All Questions
Tagged with cryogenics liquid-fuel
13
questions
6
votes
2
answers
1k
views
What's the difference between cryogenic and Liquid propellant?
According to my understanding (which may be incorrect), the cryogenic form and liquid form of propellant both use a fluid as an oxidizer and fuel. Research tells me crygenic propellant is more ...
- 527
12
votes
1
answer
3k
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Why is an inflatable balloon inside a fuel tank not used to prevent fuel from "sloshing around"?
After seeing all the Starship failures, having something with a membrane keep things in place seems like an obvious solution. Has it been considered or tested - or do we simply lack a material that is ...
- 517
4
votes
1
answer
607
views
Why are propellant tanks filled from the bottom?
It seems that the norm is to (fast-) fill fuel and oxidiser tanks from the bottom. For example, on this drawing of the Saturn S-IC stage you can see the LOX and RP-1 fill valves at the bottom of the ...
- 14.5k
10
votes
2
answers
2k
views
Why can’t cryogenic propellants be storable, at least on the ground, via refrigeration?
Cryogenic fuels (liquid hydrogen, liquid methane)1 and oxidisers (liquid oxygen)2 are the rocket propellants of choice where raw performance is the overriding concern, due to the very high performance ...
- 4,157
2
votes
0
answers
92
views
LOX as annular heat sink
I'm thinking of my time spent working with cryostats. Liquid helium pot on the inside, and surrounded by a liquid nitrogen jacket. And the whole thing insulated with vacuum and superinsulation. (...
- 4,287
8
votes
1
answer
865
views
How will Robotic Refueling Mission-3's liquid methane tank remain full for six months without any boil off?
Space.com's Lasers, Crystals and 36,000 Worms Will Ride a SpaceX Dragon to Space Station says:
To fly on those journeys, astronauts might have to someday harvest fuel from the surface of the moon ...
- 149k
2
votes
2
answers
459
views
Why are LOx plumbing not insulated?(ref: Huzel and Huang)
In the book Modern Engineering for Design of Liquid Propellant Rocket Engines, the following excerpt appear in chapter 9 - Interconnecting Components and Mounts:
The liquid-oxygen lines were not ...
- 4,479
19
votes
3
answers
4k
views
How does SpaceX plan to deal with boiloff on the trip to Mars?
Both BFR (Big Falcon Rocket) booster and BFS (Big Falcon Spaceship) are to run on Raptor engines, fueled with liquid methane and liquid oxygen - cryofuels.
The trip to Mars will take at least a couple ...
- 55.1k
15
votes
1
answer
2k
views
What is the advantage of using Helium over Nitrogen when used for pressurising LOx?
In this Twitter post of the plumbing line diagram(left half) by LauncherSpace, one can notice that Helium is used for pressurising LOx while Nitrogen is used for pressurising Kerosene.
Why the ...
- 4,479
2
votes
1
answer
1k
views
ULA's plan for LH2/LOX 2nd stage that can maintain propellant for an extended period of time?
Business Insider's (long) article SpaceX's biggest rival has a 'genius' plan to cut its rocket launch costs more than 70% contains the statements sourced from ULA's CEO Tory Bruno:
Vulcan should ...
- 149k
12
votes
1
answer
3k
views
The principle behind regenerative cooling?
In regenerative cooling the fuel is passed around the nozzle before being pumped into the combustion chamber right? I don't really see how this affects cooling itself, since the heat captured around ...
- 741
4
votes
1
answer
631
views
Liquid Helium (4.2K) sealed, then raised to sub-LOX temperature (~70K) - what is the new pressure?
In this question there is discussion of the large differences in temperature between liquid helium-4, subcooled liquid oxygen (sub-LOX) and cold kerosene (RP-1). Approximate temperatures are 4.2K, ~...
- 149k
8
votes
4
answers
7k
views
Autogenous pressurization with sub-cooled propellant
In his IAC 2016 talk, Elon Musk said (at 28m 4s in the video) that the ITS booster tanks would use autogenous pressurization. This means there is gaseous oxygen resp. methane in the tank. To stay ...
- 2,179