Heating COHAB anomaly - discussion

[Marco2001]

Mars is cold. At equator at highest it gets to +20 deg.. On coldsotrms at polar regions it can drop to -120 deg.
With that said - we need to properly suply our base with heat-shields, heater coils, nuclear reactors and radioisotopic links that will heat the base more right?
WRONG!
It has been a shock to me to but, as I looked closerly to the specification plans of martian habitats, they not only do not include any heating mechanism...they include COOLING machines for COHAB?
At first I though - WHAT THE HELL? It's +15 deg inside COHAB and -60 normaly outside the base, and you don't loose heat?!
As I looked closerly I understood why. It's quite easy reely.
The thing is - martian air is so thin that thermodinamicaly it's more considered as a vacume...which is one of the best thermic isolators.
The incoming winds as cold as they are, cannot lower the habitat's temperature becouse they have no heat-mass.
Morover - even without a heat shield, the habitat is basicly an isolated metal box...more like a thermos.
Considering that of above - you would not only need to heat the habitat, but without cooling it would eventually heat up to ~37 deg of a humans normal heat.
But that's not over - COHAB has lots of machines, and they produce heat. Many of them needs Super-Heat for catalitic reactions. Without cooling the COHAB, the temp could eventually go as high as 90 deg...
Preety surprising huh?

So...knowing that...doesn't the heaters needs to be a little more...useless or something? (Doesn't it change anything?)

[profit004]

Wouldn't that also negate the need for heating in the space suits and instead mean they need to cool like ones in space do?

Knew the martian atmosphere was really low pressure but I never even thought about the fact it would have close to no heat capacity.

[Snowpig]

check out the wiki-entry for a  space suit.

My (uneducated) guess is, that the EVA on the mars surface would need a bit less powerful cooling system than a suit designed for open space, since there will be a little more evaporation

[Hyper]

Well as it turns out the R value for mars would come in about 200 so Marco found some interesting facts. The building is not a metal can it is expanded foam with a double layer of micro carbon fiber in and out for blocking radiation. The construction panels are light weight, easy to construct on Mars and when locked together form a air tight seal with enough strength to hold 12 to 14 psi. I will look more into the thermal issue and will probably change the way the heater works to a thermal conditioner. Game wise this creates some bad issues for me but it's what I do. I dont think we will have the heat problem you see as the cubic volume and surface area especially in the floor would conduct alot of heat out, opening doors etc will be a factor as well as pumping all the heat we can down the wells to melt the ice. Will do some more research.

[Marco2001]

I was thinking about this for some time and her's what I came up with:

The base needs to be both equiped with heaters aswell as radiators.
Heaters are used at the start of the game, during coldstorms, accidents and during unusual big heat drainage.
Radiators should be used later in the game, when your base has estabilished stable conditions (air mix, temperature and preasure).

At start the base is exposed to martian air. The base has the air's composition, heat and preasure as on Mars. Every equipement must have the same temperature as outside the base. When you seal the hatch, the base will still have that temperature, and calculating the total mass and volume, it would take weeks to fully heat the base with human+machine excess heat only. Therefore - we heat it up with a heater coil to stable conditions. When those conditions are archieved, the heaters are turned to "STANDBY MODE" or "OFF" since the temperature will rise without them. Now the problem is that the heat will slowly but continually raise. COHAB activates passive and active radiators. If not instaled or breaked, the temp will rise and rise and rise, untill it will be to hot.

Some heat is lost during normal activities like Hyper said. Some lost in the airlock, and the other part can be lost in the air-circulation process (air recuperator prevents that).

IDEA: Each equipement while activated drains power and returns some heat like a heater coil.
The same with humans. When more astronauts they are, the faster will the module get heat from them. 
 

[profit004]

I think quite a bit of heat will be lost to geo-sinked conductivity unless the base is insulated on the bottom.

I would have to guess it would be relatively easy to balance how much heat goes into the ground with a simple thermal transfer loop under the floor next to the cold ground *maybe just an air duct would be all that is needed.

[thedubman]

@profit- I would have to agree, it would seem much easier to control heat (loss) than it is to control the cold.

[jkcjaneway]

you also have to take in the account that mars has little to no magnetic sphere so all forms of radiation and space debries rain down on the red planet. And this isn't green goo radiation or radiation sickness its more or less getting a radiation burn from UV so it kinda doesn't make sense to get a radiation warning in a closed eviorment unless there are windows or other see-through surfaces. IT kinda just doesn't make sense to die of radiation while inside the base and in an eva suite.

[profit004]

you also have to take in the account that mars has little to no magnetic sphere so all forms of radiation and space debries rain down on the red planet. And this isn't green goo radiation or radiation sickness its more or less getting a radiation burn from UV so it kinda doesn't make sense to get a radiation warning in a closed eviorment unless there are windows or other see-through surfaces. IT kinda just doesn't make sense to die of radiation while inside the base and in an eva suite.

Sadly from what I understand , you are wrong....

Galactic sourced cosmic radiation goes through the martian habitation constructions like they are not even there...  It takes something like a 20 feet of ground to effectively stop most of the damaging cosmic rays...

The kind of radiation that would be blocked would be things like radiation from a Coronal Mass Ejection, or a Solar Proton event.  Admittedly a lot of rads, but kinda rare. 

Anyhow... These are all Galactic Sourced cosmic rays causing radiation for now since it comes when the sun is up or down and sadly the little shelters will just not protect an astronaut from it...   

[Hyper]

Random unexplained deaths are code grimlins for now so dont dwell on that too much.

[Kilroy_Smith]

Should we bring along our stuffed gremlins and boomerangs for good luck?

[Kraniel]

Whatever you do ... don't get the mogwai wet...

[thedubman]

I could never understand the 'dont feed the mogwai after midnight' bit - how long after midnight? 1 min past? midday?

[profit004]

I could never understand the 'dont feed the mogwai after midnight' bit - how long after midnight? 1 min past? midday?

It is actually determined by a psychosomatic reaction inside the mogwai's mind, if they believe they were fed after midnight, no matter what time it actually is, they will convert to gremlins.     =p

[thedubman]

That must mean mogwai's have sense of time and henceforth 'self awareness' they know of there existence at a point in time- even thougth time is nothing more than an abstract concept.