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[1.12.*] Deadly Reentry v7.9.0 The Barbie Edition, Aug 5th, 2021


Starwaster

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Okay for those of you needing english/laymans terms on the 4 main ingredients to a challenging heating I think I have gotten the definitions down to the letter.

Im going to talk about the 2 pairs of ingredients then elaborate more.....

INPUTS

SHOCKWAVE EXPONENT This is the measure of force thats working against atmosphere. Think of it like going in the back of a pickup while its speeding at 100 mph. The faster its going it exponentially creates a breeze. That breeze is the "shockwave" . So when we talk about shockwave we talk about the opposite , but equal reaction to drag.

SHOCKWAVE MULTIPLER Here we are just using linear values to increase the shockwave exponent we talked about above. Its sort of like increasing throttle in a plane.

Shockwave Exponent + Shockwave Multiplier = INPUTS

OUTPUTS

TEMPERATURE EXPONENT After figuring out the above 2 input ingredients we must talk some sense in how DRE uses that algorithm to generate the actual heat to kill your kerbals. The game has a stock heating system that pretends to do heat when going through re-entry. That above algorithm will raise the stock temps.

HEAT MULTIPLIER Again like the shockwave multiplier, this value just adds more to the exponent. The multipliers are kind of the analog "throttle" to increase difficulty.

Temp Exp + Heat Mult = OUTPUTS

Shockwave Exponent + Shockwave Multiplier = INPUT VALUE + Temp Exp + Heat Mult = OUTPUT aka TEMPERATURE

DEPENDANTS

Density Exponent This value is never really specified so im going to take a stab at it. This is the value which says WHEN the shock heating will take place. The closer to "1" means the heating will start at near full atmosphere. A low value like .4 means that the heating will start a hell of alot higher in altitude. Im curious as to what a value of "0" would be? Shock heating all the way to the moon? LOL

Starwasher, please let me know if im off on something, but I think I have learned a bit experimenting myself at this wonderfull beast of a mod :P

Edited by lextacy
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Dear Starwaster,

Would you please make Deadly Reentry write "Shielded" and "Unshielded" instead of "isShielded: True" and "isShielded: False"? I ask because changing this output would make your mod would become much-prettier. :)

-Duxwing

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Dear Starwaster,

Would you please make Deadly Reentry write "Shielded" and "Unshielded" instead of "isShielded: True" and "isShielded: False"? I ask because changing this output would make your mod would become much-prettier. :)

-Duxwing

That's not Deadly Reentry that's doing that. The only time DRE displays any feedback about 'shielded' is if the debug menu is open and even then it's in the place of the shockwave temperature, where if the part is not exposed to the shockwave at all then it displays 'Shielded'

Sounds like you're a FAR user. That's probably where that's coming from.

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That's not Deadly Reentry that's doing that. The only time DRE displays any feedback about 'shielded' is if the debug menu is open and even then it's in the place of the shockwave temperature, where if the part is not exposed to the shockwave at all then it displays 'Shielded'

Sounds like you're a FAR user. That's probably where that's coming from.

Oh, thanks! :) Time to bug ferram.

-Duxwing

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Curious, how do you find out your entry angle? I've always want to know.

I've been using the formulas on this thread: http://forum.kerbalspaceprogram.com/threads/30311-Calculating-Re-entry-Angle-from-Orbit

IIRC the radius for stock Kerbin the radius is 600000 m + 70000 m for the atmosphere. The other parameters I get from Kerbal Engineer.

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I've been using the formulas on this thread: http://forum.kerbalspaceprogram.com/threads/30311-Calculating-Re-entry-Angle-from-Orbit

IIRC the radius for stock Kerbin the radius is 600000 m + 70000 m for the atmosphere. The other parameters I get from Kerbal Engineer.

I probably should have just asked for periapsis prior to reentry. That's usually all I go by myself when planning my reentry. (for stock Kerbin, a Pe of 20km is usually good enough and 60-80 for RSS sized, i.e. 10x Kerbin or Earth)

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I have a really weird bug, my kerbal is heating up till he explodes, while just sitting on a rover seat. Getting him of the seat stops the heating, but moving the seat and sitting in it again started it all over.

ga48fmi.jpg any clue what might cause this? I like Lony Kerman and I don't want him dead :(

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Okay for those of you needing english/laymans terms on the 4 main ingredients to a challenging heating I think I have gotten the definitions down to the letter.

Im going to talk about the 2 pairs of ingredients then elaborate more.....

INPUTS

SHOCKWAVE EXPONENT This is the measure of force thats working against atmosphere. Think of it like going in the back of a pickup while its speeding at 100 mph. The faster its going it exponentially creates a breeze. That breeze is the "shockwave" . So when we talk about shockwave we talk about the opposite , but equal reaction to drag.

SHOCKWAVE MULTIPLER Here we are just using linear values to increase the shockwave exponent we talked about above. Its sort of like increasing throttle in a plane.

