13 replies to this topic

[Twilight Fenrir]

This may seem like an obvious question at first glance... but it's really not.

How are heatsinks supposed to work in the Battletech universe?

Everything I can find description of, they work like radiators in a car. Hot coolant passes through an intricate lattice work designed to maximize surface area and dissipate heat.

The problem with this idea... is that it would not work in a vacuum. With no atmosphere to conduct the energy away, the fusion engine alone would overheat, and eventually straight up melt the mech.

So, they must function by a different mechanism...

It's conceivable that they have an 'open' system. That they just straight up boil off the coolant. But this would leave them with a finite supply. This might be supported by the existence of 'Coolant Trucks', which I cannot fathom the need for in any other arrangement. This might also explain why heatsinks weigh an entire ton, if it's a coolant reservoir...

But there are constant references to energy-based mechs being able to remain without supplies indefinitely, provided they remain mechanically operational. So, it kind of shoots a hole there...

I'm aware the clans developed a Laser-based heatsink for the Night Gyr.... which also completely baffles me on how it is supposed to work...

Anyone know the answer to this one?

Thanks!

[Metus regem]

1980's SciFi..... All you need to know.

[Bloodweaver]

Twilight Fenrir, on 16 March 2015 - 06:28 PM, said:

I'm aware the clans developed a Laser-based heatsink for the Night Gyr.... which also completely baffles me on how it is supposed to work...

Anyone know the answer to this one?

Heat and light are different wavelengths of the same thing. So the idea is that those heat sinks convert that infrared "light" (aka heat) into wavelengths within the visible spectrum, giving off a light show. Just silly "rule of cool" stuff

[Corbenik]

"Space Magic"

Edited by Corbenik, 16 March 2015 - 08:07 PM.

[Karl Streiger]

Hey I got used to think about heat sinks as energy grid.

The reactor produces energy to move the Mech an recharge the weapons.
Moving Mech alone doesn't generate much heat - firing weapon on the other hand.... well of course there is some waste heat - Lasers are supposed to have a very low efficiency - creating more waste heat than "light" (maybe stuff is different)

so it could be possible that surrounding energy banks and connectors got more electrical resistance (simple stuff don't know the real thing) - so the reactor need to produce more energy to recharge the system and overcome the temporary increased electrical resistance.

When you need more energy than you can have - the engine takes what it can get (reduced energy for movement - emergency energy for sensors and life support)

It doesn't explain the chance for ammunition explosion or the "cold" gauss - that doesn't make sense even when you think about heat sinks - as heat sinks.

[timaeus]

Twilight Fenrir, on 16 March 2015 - 06:28 PM, said:

This may seem like an obvious question at first glance... but it's really not.

How are heatsinks supposed to work in the Battletech universe?

Everything I can find description of, they work like radiators in a car. Hot coolant passes through an intricate lattice work designed to maximize surface area and dissipate heat.

The problem with this idea... is that it would not work in a vacuum. With no atmosphere to conduct the energy away, the fusion engine alone would overheat, and eventually straight up melt the mech.

Except they don't work like radiators in a car. Despite the name they actually are supposed to work more like futuristic heat pumps. Which is more like an AC unit (with their vacuum compression pumps) than a car radiator.
http://www.sarna.net/wiki/Heat_Sink

I think a heat pump could still work in a vacuum, buuuut not nearly as efficiently as on a planet with and atmosphere since there's not really an effective medium to transfer the waste heat to so you're probably still going to be glowing like the filaments in a toaster at the end.

[Twilight Fenrir]

Karl Streiger, on 16 March 2015 - 11:25 PM, said:

It doesn't explain the chance for ammunition explosion or the "cold" gauss - that doesn't make sense even when you think about heat sinks - as heat sinks.

I dunno... I always thought ammo explosions was fairly self explainitory...

As for the Gauss... It really should produce heat. Electro-magnets generate quite a bit of heat, as they are basically short circuits... Especially one of that power... I always thought Gauss rifles should go into an energy hardpoint on mechs.... Presumably, energy hardpoints have bigger power cables running to them than ballistic hardpoints...

