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Absurdist

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Everything posted by Absurdist

  1. Radiators breaking doesn't seem to be related to sun tracking. --- Relevant line is this: if (radiatorIsEnabled && dynamic_pressure > [COLOR=#daa520]1.4854428818159388107574636072046e-3[/COLOR] && isDeployable) { The constant seems to be a magic number Fractal cooked up. Unit is atm, it's 150.5125 in pascals. On the huge heat radiator with 800m^2 on one side, that's applying a maximum of 120410 N of shear force. I'll check later how much von Mises stress that applies on a hollow tube to see if Fractal used a reasonable number. EDIT #2 (I used steel instead of Mo in my previous edit): Ok, here it is. I used COMSOL 5.0. Outside diameter: 1.1 m Internal channel is a 0.5 m x 0.5 m square. Length: 80 m Material: Molybdenum Reference: http://trace.tennessee.edu/utk_gradthes/1633/ Highest stress is 42.64 MPa near the base. Molybdenum maximum shear stress is ~500 MPa. This one is at 970 K, highest is 1.99 GPa. If anyone can provide more accurate geometry, I'll do another finite element analysis. Realism aside, Fractal set it too low IMO, unfurled radiators break at what.. 5 m/s on the runway? --- While I'm at it, here is another number that appeared on the code without explanation: [COLOR=#0000ff]float[/COLOR] dynamic_pressure = ([COLOR=#0000ff]float[/COLOR]) ([COLOR=#daa520]0.5[/COLOR]*pressure*[COLOR=#daa520]1.2041[/COLOR]*vessel.srf_velocity.sqrMagnitude/[COLOR=#daa520]101325.0[/COLOR]); 1.2041 is the density of air in kg/m^3 at 20 °C and 101.325 kPa. It's supposed to vary with location (air in Eve is not the same as in Kerbin) and elevation. --- Now, I'm not sure what this one does: [B]protected static[/B] [COLOR=#0000ff]double[/COLOR] alpha = [COLOR=#daa520]0.001998001998001998001998001998[/COLOR]; ... current_rad_temp = instantaneous_rad_temp * alpha + ([COLOR=#daa520]1.0[/COLOR] - alpha) * instantaneous_rad_temp; If you simplify the expression algebraically, the whole thing is just instantaneous_rad_temp. Though even with floating points, I don't see how this is different from just assigning it directly.
  2. Unless you allow the stock parts to have ridiculously high max temps, I doubt this would help. FractalUK modeled radiation using Stefan's Law, so dissipation is proportional to temperature to the fourth power. For example, the upgraded radiators (max 3500 K) require 169 times less area compared to the normal ones (max 970 K) to dissipate the same amount of heat. Wikipedia says 930 K is already "bright orange." At safe temperatures for the stock parts, that could be thousands of times less effective than the upgraded graphene radiators. Some of the stock parts do have high max temps, but I believe those are the ablative type heat shields and not for use as radiators (the heat shields peel off with use).
  3. I was mistaken about the thermal rocket nozzles in the tech tree. That wasn't in CTT, that's in "unofficial KSPI."
  4. Post #552 from the previous thread seems like an oversight. The wiki lists the 2.5m and 3.75m fusion reactors as having deuterium and tritium. https://github.com/FractalUK/KSPInterstellar/wiki/Reactors
  5. @JeffreyCor Dependency to TweakScale started at 0.6.3, I believe.
  6. @Northstart1989 Yeah, I'm not rushing you guys. Just something to take note of. Btw, I think it's time for KSPI Extended to have it's own thread. I kinda feel that you guys are not getting enough attention from users because it's inside here.
  7. I'm getting infinity again. Maybe because of the thermal receiver? Also it seem the old thermal rockets are still in the tech tree (CTT)
  8. Wow. 0.7 indirectly fixed my problems. Good thing I saw the word "resizable" in the features.. I thought TweakScale was optional? It wasn't listed as a dependency on the first page. Oh well.. time to play again.
