Questions tagged [liquid-fuel]
Questions regarding rocket propellant in liquid form, the main type used for chemical rockets.
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Fuel above oxidizer or oxidizer above fuel? [duplicate]
If you look at several mainstream rocket designs (i.e. Shuttle, Falcon, SLS, and even the first stage of the Saturn V) within each stage the liquid oxygen tank (blue) is placed above the liquid ...
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What purity of LOX is required for use in rocket engines?
Can any one suggest, is it necessary to check purity of LOX before it is used in an engine? What are the impurities which can affect its performance? What types of tests can we perform to check its ...
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Technical Question on Ignition Back Pressure
I am looking for understanding the backpressure or pressure stabilization of the injector inlet of the engines, during ignition (T-0). Are there books or papers that you suggest to check for ...
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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 ...
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What is the maximum number of times a liquid rocket engine has detonated/ exploded during development?
My question comes from a lot of research and curiosity. Do they stop the development process at 10-20 detonations/ explosions? Or do they keep continuining solving one problem after the other. Modern ...
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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 ...
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Why do methane engines require burn-off igniters?
When I was watching the flight readiness test firing of the Vulcan’s BE-4 engines, I noticed that there were igniters similar to the ROFI igniters seen on liquid hydrogen rockets. Why do methane ...
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Rough values for the staytime or characteristic length of the combustion chamber of an oxygen/methanol rocket engine?
I'd like to have some idea of the staytime or characteristic length of the combustion chamber of an oxygen/methanol rocket engine.
Are there sources for this, or a way to estimate it?
I've tried, but ...
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Has a rocket engine with LOX as the oxidizer ever fired beyond the GEO belt?
Intuitive Machines' Nova-C lunar lander is scheduled to launch in mid-February of this year. Notably, the lander uses liquid methane as fuel and liquid oxygen as the oxidizer, and it will rely on this ...
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Multi-stage combustion products?
Okay so I've never seen anything about this before, and that's probably for a very obvious, very simple reason I am far too dim to think of, but here goes:
Most combustion reactions in rocket chambers ...
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Can Solid Rockets (Aluminum-Ice) have an advantage when designing light space-tug for LEO?
This is a new subject for Space Industry – heavy spacecraft (1200-ton) in LEO that have to burn hundreds of tons of propellant to get going to their destination.
It looks inefficient to launch 7+ fuel ...
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What does "pogo bleed" entail?
At around T-3:00 on every Falcon 9 countdown, we hear the following:
Stage 1 pogo bleed verification
I assume they are referring to pogo oscillation, but what exactly does "pogo bleed" ...
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Does "% Throttle" refer to fuel flow or thrust?
the question Is it possible to throttle down the thrust in a rocket engine to 1% just like in KSP? discusses the ability of liquid fuel rockets to throttle. By convention, does the “% throttle level” ...
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Has combustion chamber water injection been used in RP1 rocket engine design?
Goddard’s rocket, the V2 rocket and Redstone all used water in their Alcohol fuel for combustion temperature control. To the best of my knowledge, water has not been used in RP1 fueled rockets for ...
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Rocket maximum distance [closed]
let's say I have a liquid rocket
what would maximize the distance traveled by the rocket thus consume less fuel
constant velocity or acceleration or why?
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Dependance of slosh mode on ratio of liquid height to tank height
If two liquid tanks of the same cross-section but different heights have the same liquid up to the same depth, will sloshing be the same or different in both tanks?
I would assume they would be the ...
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Propellant Density Calculation for LOX/Kero
I am trying to make sense of the equation for propellant density calculation, rho=(rw-1)/(rw/bo+1/bf).
Sutton, 7th edition, gives this equation (7-2) as:
$ \ \ \ \rho_{av} = \frac {\rho_o\rho_f(1+r)} {...
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What is the exhaust temperature of a liquid oxygen + liquid hydrogen vacuum engine?