Edited by Twilight Fenrir, 17 March 2015 - 05:52 AM.

[Skylarr]

I am sure there are many who can try to describe exactly how they work. Just use any search engine.

http://www.sarna.net/wiki/Heat_Sink
http://bg.battletech...sinks-in-space/
http://rt000pui.eres...ooling_sys.html

It is just a game. So people are just using current day knowledge to give answers. It is suppose to be several hundred years in the future so some of the exact information on how the Tech works is just using your imagination.

[Twilight Fenrir]

Skylarr, on 17 March 2015 - 06:55 AM, said:

I am sure there are many who can try to describe exactly how they work. Just use any search engine.

http://www.sarna.net/wiki/Heat_Sink
http://bg.battletech...sinks-in-space/
http://rt000pui.eres...ooling_sys.html

It is just a game. So people are just using current day knowledge to give answers. It is suppose to be several hundred years in the future so some of the exact information on how the Tech works is just using your imagination.

Huh... I treid to search for heat sinks on Sarna and got nothing...

A lot of sci-fi tech is based on extrapolation of existing technology... So I was curious if heat sinks had an explainable mechanism, or if they were just 'future tech'.

The Sarna article delves into it better than anything I've seen... But there still is no mention of non-atmospheric functionality.

So, it seems it's just convenience future tech at this point...

Thanks!

[Skylarr]

Does this help you at all?

Quote

In the real world, the thermal rejection systems (or radiators) on satellites radiate heat (infrared photons) into space, just like the Sun delivers energy to the Earth via radiation (photons of varying wavelengths). Think of a solar array in reverse. Here's an example from the International Space Station:

http://en.wikipedia...._Control_System

That's different from conduction/convection (atoms bouncing into each other to transfer energy), which is how your refrigerator or air conditioner works to reject heat into the Earth's atmosphere.

In the BattleTech universe, either the heat sinks on aerospace units are different from the heat sinks on ground units, or they have dual functionality, i.e., an ability to radiate heat in a vacuum _and_ transfer heat in an atmosphere equally well. I don't think anything in the canon has ever elucidated this, but someone else may know better. Would be interesting to know if you could repair a mech with a fighter's heat sink and vice versa.


Regardless, looking at TRO pix, the aerospace heat sinks in BattleTech must be remarkably compact compared to the large exposed surface area required of radiators on real-world satellites. They've apparently made huge advances in heat management materials and efficiencies since the 20th/21st centuries, even though other technologies have remained relatively stagnant.

Edited by Skylarr, 17 March 2015 - 11:05 AM.

[Bloodweaver]

Skylarr, on 17 March 2015 - 11:03 AM, said:

They've apparently made huge advances in heat management materials and efficiencies since the 20th/21st centuries, even though other technologies have remained relatively stagnant.

No kidding - considering that losing heat by radiation is an obscenely slow process!

Edited by Bloodweaver, 17 March 2015 - 11:09 AM.

[9erRed]

Greetings all,

Some additional info about Heat Sinks,

Heat Effects

BattleMechs are sealed and insulated vehicles, allowing them to fight under nearly any conditions. This prevents heat from venting off and 'Mechs have a lot of heat to shunt from the continuous megawatts of power they consume, not to mention heat from weapons fire and the environment. Excessive heat can impair or even damage a BattleMech's computers, electronics, and myomers, causing the 'Mech to move sluggishly and also to be inaccurate with its weapons.
High Heat levels can be dangerous to the safety of the MechWarrior, causing heat stroke. Excess heat can also cause any stored explosive ammunition to cook off explosively - usually a catastrophic event for the 'Mech and it's MechWarrior.

Heat Sinks

There is quite a bit of confusion about what BattleMech heat sinks really are. "Heat sink" is actually the wrong name. 'Mech "heat sinks" are actually heat pumps. However, the rest of this article will continue to use the term "heat sinks" instead of "heat pumps."