Shockwave Exponent + Shockwave Multiplier = INPUTS

OUTPUTS

TEMPERATURE EXPONENT After figuring out the above 2 input ingredients we must talk some sense in how DRE uses that algorithm to generate the actual heat to kill your kerbals. The game has a stock heating system that pretends to do heat when going through re-entry. That above algorithm will raise the stock temps.

HEAT MULTIPLIER Again like the shockwave multiplier, this value just adds more to the exponent. The multipliers are kind of the analog "throttle" to increase difficulty.

Temp Exp + Heat Mult = OUTPUTS

Shockwave Exponent + Shockwave Multiplier = INPUT VALUE + Temp Exp + Heat Mult = OUTPUT aka TEMPERATURE

DEPENDANTS

Density Exponent This value is never really specified so im going to take a stab at it. This is the value which says WHEN the shock heating will take place. The closer to "1" means the heating will start at near full atmosphere. A low value like .4 means that the heating will start a hell of alot higher in altitude. Im curious as to what a value of "0" would be? Shock heating all the way to the moon? LOL

Starwasher, please let me know if im off on something, but I think I have learned a bit experimenting myself at this wonderfull beast of a mod :P

The various multipliers don't add to any exponents.

shockwave temperature = velocity (m/s) ^ shockwave exponent * shockwave multiplier

part temperature increase (every second) = ((shockwave temp - part temp)^temperature exponent) * (density ^ density exponent) * heat multiplier

Parentheses added for clarity. Final result is powers multiplied by multipliers.

Things get a little more complex when the heat shields are involved but the beta simplifies things a bit by making them behave more like non-heatshield parts in that you will actually see them increase in temperature. (previously ablation was just based on the shockwave which confused people because they would see ablation rates increase even though part temperature was decreasing)

The alternate heating model in the beta

I have Deadly Reentry Beta 6.5.2, as far as I can see on the original post, this is the most recent version?

Ok I need to see your log file. You need to have had the Kerbal on the screen overheating. I need the entire file. Either output_log.txt (Windows) or player.log (Linux / Mac). Zip it up and put it somewhere for download. Use Dropbox preferably, you should have a Dropbox account anyway. You'll thank me later.

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I could use some advice on how to shield stuff. I'm running into a couple different issues, one is that O sometimes lose bits of lander, and another is that I sometimes need both ends of a lander for my existing designs (the one I'm looking at is a duna lander that uses both chutes and its engine for final landing)

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I could use some advice on how to shield stuff. I'm running into a couple different issues, one is that O sometimes lose bits of lander, and another is that I sometimes need both ends of a lander for my existing designs (the one I'm looking at is a duna lander that uses both chutes and its engine for final landing)

Why are you losing bits of lander? Are the bits burning up? There needs to be a shield between those bits and and the shockwave. Look at the part and trace a line along its flight path. If there's a shield in the way then it should be ok as long as the shield itself doesn't burn up.

Parts inside cargo holds or fairings should be ok as well. (with the caveat that parts right in the middle or underneath a seam in the fairing may burn up. Having FAR/NEAR installed increases the probability that the part will be detected as shielded)

Not sure I'm understanding your second point. Ok, so you need an engine. Make sure that you have a shield under the engine until you actually need to fire the engine up. Make sure the shield either has a decoupler builtin or that you put a decoupler between the engine and the shield.

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Playing on 6.4x Kerbol with a freshly downloaded beta of DREC, I tried a reentry using just a Mk1 pod with parachute. My ablative shielding only lost 1 unit before I burned up and exploded. I'm certain I had a good angle for the reentry, and I'm about to launch back up there and try it again to get more details. This time I'll quicksave so I can examine what's going wrong here.

Edit:

To use this in 6.4x Kerbol it seems I need to do either both Alternate heating model and Alternate density calc ticked, or both unticked.

In both cases, however, I'll go through an entire reentry burning off only 1-5 units of ablative shielding from the Mk1 Pod which I think is very unusual considering I almost hit the maxtemp 1250 limit on the pod.

Edited by Nerezza
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I was trying out DR 6.5.2-beta in my BTSM career. All default values (as modded by BTSM). Finding it much hotter than DR 6.3.2, to the point of some rockets needing redesigns and different ascent paths to avoid having the forward parts burn up. And I can't reenter a Mk1 pod from an equatorial orbit.

Mk1 pod reentry 90x27km ellipse. Lost all 250 units of heatshield between 65km and 37km, Mk1 destroyed moments after last bit of heatshield gone. Output_log.txt here.

Switched to DR 6.4.0, again all default. Same reentry. Lost 136 units of heatshield between 41km and 19km, Mk1 survived. Output_log.txt here.

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I was trying out DR 6.5.2-beta in my BTSM career. All default values (as modded by BTSM). Finding it much hotter than DR 6.3.2, to the point of some rockets needing redesigns and different ascent paths to avoid having the forward parts burn up. And I can't reenter a Mk1 pod from an equatorial orbit.

Mk1 pod reentry 90x27km ellipse. Lost all 250 units of heatshield between 65km and 37km, Mk1 destroyed moments after last bit of heatshield gone. Output_log.txt here.

Switched to DR 6.4.0, again all default. Same reentry. Lost 136 units of heatshield between 41km and 19km, Mk1 survived. Output_log.txt here.

