Gas vs. liquid heat transfer loop efficiency

[TunderLock]

Hi guys,

Can anyone get me started on the math in comparing the two cases below:

 

1. Two gas pumps driving 1kg packets of hydrogen through a thermo regulator.

2. One liquid pump driving 10kg packets of liquid O2 through an aqua tuner.

 

Assume both rely on a Hydrogen/Wheez chamber to delete the moved heat. I feel like case 2 should be much more efficient because:

A. You only need 1 pump to drive 10kg packets. 

B. You're only paying 120 Watts per kg on the aqua tuner compared to 240 on the thermo regulator. 

I'm just wondering how much better off I am exactly after accounting for specific heat capacity (where hydrogen is better). Can anyone get me started on the precise math? The DTU change derped me. 

Once I've primed a LOX box with a hydrogen loop, I'm way better off using the LOX to cool new O2 than continue using the hydrogen right?

[Djoums]

1DTU = 1j basically, 10kDTU/s mean 10kW.

H2 has a heat capacity of 2.4, so the thermo regulator will displace 2.4 * 1000 * 14 = 33.6kW of heat.

Liquid O2 has a heat capacity of 1.01, so the aquatuner will displace 1.01 * 10000 * 14 = 141.4kW of heat.

The second case is indeed more efficient but note that you'll need 12 wheezeworts to compensate for that, each one removes 12kW of heat when sitting in H2.

[TunderLock]

2 hours ago, Djoums said:

1DTU = 1j basically, 10kDTU/s mean 10kW.

H2 has a heat capacity of 2.4, so the thermo regulator will displace 2.4 * 1000 * 14 = 33.6kW of heat.

Liquid O2 has a heat capacity of 1.01, so the aquatuner will displace 1.01 * 10000 * 14 = 141.4kW of heat.

The second case is indeed more efficient but note that you'll need 12 wheezeworts to compensate for that, each one removes 12kW of heat when sitting in H2.

Thanks for this

Continuing on for the cost/benefit analysis:

Case 1 will cost two gas pumps and a regulator worth of energy or 0.72kW to move the 33.6kW of heat.

Case 2 will cost one liquid pump and an aqua tuner of energy or 1.44kW to move 141kW of heat.

Per kW of energy, the gas approach moves 46.7kW of heat while a LOX loop moves 98.2kW.

A LOX loop is twice as energy efficient as a hydrogen loop at moving heat.

Please do challenge the math

(Note to others reading this without context, this is only relevant for extreme low temperatures. Oil/water loops would be cheaper again since you could do away with the aqua tuner.)

 

 

[Djoums]

25 minutes ago, TunderLock said:

Per kW of energy, the gas approach moves 46.7kW of heat while a LOX loop moves 139.6kW.

A LOX loop is three times more energy efficient than a hydrogen loop at moving heat.

Second case is 141.4/1.44 = 98.2kW of heat displaced per kW of electricity, about twice more energy efficient than H2 cooling.

[TunderLock]

Yep fat finger fail on my calculator Will edit for those who only read that far. 

[mathmanican]

If you have the gas loop around, then the air pumps are irrelevant. They are only used to initially fill the pipes. The hydrogen radiator, once started, doesn't need air pumps. You could easily have 5 thermo regulators, equally spaced in your loop, to keep the temp constantly low.  

• 5 Thermo Regulators  = 5*33.6kW = 168kW of cooling for 1.2kW power.
• 1 Aquatuner = 141.4kW of cooling for 1.2kW power. 

The hydrogen loop wins, hands down, if you are looking at power efficiency. You just need more space to spread out the heat loss (enters radiant pipes). 

The LOX machine loop with aquatuner is very space efficient. It is not more power efficient. 

[TunderLock]

On 18/09/2018 at 3:32 PM, Djoums said:

1DTU = 1j basically, 10kDTU/s mean 10kW.

H2 has a heat capacity of 2.4, so the thermo regulator will displace 2.4 * 1000 * 14 = 33.6kW of heat.

Liquid O2 has a heat capacity of 1.01, so the aquatuner will displace 1.01 * 10000 * 14 = 141.4kW of heat.

The second case is indeed more efficient but note that you'll need 12 wheezeworts to compensate for that, each one removes 12kW of heat when sitting in H2.

The new super coolant now blitzes everything previously:

Super is a liquid with a heat capacity of 8.44, so the aqua-tuner will displace 8.44 *10,000 * 14 = 1181.6kW of heat.

In infinite loops (without pumps) super coolant is now 7 time better than a hydrogen gas loop and 8.4 times better than LO2. It's a monstrous upgrade in cooling efficiency. 

Moreover, with a freeze point of -266C and a boiling point of 436, you have very little risk of breaking pipes whilst being able to go even colder thana hydrogen loop. Klei was not inaccurate with the title super coolant. 

[Segato]

On 10/5/2018 at 12:35 AM, TunderLock said:

The new super coolant now blitzes everything previously..

Which "super coolant" ?

[Christophlette]

10 minutes ago, Segato said:

Which "super coolant" ?

It is a new liquid added in the preview of the Space Industry Upgrade. I will come in a week and a half. But its stats may change before it is actually released.

[SakuraKoi]

I only have one question I'd like to ask about the super coolant:

Will it be rainbow-colored?