Exhaust stream doesn't heat anything ... why?

[Azimech]

I saw that with 1.0.4 the rocket and jet engines heat up, but won't produce heat to the parts they hit. Is this temporary? Why has Squad chosen this approach?

A small joke, but as you can see, it not only blows.

[Godot]

Because, from a provgramming standpoinmt, it would take up too much system ressources to also simulate the heat flows emanating from an engine?

[Gargamel]

It used to heat stuff up, or at least damage parts. It's something that was removed.

[Azimech]

It still damages stuff, but they don't use the damage flag for anything.

[klgraham1013]

It still damages stuff, but they don't use the damage flag for anything.

I forgot about the damaged flag. Another piece of legacy code they can remove with the upgrade to Unity 5.

[Sharpy]

The heat appears only a considerable distance from the engine. You can still burn stuff away, but the engine must be placed quite a bit away from what is to be burned.

[Grumman]

If nothing else, nuclear rocket exhaust does cause heating in 1.0.4.

[Geschosskopf]

The heat appears only a considerable distance from the engine. You can still burn stuff away, but the engine must be placed quite a bit away from what is to be burned.

The heat also only comes from direct flame impingement in line with the direction of thrust. The radiant heat that in real life would be thrown out in all directions to the sides of the flames is ignored completely. This is what allows "puller" rockets to work safely despite flames licking all down their sides. Many folks use "puller" rockets as a way to avoid wobbles and probably don't realize it's really an exploit, but OTOH the wobbles are silly anyway so.......

[Guest]

I saw that with 1.0.4 the rocket and jet engines heat up, but won't produce heat to the parts they hit.

We've had this discussion before, exhaust heats up parts just fine. The problem is that rocket exhaust isn't as hot as you think (compared to chamber temperature, at least) and parts in KSP have ridiculous temperature tolerances.

E: Here's the previous discussion.

A few things to keep in mind:

Skin heating has to transfer to core heating before a part blows up.

Parts will offload heat to neighboring parts if they can.

A Stayputnik can tolerate over 1600K, almost the melting point of wrought iron.

A Rocketdyne F1's exhaust temperature is roughly 1750K, the SSME around 1250K.

Reentry temperature is much higher than engine exhaust, almost four times hotter.

If anything, KSP is doing pretty good on the engine exhaust (with a single raycast, sure, but let's remember how bad KSP's performance is), it's just that the parts are ridiculously OP.

Edited July 11, 2015 by regex

[FancyMouse]

The video doesn't look like heat - it's just air blowing off snow, not heating them up.

[Azimech]

We've had this discussion before, exhaust heats up parts just fine. The problem is that rocket exhaust isn't as hot as you think (compared to chamber temperature, at least) and parts in KSP have ridiculous temperature tolerances.

It's not a matter of how hot I think the gases are, I'm already happy with an increase of 1 deg, because I'm looking for some way to have a switch. The single raycast is perfect, but since I can't use the force to switch, I must use temperature. Using the seebeck mod, I can create electricity out of temperature differential, and therefore I'm busy with creating a simple electronics mod.

But ... I'll need to test then at what distance heating does start.

E: Here's the previous discussion.

A few things to keep in mind:

Skin heating has to transfer to core heating before a part blows up.

Parts will offload heat to neighboring parts if they can.

A Stayputnik can tolerate over 1600K, almost the melting point of wrought iron.

A Rocketdyne F1's exhaust temperature is roughly 1750K, the SSME around 1250K.

Reentry temperature is much higher than engine exhaust, almost four times hotter.

If anything, KSP is doing pretty good on the engine exhaust (with a single raycast, sure, but let's remember how bad KSP's performance is), it's just that the parts are ridiculously OP.

Agreed. By the way, did you know you can modify a rocket engine to have a negative heat production? A jet blast which cools.