  9. No idea. I'm not even 100% sure if that's the cause. Could you try to remove that line and see what happens? Hm.. if that's the cause then toggling the propellant should reset the limiter. I'll switch back to windows and test it. EDIT: Yep toggling the propellant resets the limiter. I suppose that was done so that switching to a propellant with a lower thrust doesn't suddenly make you fall to the ground? IMO, the limiter resetting when you go out the launch pad is a bug but resetting when you switch propellants.. could be feature of some sort? Well, your call if this is worth fixing. Worst case that happens when it resets is you have to throttle down. I only found this because I have a 1 terawatt microwave power source and my rockets are exploding if I don't limit the thrust. I could just as easily set the limit on the thermal receivers..
  10. I think I found the cause for the thermal rocket nozzle resetting to 100 thrust limit but it seems like a legacy issue and was not caused by KSPI Extended.. FNNozzleController.cs in setupPropellants myAttachedEngine.thrustPercentage = 100; Probably that. Btw, the alcubierre drive thing was not a graphics issue. It was warping at 45 degree angles.
  11. FreeThinker could you update your github repository? I'll check the changes.
  12. 0.6.3 broke interstellar parts for me. Not sure what to report.. the parts just plain don't work. And about the thermal rocket nozzles, Then in the launch pad it's back to 100
  13. AlcubierreDrive.cs, in ActivateWarpDrive, this change looks suspicious from [COLOR=#0000ff]Vector3d[/COLOR] heading = part.transform.up; [COLOR=#0000ff]double[/COLOR] temp1 = heading.y; heading.y = heading.z; heading.z = temp1; to [COLOR=#0000ff]Vector3d[/COLOR] heading = part.transform.up; heading.y = heading.z; heading.z = heading.y; [COLOR=#00ff00]// I think this does nothing[/COLOR] In the old code, heading.y and heading.z was switched while the newer code sets both to be equal to heading.z (I mean the old value of heading.y was not saved and lost).
  14. Can anyone verify for me if the alcubierre drive is working properly? It's warping at fixed angles in my game. Also, FreeThinker, I think the thermal rocket is ignoring the thrust limiter set at the VAB.
  15. So I tried fixing the plasma engine (yeah this again) UI bug (post #457, I'm experiencing it too).. At ElectricEngineControllerFX.cs, I think the fault is with modifiedEngineBaseISP. It's uninitialized and only assigned at the function OnStart. Does OnStart get called before/at the VAB? I don't know C#, I'm just "grokking" it based on other languages. But based on this: http://blogs.msdn.com/b/abhinaba/archive/2005/11/08/490248.aspx uninitialized variables are set to zero? If I'm correct and it's modifiedEngineBaseISP's fault, this would explain why thrust is infinity and isp is zero. At line 333, [COLOR=#0000ff]double[/COLOR] thrust_per_mw = ([COLOR=#ffd700]2e6[/COLOR] * powerTrustMultiplier) / g0 / modifiedEngineBaseISP / [COLOR=#ffd700]1000.0[/COLOR]; division by zero makes thrust_per_mw infinity which carries on to thrustProp at line 338 and then to the ToString method, I think? Same with ispProp at line 337. I dunno, can't compile it myself since I don't have visual studio installed.
  16. Then I think that's the cause. 0.768 is four times the 0.192 exitArea value of the 1.25m plasma engine. It shouldn't be 90.768.
  17. I thought it's controlled by the exitArea values at part1.cfg and part2.cfg at WarpPlugin\Parts\Engines\MPD? I tried changing the exitArea value for part2.cfg from 90.768 to 0.768 and I get this: When I change it back to 90.768, it's back to 0 thrust. Hey wait, am I the only one having this problem? Were you not able to reproduce it, FreeThinker?
  18. So I was snooping around the source... double actual_max_thrust = Math.Max(max_thrust_in_space - (exitArea * GameConstants.EarthAthmospherePresureAsSeaLevel * part.vessel.atmDensity), 0.0); What's the normal value for atmDensity and the pressure at the launch pad? The value computed for the first argument could've been negative so max is returning zero. The exitArea's for the 1.25m and 2.5m are 0.192 and 90.768 respectively, right?
  19. FreeThinker, the 2.5m plasma engine seems to be bugged. The 1.25 thruster seems fine. Just switched the engines. I just installed KSP-I extended today so this is in 0.6.1.1, I suppose.
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