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OhioBob

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  1. OhioBob
    Kopernicus is version locked so that each version of Kopernicus will work with only one version of KSP. The version numbers must match. Let's say, for example, you are playing KSP 1.8.1. Then you must use a version of Kopernicus that is numbered 1.8.1-x.
  2. OhioBob
    It's easy to check if it's working or not. Just use the cheat menu to land a probe on Toutatis at latitude 0, longitude 0. If it's working you should read a temperature of about 443-445 K, and if not about 390-400 K. Sigma88 made HeatShifter at my request when I created Toutatis. At one time he had it working in 1.7.3 but that required a separate version of the plugin. The released version probably only works in 1.8+, but haven't verified that. I assume the reason it doesn't work across versions is due to the Unity change in KSP 1.8, but I'm not certain of that.
  3. OhioBob
    That's not a viable option because it will cause other problems. For instance, the stock delta-v readout computes SRB burn time on the basis of maxThrust as specified in the configs. The thrust curves are written so that the mean value of the curve is 1, which effectively means that maxThrust = average thrust. Therefore the delta-v readout correctly computes burn time. If the curves were written so that the maximum value were 1, then the mean would be <1, resulting in the delta-v readout underestimating the burn time. This could have bad consequences. For instance, it could mess up staging sequence if the SRBs burn longer than expected. So it sounds like having something messed here up may be unavoidable. No offense, but if I'm going to make it work correctly with something, I'd rather it be the stock delta-v readout.
  4. OhioBob
    I wish I had seen this earlier. This article says that a minimum oxygen concentration to burn hydrogen is 5%, and to burn methane is 12%. Using those numbers I compute:
  5. OhioBob
    @Gordon Fecyk, it sounds like you don't need it, but I was already in the process of doing this, so I might as well post it. This is the hydrogen engine with the oxygen content bumped way up. I set the LOX/H2 ratio to 4, which is 1/2 the stoichiometric ratio.
  6. OhioBob
    I just discovered that I use GOX in my last couple calculations instead of LOX. I've fixed it.
  7. OhioBob
    The case of the hydrogen engine is different than the methane engine in that there is a great abundance of fuel. The injected oxygen is not going to have any problem finding plenty of hydrogen to react with. But if the oxygen concentration is too low, is it possible that the engine could actually blow itself out and not sustain combustion. I don't know the answer to that. With the numbers I used, the oxygen concentration in the combustor is only 4% by volume.
  8. OhioBob
    I just went the other extreme and added twice as much oxygen as needed to fully oxidize the methane. Hopefully that's enough to assure complete combustion. The results are far different.
  9. OhioBob
    @Gordon Fecyk, while I can do the math, I'm far from an expert on combustion in jet engines. What the math tells me is the more fuel rich we run the engine, the greater the Lox-only Isp (but the lower the overall Isp). I took the LOX concentration down to the point where the combustion temperature was about 1000 K (I was afraid to go any lower than that). What concerns me is if that's really enough oxygen to support combustion, particularly in the second case. With the air-oxidizer ratio that I used, the mixture of gases in the combustor ends up being, 86.6% N2, 5.5% CH4 and 7.9% O2, by volume (mole). That's a very low oxygen concentration. I did the math like all that oxygen is burning with the methane, but would that happen in real life? Could that small amount of oxygen find and react with all the methane before being discharged from the engine? If in practice the combustion is incomplete, then my numbers are wrong. Maybe more oxygen has to be added to assure adequate combustion. And if that's the case, then the Lox-only Isp would plummet.
  10. OhioBob
    At the upper edge of its atmosphere, 5783 m/s.
  11. OhioBob
    For comparison, here are some calculations for a nitrogen-methane atmosphere:
  12. OhioBob
    @Gordon Fecyk, I've done some calculations, but I went about it very differently than you. I just made some basic assumptions about the environment and engines, from which I computed the specific impulse. Maybe this will help.
  13. OhioBob
    The thrust curves in BetterSRBs are specifically designed so that they average exactly 100%. So roughly half the time they exceed 100%, and the other half they are below 100%. By making the mean value equal 100%, maxThurst as specified in the engine configs equals the average thrust. This allows the in game delta-v readout to correctly compute the burn time.
