[1.0.2] Re-entry heating rebalance (made harder) & heatshield conduction fix (v.1.1)

[DJK]

-- This mod is no longer maintained. Since 1.0.4 update, it is very easy to tweak the reentry thermal effects and this mod is no longer needed. Thank you.

Hello.

The following file address two issues with 1.0.2 re-entry thermal effects.

#1 - Stock re-entry in 1.0.2, even at 120% difficulty does NOT require a heat shield. Simply put.. nothing explodes and re-entering without a heat shield is perfectly safe.

To me that seems extremely broken & unrealistic. And i'm sure there are many people who agree.

A simple tweak in the Physics.cfg file fixes that.. making your re-entries actually dangerous.

Currently, i've set it so that you will be able to re-enter with a command pod & parachute attached (without heat shield) from LKO (100km) with a decent re-entry trajectory.

Anything beyond that and you're gonna have a nice fireworks display.

That in turn rendered the stock heat shields useless.. which have been balanced as well. They work roughly as stock, but are balanced for the more dangerous re-entry.

#2 - Stock heat shields have a major issue, in which when they run out of ablator, they stop conducting heat to whatever is attached to them making it practically immune to re-entry heat conduction between parts as long as the heat shield is attached (can't believe no one noticed this).

Fixed.

Additional Info:

Tests were conducted for balance purpose up to interplanetary re-entry coming from Duna with heat shields.. roughly 3800 m/s speed and they will protect your command pods and kerbals. Go higher than that.. and who knows what might happen

SSTO's ARE able to reach orbit & re-enter, even if the heat is more intense, you just need to watch it carefully. I'd say it is a bit more harder to manage them now.

Ascending rockets are harder as well. You need to watch that speed during lower altitudes! Note that some parts that have low max temperature might or might not blow up (like the basic fin, for example).

What the actual file does:

Changes "convectionVelocityExponent" value (originally found in Physics.cfg) from 3 to 3.35 (can be changed to suit your needs)

Rebalances "Ablator" resource "hsp" value & heat shields thermal mass to actually be able to conduct heat to other parts when "Ablator" is 0 (might need rebalance if "convectionVelocityExponent" is not 3.35)

Installation:

Make sure you have your thermal re-entry effects in options set to 120%

Copy the "reentry_heat_rebalance_and_heatshield_conduction_fix.cfg" to your KSP/Game Data directory

Dependencies:

These tweaks need Module Manager 2.6.3 in order to work. You can find it here: http://forum.kerbalspaceprogram.com/threads/55219-1-00-Module-Manager-2-6-2-%28Apr-29%29-Bonsai-Trimming-Kit-Edition

--

Download

Release under MIT License

Enjoy!

--

Changelog:

Version 1.1: Tweaks now use module manager exclusively. No more file overriding needed. Make sure you use module manager 2.6.3.

Version 1.0: Initial Release

Edited June 30, 2015 by DJK

[Lucius]

Until all this nonsense is fixed up by Squad, this should be interesting to test out. Trying now, thanks

[DJK]

No problem. If the heat is too much for your taste (specially for SSTOs), you can lower the convectionVelocityExponent in the Physics.cfg from 3.35 to whatever you'd like. Default was 3, and it is a very sensible value. Even lowering it to 3.32 makes a noticeable difference. If you do lower it by a small amount, the shields could work fine without re-balancing them, only that they would be more effective

Edited May 4, 2015 by DJK

[regex]

So far I've found that these settings are resulting in a 1.25m heatshield under a Mk1 pod + parachute will result in almost 0 ablator left over after reentry from a 75 x 75km orbit using an 18.5km perisapsis. The pod without shield can survive it but it gets pretty toasty, which should be fine for early career. I've been playing with this for a night and need further testing, most especially with spaceplanes, but using a drag multiplier of 7 is a good compromise between pods and aircraft (8 is right for blunt bodies, 6 is right for aircraft.)

dragMultiplier = 7
dragCubeMultiplier = 0.1
angularDragMultiplier = 2
liftMultiplier = 0.055
liftDragMultiplier = 0.025
bodyLiftMultiplier = 10.7
aeroFXStartThermalFX = 2
aeroFXFullThermalFX = 3.5
aeroFXExponent = 3
thermalMaxIntegrationWarp = 100
spaceTemperature = 4
solarLuminosityAtHome = 1360
solarInsolationAtHome = 0.150000005960464
convectionDensityExponent = 1
convectionVelocityExponent = 3.25
newtonianConvectionFactorBase = 2
newtonianConvectionFactorTotal = 3
newtonianVelocityExponent = 0
convectionFactorSplashed = 300
fullConvectionAreaMin = -0.2
fullToCrossSectionLerpStart = 0.8
fullToCrossSectionLerpEnd = 1.5
machConvectionStart = 2
machConvectionEnd = 3 // 4
machConvectionExponent = 2 // 3
partEmissivityExponent = 4
radiationFactor = 1
convectionFactor = 40
conductionFactor = 10
internalHeatProductionFactor = 0.03
aerodynamicHeatProductionFactor = 1.0
standardSpecificHeatCapacity = 800

In the hopes that it will be useful.

Also, you'll really need to try entering Eve's atmosphere with these settings, something else I'll be testing with the above setup in the future. So far, so good, though.