Heat sources

The fusion engine generates heat waste heat, in spite of converting most of the heat into energy. The balancing act of keeping a fusion reaction going often results in more fusion reactions being produced than needed for current energy demands. These extra reactions create waste heat, since they aren't converted into electricity. Energy weapons are inefficient at converting electricity into laser or particle beams, ballistic weapons create heat in their bores and barrels, and jump jets create a lot of waste heat. Lastly, myomers generate a large volume of comparatively lower temperature waste heat. Incidentally, myomers impose one of the primary limitations on the temperature a BattleMech can operate at, because as the myomers heat up, they become more resistive, less efficient, and less predictable at the same time. The acti-strandular materials in Myomers do not respond well to high temperatures. If Myomers become too hot, they will actually cook themselves, which results in the black smoke seen rising from extremely overheated battlemechs in combat.

Collecting Heat

The engine and weapons have cooling jackets hooked to tubes which are networked into their frames. These tubes connect to the heat sink network. Myomer bundles have coolant lines laced through them in a manner not unlike a vascular system. All of these coolant lines run into collection systems that connect to the heat pumps and radiators that dump the heat.
Coolant fluids differ between depending on the manufacturer of the heat sink. Oils, chlorofluorocarbons, water-based solutions, liquid nitrogen, gaseous nitrogen, gaseous helium and other formulations are used. There are no 'Mechs using molten metals like the Tharkad City fusion engine - that would simply be too hazardous in combat. This coolant solution is then circulated through the 'Mech by a wide variety of pumps. Most modern heat sinks no longer use mechanical pumps. Instead they use myomer wrapped flexible tubing that pulses (peristaltic) in order to circulate coolants. This setup is more tolerant of damage than centrally located mechanical pumps. In addition, the whole system of coolant lines employs many computer-controlled cut off valves to stop catastrophic loss of coolant due to damage, and computer controls can also reroute coolant around damaged systems.

Heat Pumps

Heat pumps collect and condense heat until it can be easily shunted out through the radiators, even into environments hotter than the 'Mech. Many different heat pumps are used by different manufacturers. There are vapor-compression systems, sonic cooling systems, magneto-caloric systems, expansion compression systems, heat expansion systems, and others.

Dumping Heat

At one end of the heat sink assembly is the radiator. BattleMech radiators aren't very different from car or refrigerator radiators. Radiators consist of finned tubing carrying hot coolant that is either air or water cooled. They are usually made of graphite which is five times more thermally conductive than copper. These radiators are always hidden under armored grills. Some Periphery nations have used copper for heat sink radiators which actually works fairly well because copper allows for thinner construction, meaning more surface area to radiate heat from. The net performance drop from using copper radiators is fairly negligible.
The wonder plastics of the first Star League had a big hand in enhancing radiators. While these semi-crystalline polymers don't quite have graphite's thermal conductivity, they are dramatically lighter, allowing larger radiators for the same mass as standard heat sinks. This what allows for "double strength" heat sinks. Unlike most recovered lostech in the Inner Sphere these double strength heat sinks did not originate from the helm memory core. The New Avalon Institute of Science was experimenting with this tech before the helm core was found. The Clans never lost this technology and they even improved it by making the material more crystalline, which makes for a more thermally conductive and compact but more brittle radiator. The required reinforcements keep the Clan double strength heat sinks at about the same mass as Inner Sphere versions.
Radiators are why "heat sinks" actually have to use heat pumps. The laws of thermodynamics state that heat flows from hot to cold. Thus, if your 'Mech is operating in a very hot environment, the radiators would actually send heat into your 'Mechs coolant system.

Just some info,
9erRed

Edited by 9erRed, 17 March 2015 - 05:58 PM.

[Twilight Fenrir]

Now that had some neat informatio, 9erRed, thank you!

I've never heard of the idea of myomer pumps, but that makes a good deal of sense... Very neat!

[Chiasson Brinker]

Page 38 and 39 of the Tech Manual have a good write up on engines and heat sinks along with a couple of neat cutaways.