  14. OhioBob
    I just noticed in the OP that you're using KSP 1.7.3. HeatShifter will likely not work in that case. I believe it only works in 1.8+. Without HeatShifter, the hottest and coldest spots on the planet are shifted 45 degrees, so the hottest time of day is mid-afternoon. That works for a rapidly rotating body but not a tidally locked one. HeatShifter takes out the offset so the hottest spot is the subsolar point, and the coldest spot is the antisolar point. Between those two points is a smooth gradient, which isn't entirely realistic, but it's the best I can do within the confines KSP. At "sea level" (the datum), the temperature at the antisolar point should be about 100 K, and at the subsolar point about 460 K. All around the day-night terminator will be about 280 K. Though because of altitude and other factors, you'll likely read different temperatures. (edit) On second thought, no it isn't a smooth (straight line) gradient. I think the formula is, temperature = minTemp + deltaTemp * (0.5 * cos(zenithAngle) + 0.5) Where minTemp is that at the antisolar point, deltaTemp is the difference between the subsolar and antisolar points, and zenithAngle is the angle between the zenith and the sun.
  15. OhioBob
    Before going to Toutatis, you might want to consider installing HeatShifter. It's just a small plugin that fixes an issue in the way that stock atmospheres work, preventing proper temperature distribution on tidally locked planets. It's needed to experience Toutatis the way it was designed. I plan to bundle HeatShifter with the next release of GEP, but for now you have to install it separately.
  16. OhioBob
    I don't know much about jet engines, but I do know rocket engines. I presume it's basically the same. I'll do some math to see what I can come up with.
  17. OhioBob
    UPDATE Version 2.0.6 Changelog Added a whitelist to keep Restock from blocking parts. Added "eve" to tags list. See opening post for download link and instructions. This is planned to be the final release of the old version of Eve Optimized Engines. v2.0.6 is required for those still playing pre-1.9 versions of KSP. Going forward only the 3.0 version of Eve Optimized Engines will be supported and updated.
  18. OhioBob
    It's Restock screwing everything up again.
  19. OhioBob
    I don't know. I use very few part mods, so it never gets tested with a lot of part mods installed. What version of Eve Optimized Engines are you using? If you're on KSP 1.8.1, you have to use v2.0.5. V3.0.1 only works with KSP v1.9+.
  20. OhioBob
    You should be able to move your save from 1.9.0 to 1.9.1. Just drag the folder from one installation to the other.
  21. OhioBob
    That doesn't completely surprise me. If you have a big enough drogue, or enough drogues, it should still be possible to land on parachutes only. We just tried to make it very impractical to do so for a vessel of any significant size.
  22. OhioBob
    No, Kopernicus is version locked. For instance, Kopernicus 1.8.1-1 will work only with KSP 1.8.1 and no other. Since we're already up to KSP 1.9.1, it's possible Kopernicus could skip 1.9.0 entirely. It's happened before.
  23. OhioBob
    UPDATE Version 3.0.1 Changelog Fix compatibility issues with mods that change the engine module. Added engine specifications to the variant descriptions. Added "eve" to tags list. See opening post for download link and instructions.
  24. OhioBob
    UPDATE Version 3.0.0 Changelog Mod has been completely rewritten to provide part variants in lieu of new parts.. See opening post for download link and instructions. v3.0.0 is a complete makeover in the way that Eve Optimized Engines works. It now requires B9 Part Switch as dependency, and it works only in KSP 1.9+ (continue using v2.0.5 for older versions of KSP). Gone are the old engines, such as the Viper and Cobra. (The old engines still exist, so vessels built prior to v3.0.0 will still work, but the parts are now hidden and can no longer be used in new construction.) Eve optimized engines are now variants of the standard stock engines, selectable by right-clicking on the part in the editor. The variants are unlocked as part upgrades in the tech tree.
  25. OhioBob
    UPDATE Version 2.0.5 Changelog Fixed a problem with internal naming of parts. See opening post for download link and instructions.
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