more exact, around which the atmosphere changes in some significant way) I suddenly get CTD'd. Am about to attempt the F-10 workaround. F-10 workaround seems good. Successful landing on second attempt (found out I was also running very close to max RAM consumption... as I had a RAM-crash on my first attempt). Did some part pruning and managed a successful landing on second attempt. Jeb is back at KSP, and all is right with the wor... JEB. Get off of that booster, that's meant for a thirty ton payload. No, not in a minute... Aw heck, here we go again...
  14. Looks like I've got the same thing. Spaceplane in atmosphere, attempting to land at KSP runway after reentry. Wings and tail fins heated to ~50% and not noticeably cooling. [Orbit Targeter]: Target is null (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) Active Vessel is in atmosphere. Cannot save. (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) Active Vessel is in atmosphere. Cannot save. (Filename: C:/buildslave/unity/build/artifacts/StandalonePlayerGenerated/UnityEngineDebug.cpp Line: 56) tlsf_create: Pool size must be between 3208 and 1073745020 bytes. Crash!!!
  15. Made a Mk2 SSTO VTOL passenger (4) shuttle. Two Rapiers, two Leeches, two Ducted fans for VTOL. VTOL to Air-breathing Rapier transition @ 10 m. Rapiers + Leech scramjets @ ~10km. Leeches only @ ~20km... and it can make a 100km apoapsis without a closed cycle rocket assist from the Rapiers. That leaves the Rapiers for orbital maneuvering... Thrust limited to 25 m/sec^2 and a +20 pitch by Mechjeb, it pretty much flies itself...