[rkman]

According to this post by NathanKell fullConvectionAreaMin must have its sign flipped; change fullConvectionAreaMin = 0.2 to fullConvectionAreaMin = -0.2

http://forum.kerbalspaceprogram.com/threads/119108-Overhauls-for-1-0?p=1900060&viewfull=1#post1900060

[DJK]

regex, are you using the module manager cfg file for the heat shields that i provided? or just stock shields?

With the files i provided you can do an interplanetary re-entry/aerocapture returning from Duna.. all the ablator is used up but the pod is ok.. seemed like a good compromise for what i needed between fun & realism, even if entering other planets atmosphere could be devastating.. thats where the you'd need to do it "the kerbal way".. so to speak

[regex]

regex, are you using the module manager cfg file for the heat shields that i provided? or just stock shields?

1.0.2 stock shields.

[himnhouw]

Seems this line in ModuleAblator is responsible for the changing conductivity during reentry: reentryConductivity = 0.01

Seems strange to have it change conductivity like that. The default conductivity should to be 0.12. I didn't actually find where that is defined but plenty of Squad's cfgs have comments saying 0.06 and 0.04 are 1/2 and 1/3 default value.

Also AFAICT, the values for aero drag don't actually influence heating in any way. Which is nice so we can tweak them independently.

[regex]

Also AFAICT, the values for aero drag don't actually influence heating in any way. Which is nice so we can tweak them independently.

More drag means an object will slow faster, which means less aerodynamic heating overall. The converse is also true. You cannot separate drag from heating.

[DJK]

1.0.2 stock shields.

Stock shields:

#2 - Stock heat shields have a major issue, in which when they run out of ablator, they stop conducting heat to whatever is attached to them making it practically immune to re-entry heat conduction between parts as long as the heat shield is attached

To confirm, just did an eve re-entry with full stock shields - without my fix but with increased convectionVelocityExponent (just to get them to reach 0 ablator).. pod never heated up past 309 deg. once the ablator reached 0.

EDIT:

https://www.youtube.com/watch?v=x5WQkqpILH8

Edited May 4, 2015 by DJK

[regex]

Stock shields:

vOv

I mainly posted because I thought you might be interested in the settings for additional experimentation and tweaking.

[DJK]

Indeed, they are helpful, thank you. Just wanted to point out the shield conduction issue since you said you'll be testing with the setup you mentioned.

[tjoreilly]

Thanks for putting this out there. These config changes are great. Exactly the reentry heat behavior I've been trying to get.

[jordanjay29]

Umm, can we package this as a mod instead of as a way to overwrite files? Surely even core files can be overloaded with mods, no?

[DJK]

I'm sure a plugin is doable.. but i'm not familiar with KSP modding.. so i lack the knowledge to make one from scratch. If someone wants to do so, be my guest.

Two reasons why i didn't even try.. 1st, the physics.cfg file is the same as the default one with just one value changed.. so its more like a tweak.. and everyone can do it, except that i took the time to fiddle around with multiple settings, see what works and whatnot. In this case, tweaking just that value & re-balancing the heat shields/ablator resource did the trick. This also ensures people can tweak it to their liking.. if they deem it necessary. And 2nd, these files might be obsolete in the very near future when/if SQUAD decides to fix the issues.

[White Owl]

Use JSGME to install all mods, and never worry again about overwriting anything.

[Beetlecat]

Umm, can we package this as a mod instead of as a way to overwrite files? Surely even core files can be overloaded with mods, no?

Module Manager now supports direct override of the physic .cfg file! These fixes can be applied w/o overwriting the stock game file.

[Errol]

Module Manager now supports direct override of the physic .cfg file! These fixes can be applied w/o overwriting the stock game file.

I would be comfortable with using something distributed like this.

[DJK]

Updated to version 1.1. The tweaks now use module manager exclusively.. no more file overriding needed. Please make sure to use module manager 2.6.3

Thank you.

Edited May 5, 2015 by DJK

[jordanjay29]

Updated to version 1.1. The tweaks now use module manager exclusively.. no more file overriding needed. Please make sure to use module manager 2.6.3

Thank you.

Wonderful! Going to download it now.

[Astrospeak]

I've got to say, your tweaks make the 1.0.2 aero perfectly deadly! Re-entry is scary, but not impossible. I hope whatever the devs end up doing with 1.0.3 feels the same…

[vardicd]

Could you tell us how you changed the conduction not working after the ablator runs out? In case we want to play with the settings ourselves?

[ZobrAA]

Are you sure @PHYSICSGLOBALS tweaks works? I've tried to use this method for aerodynamics fix from http://forum.kerbalspaceprogram.com/threads/118633 and it didnt work...

[DJK]

@vardicd - I gave them thermal mass. See line #8 in my module manager file: "thermalMassModifier". They had next to none by default. SQUAD removed it in favor for the ablator. Next i re-balanced the ablator resource hsp to work with the new thermal mass of the heat shields as close as possible as the default values did.

@ZobrAA - PHYSICSGLOBALS does indeed work.. You need to have the actual module manager config file in KSP/Game Data though, not in the main KSP folder. You also need to use module manager 2.6.3. You could clear the module manager cache though, see if that helps.

[vardicd]

How does this affect the larger heat shields? the 2.5 one had 800 ablator, and the 3m one had 1800 do they need to be tweaked? and does anyone know what the line bulkhead size refers too?