Ice Refuelling

[Blue Ghost]

Str * 14 = lots of ice.

I'm guessing we're using a strength augmented vacc suit or hostile environmental suit. If they're wearing battledress, then it's a no brainer; cut, haul up and stuff in the hull.

 

[Blue Ghost]

Or, just grab yourself a sump pump;

http://www.sumppumpsdirect.com/Basement-Watchdog-BW1050-Sump-Pump/p2476.html

That one's rated at 4000 gallons per hour. = 15.1416471 m^3 = 15141.6 = 125.965583174 ~ 126 tons

*EDIT*
15.1416471 m^3 = 5.34722221 tons ~ 5.35 => 40ton tank / 5.35 gph = 7.5 hours
*END EDIT*

So, alternatively, punch through the ice, form a seal around the hose, and drill down until you hit liquid and let the pump do its thing.

Or, hand crank what you need;
http://www.globalindustrial.com/p/m...mpaignId=T9F&gclid=CNWvoe-norgCFRRk7Aod9REAQw

That pump is rated at 14 revolutions for one gallon. Ouch. That's one tired arm.

=> 14 rpg => 0.00378541178 m^3/rev

1 m^3 = 0.353146667 tons (call it dtons for argument sake...someone punch a hole in my math if I'm wrong)

=> 25 tons of fuel requires 18701 revolutions of hand cranking a pump.

That's a lot of work.

 

[atpollard]

Let me give it a try:

Let's Start with a goal of 1 dTon of LH2.
1 dT of LH2 = 13.5 cu.m. = 1 tonne (metric ton) of LH2.
Since Water is 2/18 Hydrogen (by weight), 1 tonne LH2 = 9 tonnes water/ice.
Since 1 cu.m. of water/ice = 1 tonne, 9 tonnes of water/ice = 9 cu.m water ice.
So: 1 dT LH2 = 1 tonne LH2 = 9 tonnes water/ice = 9 cu.m water ice.


A typical wheelbarrow holds 5 cu.ft = 1/7 cu.m. and requires about 5 minutes per load,
so the 9 cu.m of water/ice will require 63 wheelbarrow loads (9 x 7 = 63)
and 315 minutes (63 x 5 = 315).
315 min = 5.25 hours.
So harvesting LH2 from water/ice using a wheelbarrow will require 5.25 hours per dTon of fuel.

Filling the 40 dTon tanks will require 40 x 5.25 = 210 hours.


As a side point:
the 40 dtons of LH2 will equal 40 metric tons of LH2 ...
... which will be contained in 360 metric tonnes of ice
... which will be contained in 360 cubic meters of ice
... which will be contained in about 27 dTons of water/ice (360/13.5=26.7)
... which will fill the tanks about 2/3 full with water/ice (26.7/40=.667=2/3).


NOTE: The figures will be slightly different if one assumes 1 dT = 14 cu.m rather than 13.5 cu.m, but not by much. Also, the difference in density between liquid water and ice has been ignored since it varies with temperature and is very small at the extreme cold of places like Europa.

 

[atpollard]

Str * 14 = lots of ice.

I'm guessing we're using a strength augmented vacc suit or hostile environmental suit. If they're wearing battledress, then it's a no brainer; cut, haul up and stuff in the hull.

Please correct me if I am misunderstanding this, but Str*14 = about 100 kg (7*14=98; 8x14=112).

So if we compare carrying a 100 kg block of ice with pushing a 143* kg wheelbarrow load of ice, and assume both trips take 5 minutes per load, then:

Pushing the wheelbarrow will transport 9 tonnes of ice to make 1 dTon of fuel in 5.25 hours and carrying the block of ice will transport 9 tonnes of ice to make 1 dTon of fuel in 7.5** hours.

NOTES:
* 1 cu.m of water/ice = 1000 kg.
A wheelbarrow holds 1/7 cu.m. = 1000/7 = 142.86 kg per wheelbarrow load.

** 5.25 hours x 143 / 100 = 7.51 hours

 

[atpollard]

Or, hand crank what you need;
That pump is rated at 14 revolutions for one gallon. Ouch. That's one tired arm.

Let's try the hand crank:

1 cubic meter = 264 gallons
264 gallons x 14 revolutions per gallon = 3696 rev per cu.m.
Since 1 dTon of fuel = 9 cu.m of water, pumping enough water to make 1 dTon of fuel will require 33,264 revolutions (3696 x 9) of the hand crank.

Assuming about 1 revolution per second, each dTon of fuel will require 33,264 seconds = 554 minutes = 9.24 hours ... you are going to really need to hustle to keep up with the wheelbarrow and ...