Ideally the exhaust of stochiometric liquid oxygen + liquid hydrogen rocket would be fast moving chunks of ice at zero kelvin. In this way all the potential chemical energy in the fuel/oxidizer is ...
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Why did the space shuttle tank look the way it did? [closed]
Why did the space shuttle's external fuel tank look the way it did? Why that design? While we're on the subject, what's the history behind this design, was it planned to be that way, or were there ...
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Is adiabatic flame temperature the same as nozzle stagnation temperature?
I am trying to understand whether these two concepts are in fact, the same parameter.
The way I see it, the adiabatic flame temperature is the highest temperature achieved by stoichiometric combustion ...
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What are the advantages and disadvantages of using either liquid hydrogen or liquid methane based rocket fuels?
I am working on a near-hard scifi story that mainly involves travel across a single widely populated solar system. I imagine that realistically there will probably be a wide variety of ship designs, ...
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What is the purpose of the shrouds surrounding these rocket engines?
While researching the purpose of some rocket engine components, I came across several images of perforated shrouds surrounding the combustion chambers of rocket engines.
I was highly curious about ...
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Relative location of RP1 and LOX tanks in Saturn V [duplicate]
In Saturn V, the 2nd and 3rd stages had their fuel tank located above the LOX tank, but in the first stage, the LOX tank was located above the fuel tank. Is it because the individual stages had their ...
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Is N2O a practical monopropellant?
N2O has been worked with very early on in the 40s and now again is seeing a resurgence. Is this interest merited, disregarding its apparent non-toxicity, and how well does it perform in an engine/...
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Is it more expensive to send a chemical rocket from surface of Earth to an orbit or from this orbit to Mars?
I was trying to understand how cost-effective it would be to use an ion engine to power a mission. But since these propulsion systems cannot be used to leave Earth's gravitational field due to their ...
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Starship: Methane and Oxygen can't both be liquid, except in a narrow temperature range. Is this a problem for interplanetary voyages?
On an extended spaceflight in Starship, the liquid propellant and oxidizer will tend towards the same temperature. The tanks can be refrigerated by boiling off contents, but your mileage may vary ...
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Is Lucy fueled with hydrazine and liquid oxygen?
On Sept. 18, propulsion engineers finished filling Lucy’s fuel tanks
with approximately 1,600 pounds (725 kilograms) of liquid hydrazine
and liquid oxygen, which make up 40% of the mass of the ...
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Can the cryogenic expansion of liquid oxygen and liquid hydrogen be used to pump a rocket engine?
A common fuel amongst rockets is that of the combination of cryogenic liquid hydrogen and liquid oxygen. I looked at the design of a simple rocket using this cocktail that is the propellant and found ...
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Does anyone know the stay time, or what characteristic length should be used, for a LOX/LCH4-fuelled rocket engine?
Just what it says on the tin. I need to know either the "stay time" (Ts) or characteristic length (L*) that would be used to figure combustion chamber dimensions used with a LOX/LCH4-...
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Why can solid rockets be both the skinniest and most spherical launch vehicles while liquid fuel rockets have a more limited range of aspect ratios?
Question: Why can solid rockets be both the skinniest and most spherical launch vehicles while liquid fuel rockets have a more limited range of aspect ratios? Are there fundamental engineering ...
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Comparison of rocket engines using LH2 & LOX as propellants
I am a bit confused - If it is correct that RL 10 and LR 87-LH2 both were developed in 1950 by Aerojet, and both used LOX and LH2 as the propellants, if so, then why was there a huge difference in ...
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What expansion ratio is the best for mars surface level engines?
What expansion ratio is the best for mars surface level engines?
For launches from Earth, first stage nozzles are much shorter than second stage nozzles because of Earth's high sea-level pressure. For ...
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Can rocket engines which use hypergolic propellants be augmented with LOX for increased efficiency?
Hypergolic rocket engines typically use NTO and hydrazine based propellants.
Wikipedia page on Liquid Rocket Propellants shows N2O4 and N2H4 at 1.36 ratio to have 286s Isp at sea level.
