1.4, how do I cool the Nerva engine?!?!

[Loren Pechtel]

This is driving me nuts.  I'm trying to send a scientific mission to orbit the moons.  On 1.2 I had no problem, slap a few radiators on and it works fine.  Now, however, I have yet to come up with anything.  I've attached every radiator I have to the fuel tank above the engine, they accomplish almost nothing--a few hundred watts of heat per radiator. 

I think something must have changed in the physics.

[Gordon Fecyk]

I've read elsewhere that on-rails time warp messes with the thermal model considerably. Fortunately, while you're accelerating with LV-Ns, you can only use physics warp. The LV-Ns used to put out a lot more heat than they do today, but I have had thermal issues pushing large asteroids around.

The simplest solution is to add more radiators to your craft. One design I built borrows from one of the stock scenario missions (look up the Jool Aerocapture scenario in-game). It attaches some radial-mounted radiators to Mk1 liquid fuel-only tanks and the LV-Ns attach to those.

If you wanted to get clever, you could drag the radiators so that they appear to cover the LV-Ns:

The radially mounted radiator panels will only cool the part they are directly attached to and one part past that. In these examples that means the fuel tank it's directly attached to, and both the first tank it attached to plus the LV-N attached to it. You can't attach anything radially to the LV-N itself, but this is an acceptable workaround.

Note that all radiators require electric charge to work, so make sure you have batteries and a source of electric charge. The LV-Ns themselves generate electric charge so that counts.

Edited November 28, 2018 by Gordon Fecyk
Grammar

[Loren Pechtel]

I guess I need to unlock another level of cooling.  I don't have those yet.

[Foxster]

I just don't have any heating problems with nukes these days, including for crafts with long burns to places like Eeloo. 

Could you post a pic of your craft?

[Loren Pechtel]

On 11/27/2018 at 7:51 PM, Gordon Fecyk said:

I've read elsewhere that on-rails time warp messes with the thermal model considerably. Fortunately, while you're accelerating with LV-Ns, you can only use physics warp. The LV-Ns used to put out a lot more heat than they do today, but I have had thermal issues pushing large asteroids around.

The simplest solution is to add more radiators to your craft. One design I built borrows from one of the stock scenario missions (look up the Jool Aerocapture scenario in-game). It attaches some radial-mounted radiators to Mk1 liquid fuel-only tanks and the LV-Ns attach to those.

If you wanted to get clever, you could drag the radiators so that they appear to cover the LV-Ns:

The radially mounted radiator panels will only cool the part they are directly attached to and one part past that. In these examples that means the fuel tank it's directly attached to, and both the first tank it attached to plus the LV-N attached to it. You can't attach anything radially to the LV-N itself, but this is an acceptable workaround.

Note that all radiators require electric charge to work, so make sure you have batteries and a source of electric charge. The LV-Ns themselves generate electric charge so that counts.

Things get stranger and stranger.

I unlocked the graphene radiators, put 4 large ones on (there's one Nerva engine) and tried it.

Things finally appear to be stable, each radiator is dumping 20kw of power.  However, they are showing:

Rad Temp: 199.6K/2698K

Part Temp: 1507.1K/2698K

Core temperature: 1507/1210K

Skin temperature: 1331/1210K

What's really going on with the heat?  1507.1K/2698K looks fine but what are the other temperatures?  1507/1210K should go boom but it's flying fine.

(And why do the pesky things want to deploy on the pad?)

[Starwaster]

21 minutes ago, Loren Pechtel said:

Things get stranger and stranger.

I unlocked the graphene radiators, put 4 large ones on (there's one Nerva engine) and tried it.

Things finally appear to be stable, each radiator is dumping 20kw of power.  However, they are showing:

Rad Temp: 199.6K/2698K

Part Temp: 1507.1K/2698K

Core temperature: 1507/1210K

Skin temperature: 1331/1210K

What's really going on with the heat?  1507.1K/2698K looks fine but what are the other temperatures?  1507/1210K should go boom but it's flying fine.

(And why do the pesky things want to deploy on the pad?)

That's for the core temperature. The 1210 isn't a maximum, it's the optimum temperature for core. Core temperature  is not checked at all for part destruction. Depending on how the core is set up it may shut down certain modules but it will never destroy the part. It will leak heat to the part but generally not enough to destroy the part. (depends on how it's configured)

btw it is not stock behavior for Nerv to utilize core heat.

Edited November 30, 2018 by Starwaster
fixed spelling

[Loren Pechtel]

23 minutes ago, Starwaster said:

That's for the core temperature. The 1210 isn't a maximum, it's the optimum temperature for core. Core temperature  is not checked at all for part destruction. Depending on how the core is set up it may shut down certain modules but it will never destroy the part. It will leak heat to the part but generally not enough to destroy the part. (depends on how it's configured)

btw it is not stock behavior for Nerv to utilize core heat.

No--those numbers are from the radiator, not the engine.

[Starwaster]

8 minutes ago, Loren Pechtel said:

No--those numbers are from the radiator, not the engine.

Ok, even so. What I said still applies. If it's core temperature then it isn't checked for part destruction. There isn't even a maximal value for core temperature, only a target temperature that if it is not met or is exceeded then core heat dependent modules will run inefficiently.