All Questions
15
questions
4
votes
1
answer
112
views
What is the dark brown gas emission seen during the ascent of Starship?
During the video (see below) of Starship IFT-4 there is a lot of brown smoke or gas in the Superheavy exhaust from near the start for almost 30 seconds. Is this NO2? If so roughly how much is produced?...
- 9,772
1
vote
0
answers
83
views
What is the ratio of air and ethyl alcohol that must be in order to power a rocket engine? [closed]
There is a rocket engine that will run on a fuel pair: air + ethyl alcohol, but what percentage of components should be supplied ...
11
votes
2
answers
4k
views
Why are nitric acid and hydrogen combinations not used as rocket fuel?
I was recently doing a chemistry assignment about bond energy when I noticed the incredibly low bond energy of nitric acid. Given the high bond energy of a nitrogen triple-bond, this set me wondering ...
8
votes
1
answer
638
views
Silane as a rocket fuel
At about 6:55 into the video Why Moon Mining Will DEFINITELY Be A Thing it is stated that lunar silica (SiO2) could be turned into silane (SiH4), which is the silicon analogue of methane. It also ...
- 13.1k
2
votes
1
answer
179
views
Why maintain nominal engine inlet mixture ratio for a gas generator engine?
I was reading up on gas generator cycles and came across the following paragraph talking about fuel or oxidizer rich gas generators and the different mixture ratios for the main combustion chamber ...
- 1,154
1
vote
0
answers
436
views
Can Chemical Engineer work on something related to space?
I am an undergraduate student (scientific section) living in Qatar. I have a big interest in astronomy and astrophysics and have participated in the IOAA (International Olympiad on Astronomy and ...
- 11
3
votes
1
answer
511
views
What would be the performances of chlorine trifluoride as an oxydizer?
Inspired by this comment
Assume that a particularly deranged moustache-twirling villain with way more time and resources than is reasonable decides to build a satellite-launching rocket using ...
- 779
6
votes
1
answer
1k
views
Density of propylene when used as rocket fuel, and advantages (if any) over RP-1?
Recently Vector space from USA has said that propylene is a better choice of fuel than RP-1. See Ars Technica's After a decade of testing, propylene rocket fuel may be ready for prime time
Why is ...
- 69
6
votes
1
answer
12k
views
Can I make my own RP1? [closed]
Is it possible for me to buy kerosene from a local store and then try to refine it to the extent where it would be considered RP1. If so how would I do it? For those who are wondering me and a group ...
- 167
2
votes
1
answer
351
views
What proportion of a rockets fuel remains unburnt?
Presumably liquid rocket combustion is never 100% efficient, so what proportion of fuel does typically remain unburnt, venting into the atmosphere, and does this vary for different rocket designs and ...
9
votes
4
answers
6k
views
Is there a maximum Isp for "exothermic chemical reaction rockets"?
The question Is there a maximum $\text{I}_{sp}$? reminded me that I once read somewhere that the maximum possible $\text{I}_{sp}$ for a rocket engine based on expansion driven by exothermic, ...
- 148k
12
votes
5
answers
2k
views
What limits burning speed of solid propellant?
SRBs and missiles use grain to regulate thrust over time, as only exposed surface of the propellant burns.
But what causes propellant to burn only on the surface, and regulates the speed at which the ...
- 55.1k
5
votes
5
answers
785
views
What would adding 15% nitrogen do to pure oxygen as an oxidizer?
I'm working through Sutton's "Rocket Propulsion Elements," (8th Ed.) and it is mostly gibberish. However, I understand a little bit. Anyways, the question is: When using RP-1 as a fuel, your oxidizer ...
- 208
10
votes
2
answers
2k
views
What is required to produce rocket quality methane fuel and oxygen from Mars' atmosphere?
Turning $\require{mhchem}\ce{CO2}$ and some hydrogen into $\ce{O2}$ and $\ce{CH4}$ seems pretty straightforward and has been known since early chemistry in the 19th century. But what about the quality,...
- 27k
6
votes
2
answers
6k
views
What does "self-pressurizing" mean in regards to propellant tanks?
I've come across this term a few times. IIRC, liquid hydrogen is "self-pressurizing", but other fuels are not. Apparently, if a propellant is self-pressurizing, we do not need to build any complex ...
- 4,596