What can I do to manage heat generation?

[BurningLegion]

So I have a question. How do I deal with heat? Or more specifically, what mechanics influence the distribution of heat, and what can I do from a design perspective to encourage the radiation of heat?

The story behind my question is, I suspect, fairly typical. I got a testing contract for the LV-N (Guess what contract allowing access to a part that requires a whole research all to itself is never going to be completed?), and after some trial and error, fitted it on a Mun rocket as a personal trial for the system in a way that gained me 2k Delta V from dropping Oxidizer.

I note that TWR is low, even compared to Munar gravity, so I prepare for a long burn. After I burned for a while, I notice that my probe core is overheating, as well as some other things.

I did see some of the LV-N overheating threads, and I want to be clear: I don't think there's a problem with the engine. Given that just mounting it gained me 2k Delta-V and I had to fire at maximum thrust for three minutes in a ship with no crew to get this result, it seems like a fair trade. What I'm interested in is how I can control what components overheated first - I had to complete my burn at 5% power so I didn't explode the probe core. The components overheated in this order: Probe Core, Decoupler, LV-909(next stage), fuel tank, LV-N. When the Probe Core turned red is when I stopped burning.

I know the different components have different overheat tolerances - I suspect the Probe Core started complaining first because it had the lowest tolerance, but I'm pretty sure the fuel tank & decoupler have the same tolerance, which makes it interesting that the decoupler (which is further away) started overheating first.

I've had similar experiences with heat while using Mainsail engines & Kerbodyne liquid fuel boosters, but this is the most extensive example. From a design perspective, what can I do to influence heat management?

Edited May 24, 2015 by BurningLegion
Answered!

[Gaarst]

Fuel tanks are excellent heat sinks as their thermal mass is very high: they can absorb a lot of heat without getting too hot. Smaller parts require less energy to increase in temperature so they will heat faster.

A good way to manage heat is to put you engine right next to a big fuel tank (full is better) and add radiative parts (wing parts work well) if necessary.

[Wanderfound]

See http://forum.kerbalspaceprogram.com/threads/121835-Cooling-LV-N-Nervas-it-s-not-rocket-science

TLDR version: connect your heat-makers close to parts with high heat capacity and lots of surface area. Fuel tanks and fins is one way to do it.

Edited May 23, 2015 by Wanderfound

[BurningLegion]

Thank you both! Especially for linking me to that thread. The next iteration will use the lessons of that thread. Based on reading it, the fuel tank was overheating less because it had a larger surface area, and the only reason heat was traveling forward up the rocket is because there wasn't enough to vent it at the source of generation. This is giving me a lot of good ideas for a long-range ship.

Maybe if I put the fins on a central fuel tank the engine and command pod are attached to, then arrange extra fuel tanks radially so they can be dumped as they're emptied, I can keep Delta V high enough to make an actual there & back again journey.

[Red Iron Crown]

You can also use a heatshield between the "hot" section of your craft and the "cold" section, this slows conduction enough to allow your wings radiators to do their job without too much heat making it to more sensitive components.

[KingMonkeyNuts]

http://forum.kerbalspaceprogram.com/threads/118189-1-0-2-Heat-Management-Radiator-emissives-and-tracking-update-%280-23-19-5-15%29

Try this mod. It does things with heat. I'm not entirely sure what it's doing, but it is doing something.

[Streetwind]

http://forum.kerbalspaceprogram.com/threads/118189-1-0-2-Heat-Management-Radiator-emissives-and-tracking-update-%280-23-19-5-15%29

Try this mod. It does things with heat. I'm not entirely sure what it's doing, but it is doing something.

It has special parts that have their thermal stats chosen in a very specific way to make them able to passively ingest and dissipate large amounts of heat. You put them between your hot engine and the rest of the ship. The heatsink makes sure that little heat flows to the rest of the ship but a lot of heat flows to the attached radiators.

<Activate Shameless Advertising Module>

If you'd like something a bit more high tech and high performance, Nertea is currently putting the finishing touches on the update of the Near Future Electrical pack (see sig). The radiators included in that pack will take some research effort, but in return they have active cooling capabilities.

Release will be not long after KSP 1.03 hits... which, if Squad is to be believed, should be any day now.

[Randazzo]

http://forum.kerbalspaceprogram.com/threads/118189-1-0-2-Heat-Management-Radiator-emissives-and-tracking-update-%280-23-19-5-15%29

Try this mod. It does things with heat. I'm not entirely sure what it's doing, but it is doing something.

It's pretty simple. Using stock mechanics, there are two options available:

1. Heat Sinks - High thermal mass, low conductivity. Soaks a boatload of heat from the nuke, and although it still transfers to the rest of the ship, it's done much more slowly than usual. Add some radiators to help dissipate the heat. The same effect can be gotten through stock by using a large, heavy fuel tank and wing parts.
   
2. AHMS Units - Active Heat Mangement System. Works the same as Red Iron Crown's heatshield suggestion. The main difference is that the AHMS units have a replenishable resource (consumes electricity to do so).
   

If you'd like something a bit more high tech and high performance, Nertea is currently putting the finishing touches on the update of the Near Future Electrical pack (see sig). The radiators included in that pack will take some research effort, but in return they have active cooling capabilities. .

The AHMS units function both passively and actively.

Edited May 23, 2015 by Randazzo

[BurningLegion]

Thanks everyone who responded! I've downloaded the heatsink mod because the Near-Future spaceships forum post is making my head spin and I should probably actually land on at least one non-Kerbin non-Mun planet before I go for that kind of modding difference. But right now I'm working on a design that uses 8 Delta Wings around a fuel tank next to a heatshield, because I haven't actually researched nuclear propulsion I only have the LV-N for a testing contract, so I'll get to try it both ways.

One last question: How do I change this thread to "Answered"?

[FancyMouse]

One last question: How do I change this thread to "Answered"?

Nobody reads sticky:rolleyes:

[BurningLegion]

Nobody reads sticky:rolleyes:

Then I hope they at least post reasonably helpful things or learn awesomeness from the epic replies in this thread. Hi everyone!

[Randazzo]

One last question: How do I change this thread to "Answered"?

Edit your original post. Click "Go Advanced". Change the prefix there to Answered. You don't have to change anything else.