Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
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What kind of propulsion did/does the Raytheon EKV vehicle use?
Raytheon has developed an Exoatmospheric Kill Vehicle, designed to intercept an ICBM and destroy it through a collision. Here are some related links:
Wikipedia page
YouTube video about the project, ...
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Methane vs propane as rocket fuel [duplicate]
How would propane compare with methane as rocket fuel?
Propane can also be stored as liquid under pressure.
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Can hydrogen peroxide and propane be a good rocket propellant combination?
The decomposition of hydrogen peroxide can be used to spin the turbopump and then it can be mixed with propane in the combustion chamber
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Computing Flight Characteristics for Different Propellant Grain Geometries?
Consider the following image:
I am interested in mathematically accounting for some of these different geometries but have had little success so far in finding how this can be done. The first thought ...
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Do larger rockets tend to have a better mass ratio due to the square cube law?
Do larger rockets tend to have a better mass ratio due to the square cube law? I mean, larger tanks have a better surface-to-volume ratio, so their weight-to-volume should be improved
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Which are more efficient: oxidizer-rich or fuel rich rocket engines?
Several internet articles claim that the high Isp of the Soviet RD-180 engine (as used in the Atlas III and V launch vehicles) was (at least partially) due to the fact the RD-180 ran oxidizer-rich, ...
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Hydrogen-propelled space elevator [closed]
I'm working on a space elevator design using kerosene-burning jet engines and dirigibles supporting 1km stages of pipeline and cable stretching up to the end of the stratosphere (~50km), then using ...
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How does SpaceX prevent fuel from cluttering together in zero G [closed]
What is the solution to stop fuel inside starship collecting in center of the tank during zero G flight? Here is a rough sketch of starship with rudimentary diaphragm system to control flow of fuel ...
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Non-Cryogenic Propellant Transfer
I know there are programs like the Rocket Lab CryoSat, but I was wondering if there have been any tests of non-cryo propellant transfer?
I know the Space Station refuels with a storable hypergol, but ...
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Semi-Cryogenic HTP/LH2 engine?
Also see HTP as oxidizer for main propulsion
(for more info on history of H2O2/HTP in rocketry)
Note: HTP and H2O2 will be used interchangeably
I know the Black Arrow LV (The first orbital lipstick) ...
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How do you find the burn-time of a specific solid rocket fuel?
I read this post about finding the propellant mass needed to reach a specific altitude: How do you find the propellant mass needed to reach an inputted altitude?(altitude at end of burn plus altitude ...
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What is the A in the mass flow rate formula for solid rocket propellants? How do I get the chamber pressure? [closed]
I believe the mass flow rate formula for solid rocket motors is:$$\dot{m}=p_pA_br$$ What is $A_b$ in this case. Is it the cross-sectional area of the hole in the grain? What is there is a nozzle? What ...
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What would it take to collect methane from the atmosphere and use it as rocket fuel?
SpaceX is currently dealing with a lot of environmental regulation issues with Starship. One issue they have is the amount of CO2 Starship produces. Their falcon 9 produces 440 tons of CO2 each flight,...
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Debunking Apollo 11 based on the fuel usage [duplicate]
I have checked the NASA docs and it says they needed hundred thousand liters of liquid hydrogen for the various stages of the Apollo 11 mission. For example stage 2 was calculated to need at least ...
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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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Would reaching an elliptical orbit with the same mean altitude as that of a circular orbit require the same amount of fuel?
Would a rocket that wanted to reach an elliptical orbit with a perigee of 100 miles (160 km) and an apogee of 300 miles (480 km) burn the same amount of fuel as a rocket that wanted to attain a ...
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Going over the Apollo fuel numbers and I have many questions
I was reading through Apollo by the numbers and I noticed the LM descent to the moons surface consumed 17,414kg of fuel out of a total of 18,184kg leaving only 770kg of fuel.
But then in the very next ...
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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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Deep space mission propellant
For an interplanetary mission that has a duration of 40 years cam we use hydrogen peroxide monopropellants? Can we use arcjets?
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Propellant choices for a Mars landing; tradeoffs between LOX/CH4 and H2O2/RP-1?
What are the tradeoffs between LOX/methane and peroxide/kerosene for a Mars landing mission?