My question is ...
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Was liquid ozone + fluorine ever tested as an oxidizer? Ever with jet fuel?
Searching for ozone layer circa 1957 I got Theoretical Rocket Performance of JP-4 Fuel with Mixtures of Liquid Ozone and Fluorine, NACA RM E56K14, Issue 58, Volume 63, Vearl N. Huff, Sanford Gordon. ...
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Can kerolox or SRB soot particles grow too large too quickly; not accelerated in expanding exhaust leading to a loss of mass-specific impulse?
In this answer to Is methyl silane CH6Si ever considered as fuel in rocketry? I argue that there's no huge loss in mass-specific impulse (Isp) when producing sand (and by extension soot) in the ...
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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 ...
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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 ...
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Injector design - LOX vs nitrous oxide
What will be the main design differences between using liquid oxygen and liquid nitrous oxide as oxidizer in a bi-propellant rocket engine? What liquid/gas properties (vapor pressure etc.) play the ...
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Open source liquid rocket engine
Is there an open source bi-propelant liquid rocket engine that would have all the documentation, computations, test results and 3D design files (CAD) freely accessible?
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Highest Isp achieved with nitrous oxide as oxidizer
What is the highest Isp achieved on orbital rocket for an engine that used nitrous oxide as oxidizer? Both hybrid and liquid engines can be considered.
Not considering nitrous oxide monopropellant ...
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If high-test peroxide is most stable when pure, why are most uses of it in rocketry at lower concentrations?
Per the Wikipedia article for High-test peroxide:
Hydrogen peroxide becomes more stable with higher peroxide content. For example, 98% hydrogen peroxide is more stable than 70% hydrogen peroxide. ...
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Is there a "green" hypergolic propellant?
Is there any such thing as a non-cryogenic, liquid, "green" hypergolic bipropellant, where green means environment friendly and non-toxic?
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What is the products of a catalyzed reaction between Hydrogen Peroxide and Ethanolamine with Copper(II) Chloride?
I found this article about Hypergols, specifically H2O2. It mentions in table 3 and in the body of the paper that they found that Ethanolamine with Copper Chloride reacted vigorously. In my search for ...
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Liquid fueled suborbital rockets?
Which suborbital (sounding, balistic, amateur or else) rockets use or used liquid fuel?
I could find (with help from A. Rumlin)
New Shepard - Blue Origin - RP-1
Spica - Copenhagen Suborbitals - ...
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Rocket fuel cost to launch 1 kg to orbit
I have 2 questions about the cost of liquid rocket fuel to launch (anything) to LEO orbit. Let's assume we use fuels used in commercial spaceflight today (probably LOX+LH2 or LOX+RP-1 etc.).
What is ...
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Is there a distinct flame-front in a liquid-fuelled rocket combustion chamber?
Liquid fuel and liquid oxidizer are injected at high pressure through small orifices into the 'top' of a rocket's combustion chamber. The intention is that these mix quickly and then burn completely ...
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How many times is a single rocket engine tested?
When a rocket engine is loaded into a test stand is it tested once before removal or is it allowed to cool and then tested again. Is every liquid-fueled rocket motor that flies to space first tested ...
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Can liquid rocket engines have the same thrust as solid rocket engines?
Take the Vega rocket launcher for example. Its first three stages are solid rocket engines and burn at a relatively short time. If I were to change its first stage into a liquid rocket engine, can ...
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What is the effect of calorific value of fuel on the specific impulse of a rocket engine?
What is the effect of calorific value of a fuel on the specific impulse of a rocket engine? Other things remaining the same, and if it is possible to use both, will the same fuel provide the same ...
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Dinitrogen tetroxide decomposes to nitrogen dioxide at room temperature, but rockets that use it are usually said to use N₂O₄ and not NO₂ - why?
To the best of my understanding, both dinitrogen tetroxide and nitrogen dioxide are usable and perform quite similarly as oxidizers, but rockets that use either are almost always said to use ...
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