... I agree: "Holy aching arms, Batman!"
(it sucks to refuel starships at TL 1)


Fortunately, we have electricity, so let's try the 4000 GPH pump.

1 cubic meter = 264 gallons = 264 gallons / 4000 GPH = 0.066 hrs = 3.96 minutes (let's call it 4 minutes).
Since 1 dTon of fuel = 9 cu.m of water, pumping enough water to make 1 dTon of fuel will require (4 x 9) 36 minutes with the electric pump.

So returning to the 40 dTon fuel tanks on our Scout ship, pumping water would only take 36 x 40 = 1440 minutes = 24 hours to refuel with a 4000 GPH electric pump.

 

[aramis]

Str * 14 = lots of ice.

I'm guessing we're using a strength augmented vacc suit or hostile environmental suit. If they're wearing battledress, then it's a no brainer; cut, haul up and stuff in the hull.

Nope. You're forgetting that you can lift and throw much more in low G environments. Can't accelerate it much faster, but can accelerate it. Two guys can move a 1 ton block of ice on Luna with just hooks and standard vacc suits. Each guy can throw 40kg the same distance they could throw a 7 KG block on earth.

Remember, a 1-handed drive sent the golf ball well over half a mile...

 

[HG_B]

Remember, a 1-handed drive sent the golf ball well over half a mile...

Imagine how large the golf courses will be on the Moon!

 

[atpollard]

Nope. You're forgetting that you can lift and throw much more in low G environments. Can't accelerate it much faster, but can accelerate it. Two guys can move a 1 ton block of ice on Luna with just hooks and standard vacc suits. Each guy can throw 40kg the same distance they could throw a 7 KG block on earth.

Remember, a 1-handed drive sent the golf ball well over half a mile...

So if I am following the implications of this successfully:
at 1/6 Earth gravity, a character can carry 6 times as much mass (since it will weigh less, but the force that his muscles deliver will be unchanged).

If so then we can revise this:

So if we compare carrying a 100 kg block of ice with pushing a 143* kg wheelbarrow load of ice, and assume both trips take 5 minutes per load, then:

To ...
A character able to carry 100 kg on Earth will be able to carry 600 kg at 1/6 Earth gravity (like on the moon) ...

Pushing the wheelbarrow will transport 9 tonnes of ice to make 1 dTon of fuel in 5.25 hours and carrying the block of ice will transport 9 tonnes of ice to make 1 dTon of fuel in 1.25** hours.

NOTES:
** 5.25 hours x 143 / 600 = 1.25 hours

 

[McPerth]

Pushing the wheelbarrow will transport 9 tonnes of ice to make 1 dTon of fuel in 5.25 hours and carrying the block of ice will transport 9 tonnes of ice to make 1 dTon of fuel in 1.25** hours.

NOTES:
** 5.25 hours x 143 / 600 = 1.25 hours

I'm not sure the weelbarrow will have the capacity to accomodate 9 m³ and keep the equilibrium to keep going. We must remember volumen also affects transport, not only weight.

Aside from all that, remember too this wáter must be then melt and electrlozyled, and oxigen separated to it and dumped to space (or, at least a part, used to renew own reserves). I guess most of this would also be done from the fuel tanks (I asume them comparimentalized), sending the wáter to the purification planet (that I asume has electrolyzing capability if the ship is able to refule from oceans).

Aside from all this taking also its time, we can asume some hydtogen is lost in the process and the last compartment of the fuel tanks can be left empty, as it holds water until the end of the process (each comparment holds the wáter to fill the next one, until the last).

 

[Carlobrand]

Training wheels on the wheelbarrow?

Occurs to me that transporting all this ice is like towing weight through water on a float - which is to say you still have to deal with the momentum you've imparted in the mass just by pushing it. You stop, 600 kg of ice disagrees with your decision.

 

[Blue Ghost]

Nope. You're forgetting that you can lift and throw much more in low G environments. Can't accelerate it much faster, but can accelerate it. Two guys can move a 1 ton block of ice on Luna with just hooks and standard vacc suits. Each guy can throw 40kg the same distance they could throw a 7 KG block on earth.

Remember, a 1-handed drive sent the golf ball well over half a mile...

True, but when I think of vacc suits, I think of Apollo mission spacesuits, and not the Mercury astronaut stuff or the even cooler 2001 type. It seems like it's a fairly clumsy proposition either way. I wonder how that would effect some guy trying to refuel his ship after being stranded on Europa.

 

[HG_B]

True, but when I think of vacc suits, I think of Apollo mission spacesuits,

I don't think your TL 6 craft has a Jump drive.