Thanks but logs are only really useful in tracking down errors.

It would be more useful for me to know what your settings are and how they differ from defaults. it should be really hard for you to burn anything up on ascent now.

Unless you're not using the new heating model. (Says Alternate and it should be enabled by default except that I think BTSM changes DRE defaults?)

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Thanks but logs are only really useful in tracking down errors.

It would be more useful for me to know what your settings are and how they differ from defaults. it should be really hard for you to burn anything up on ascent now.

Unless you're not using the new heating model. (Says Alternate and it should be enabled by default except that I think BTSM changes DRE defaults?)

Definitely burned up a Mk1 pod on ascent. The rocket was slightly underrated. Used MechJeb's Ascent Guidance which didn't handle the underrating well and the prograde vector was below what MJ wanted. Was just over 42km with speed getting over 1200m/s. Shortly after that the Mk1 was destroyed. This one I solved by upgrading the 1st stage to avoid that high speed at that low altitude.

All these are the defaults, taken from the DR settings and debug windows in flight.


On Use Legacy Aerothermodynamics
Off Alternate Density calc (ignores densityExponent)

1 Shockwave Multiplier
1.09 Shoctwave Exponent
1.03 Temperature Exponent
0.85 Density Exponent
25 Multiplier
F/X Transition
Begin at 750 m/s
Full at 1150 m/s
0.8 FX Density exp
2.5 G Tolerance Mult
0.5 Parachute Temp Mult
30 Crew G Max
4 Crew G Exponent
5 Crew G Min
300000 Crew G Warn Level
600000 Crew G Kill threshold
0.75 Crew G Kill chance per update

Note that DR 6.5.2's windows still say "Deadly Reentry 6.4.0".


On Use Legacy Aerothermodynamics
Off Alternate Density calc (ignores densityExponent)
On Alternate Heating Model
On Warn when it is unsafe to deploy parachutes due to heating
On Warn when crew are experiencing hazardous levels of g forces

1 Shockwave Multiplier
1.09 Shoctwave Exponent
1.03 Temperature Exponent
0.85 Density Exponent
25 Multiplier
F/X Transition
Begin at 750 m/s
Full at 1150 m/s
0.8 FX Density exp
2.5 G Tolerance Mult
0.5 Parachute Temp Mult
30 Crew G Max
4 Crew G Exponent
5 Crew G Min
300000 Crew G Warn Level
600000 Crew G Kill threshold
0.75 Crew G Kill chance per update

I tried a test of DR 6.5.2 with a Mk1 pod reentry 20km periapsis from a 90km polar Kerbin orbit, a bit hotter than that from an equatorial prograde orbit. Default performed about the same as before, all heatshield ablated from 65km to 38km, when the Mk1 was destroyed.

I then turned off Alternate Heating Model. This was a bit hotter than 6.4.0 but the Mk1 survived, ablating from 48km to 14km, leaving 68/250 units of heatshield.

Edited by Jacke
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Set the first 4 to 1 and leave them there. Set Multiplier to 10-20. (probably 10... the build I'm working with is a bit different where I'm working with values much higher but that would be suicide with the build that's up for download right now)

Edited by Starwaster
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Set the first 4 to 1 and leave them there. Set Multiplier to 10-20. (probably 10... the build I'm working with is a bit different where I'm working with values much higher but that would be suicide with the build that's up for download right now)

DR 6.5.2 BTSM 01.6600, set

 
On Use Legacy Aerothermodynamics
Off Alternate Density calc (ignores densityExponent)
On Alternate Heating Model
On Warn when it is unsafe to deploy parachutes due to heating
On Warn when crew are experiencing hazardous levels of g forces

1 Shockwave Multiplier
1 Shoctwave Exponent
1 Temperature Exponent
1 Density Exponent
10 Multiplier

Mk1 pod Kerbin polar orbit 90km, reentry initial periapsis 20km. Ablation started about 56km. About 18km Heatshield 0/250 units, speed about 1000m/s, destruction of Mk1.

Tried that again, with 5 Multiplier. Ablation started about 50km. About 17km Heatshield 113/250 units, speed about 1000m/s, but temperature 1161C, destruction of Mk1.

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DR 6.5.2 BTSM 01.6600, set
 
On Use Legacy Aerothermodynamics
Off Alternate Density calc (ignores densityExponent)
On Alternate Heating Model
On Warn when it is unsafe to deploy parachutes due to heating
On Warn when crew are experiencing hazardous levels of g forces

1 Shockwave Multiplier
1 Shoctwave Exponent
1 Temperature Exponent
1 Density Exponent
10 Multiplier

Mk1 pod Kerbin polar orbit 90km, reentry initial periapsis 20km. Ablation started about 56km. About 18km Heatshield 0/250 units, speed about 1000m/s, destruction of Mk1.

Tried that again, with 5 Multiplier. Ablation started about 50km. About 17km Heatshield 113/250 units, speed about 1000m/s, but temperature 1161C, destruction of Mk1.

A steeper reentry will get that pod down safely.

Are you still having overheating trouble on the ascent?

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