 

[Blue Ghost]

I'm not sure the weelbarrow will have the capacity to accomodate 9 m³ and keep the equilibrium to keep going. We must remember volumen also affects transport, not only weight.

Aside from all that, remember too this wáter must be then melt and electrlozyled, and oxigen separated to it and dumped to space (or, at least a part, used to renew own reserves). I guess most of this would also be done from the fuel tanks (I asume them comparimentalized), sending the wáter to the purification planet (that I asume has electrolyzing capability if the ship is able to refule from oceans).

Aside from all this taking also its time, we can asume some hydtogen is lost in the process and the last compartment of the fuel tanks can be left empty, as it holds water until the end of the process (each comparment holds the wáter to fill the next one, until the last).

Well, one cubic meter is the size of a VERY large moving box. It's more like the box a large cathode ray tube TV might come in. I personally can't imagine anyway, even in a low G environment that anyone could effectively move 9 of those at one time across a snow like or ice like surface, up a ramp, and then pushed into a fuel tank. That's just my gut feeling on it.

Imagine 9 TVs or TV boxes stacked on top of one another. A 9 meter tall stack of snow is, well, unwieldly in my opinion.

*EDIT*
Especially in a big clumsy vacc suit, on rough terrain, in a vacuum. in a low G environment. Just me

 

[Carlobrand]

...Two guys can move a 1 ton block of ice on Luna with just hooks and standard vacc suits. ...

Oooh, evil thought: it would be a rather nasty bit of business if you tried to stop that ton block by putting yourself between it and the hull of your ship. :devil:

 

[Blue Ghost]

Oooh, evil thought: it would be a rather nasty bit of business if you tried to stop that ton block by putting yourself between it and the hull of your ship. :devil:

lol, why would you do that?

 

[SpaceBadger]

Oooh, evil thought: it would be a rather nasty bit of business if you tried to stop that ton block by putting yourself between it and the hull of your ship. :devil:

Heh. Like those motion problems from Intro Physics, with the astronaut doing EVA w a gas gun, trying to stop a space rock before it hit his ship? Of course he had to position himself directly between rock and ship; too bad the acceleration of his gas gun was only enough to make the rock stop exactly touching the side of the ship. Goodbye, astronaut, hello, vacc-suit full of strawberry jam. :toast:

 

[aramis]

True, but when I think of vacc suits, I think of Apollo mission spacesuits, and not the Mercury astronaut stuff or the even cooler 2001 type. It seems like it's a fairly clumsy proposition either way. I wonder how that would effect some guy trying to refuel his ship after being stranded on Europa.

The rules provide for the NASA Mars Suit equivalent... and have done so since 1981 or before. (I don't have a 1977 set, neither in PDF nor dead tree, to check the mass in...)

 

[aramis]

Oooh, evil thought: it would be a rather nasty bit of business if you tried to stop that ton block by putting yourself between it and the hull of your ship. :devil:

Quite true, that, but you CAN just let it crash into the hold, since the velocity will be low enough to not do damage to anything metal.

 

[Blue Ghost]

How thick is a ship's hull anyway? From Snapshot it's a thousand points from explosive/energy weapons to form a breach in a bulkhead, so I think you're safe from a stack of ice or a pile of snow that's out of control crashing into the hull.

On suits; here's a hard science take on suits as traditionally found in NASA;

Me, I normally think of something a little more sleek and ergonomic when it comes to science fiction, but for traveller, because of previous artwork published and an emphasis on "hard science" (i,e, more "realistic" takes on science and technology), I tend to think of something a little more sleek.

Either way you've got a couple of layers of synthetic fiber with hoses and wires woven into the thing circulating air or water. And you're either carrying compressed air or are carrying some kind of gill that recycles it, which may not be that much extra weight, but it's weight you're not used to having on your body, including whatever bulk of the suit you're carrying.

It would interesting to see this experiment carried out.

 

[Carlobrand]

Quite true, that, but you CAN just let it crash into the hold, since the velocity will be low enough to not do damage to anything metal.

True, but ... the difference between Traveller and the real-life space program is that in Traveller, the folk doing this aren't elite astronauts hand-picked from a set of highly trained and educated volunteers. They're the same kind of Everyman who have these sorts of thoughtless-moment industrial accidents in real life, the kind who see someone pass out at the bottom of a large tank and rush to the rescue without checking to see whether the tank's air is safe. In the Traveller universe especially, with the possibility for gravity and even gravitational direction to be altered by setting a switch, there's a great potential for one's "instinctive" reactions to be completely wrong.