In which ways are each better or worse than the other?
I think the second one would more attractive for ...
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How to estimate the fuel required to send 1 kg to lower mars orbit?
Imagine a rocket with a payload of 1 kg. How much liquid fuel would be required to send that 1 kg payload to lower mars orbit. (1 kg is just the payload not the whole dry mass of the rocket) I want ...
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How do space probes find their way and how much fuel do they use to travel?
How do space probes find their way, for example, to explore dangerous planets like Jupiter or Saturn that have powerful magnetic fields? Do scientists control it from stations in NASA or they have a ...
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How was the external tank emptied in a TAL shuttle abort?
One of the numerous reasons RTLS was the least preferred choice is
For a safe separation, the ET must contain a maximum of 2% propellant remaining at Main Engine Cutoff (MECO).
How would TAL do away ...
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Why did the June 2016 SpaceX launch run out of propellant?
In other words, what caused SpaceX to miscalculate the amount of propellant required to safely land the booster. They had landed successfully on the drone ship in April. So what went wrong here? What ...
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Why do the Falcon 9 fairings have soot on them?
On nearly every SpaceX webcast since 2020 they explain that the Falcon 9 booster has soot on it because, during the entry burn, it flies through its own exhaust plume very quickly depositing the ...
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What is the value of SpaceX Starship 1200-ton propellant capacity? Would a fully refueled Starship be able to accelerate to Jupiter (for example)? [duplicate]
2200000N (1 Raptor) / 1,300,000*0.4 kg (Total weight adjusted to fuel loss) = 4.2 m/s^2 (acceleration)
Delta-V (to travel to Jupiter) = 9000 m/s
9000 m/s / 4.2 m/s^2 = 2,142 s (1 Raptor engine ...
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How much of LOX will have to be generated for SpaceX Starship to get back from 16 Psyche?
Mixture ratio for Oxygen/Methane is 3.6 to 1
Liquid oxygen temperature of -183°C
16 Psyche (in shade) -113.15°C (https://simple.wikipedia.org/wiki/16_Psyche)
Looks like the idea of bringing enough ...
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Important new additives to hypergolic hydrazine-based fuels since 1972?
In "Ignition! An Informal History of Liquid Rocket Propellants", John D. Clark in one of the chapters gives an overview of the then current state of hydrazine and hydrazine derivatives.
The ...
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How were inflatable fuel tanks for NASA supposed to work?
When the Washington State University researchers looked through the literature, they came across research that described the development of a bellows that took advantage of origami, the Japanese art ...
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How to account for burned fuel mass when calculating spacecraft acceleration?
I thought I could simply remove half of the burned fuel mass to account for the mass lost during the engine burn.
But I could not find a Newton's Second Law formula Calculator that would allow that, ...
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What engine cycle is best for a large lunar lander?
I'm specifically looking for an answer to whether a pressure fed or pump fed engine would be more feasible considering a mass of over 50T(metric, of course), and a single stage to descend and then re-...
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Calculating propellant mass from total impulse
I have a simple question about how to calculate the total propellant mass used by a satellite in space.
From Simulink, I have a graph of thrust VS time, so I could integrate this to calculate the ...
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How do propellant transfer technologies work?
I'm new to the aerospace world, and I was wondering how the ISS or other rockets were refueled in space. I've found some information, but most were patents and I wasn't able to understand them well.
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What is the most powerful solid rocket fuel (highest isp) and it's combustion temperature
I wanted to know what the most power full solid rocket fuel is. I do not mean theoretical once like metallic hydrogen.
Are solid rocket fuel mixtures prepared in a non-ideal mixture? In other words, ...
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Does Juno have enough fuel to push itself into a more elliptical orbit reaching out to Himalia? [duplicate]
Does the Juno probe have enough fuel to push itself into a highly elliptical orbit around Jupiter so that its apojove would be at Himalia's orbital distance to study Himalia better? Would a gravity ...
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What are better ways to deliver heat directly to propellant in a Thermal Rocket design for use in launch than UV such as in the Nuclear Lightbulb?
Most advanced, high-power engine concepts that I came across aren’t suited for atmospheric launch, so I got curious about what kinds of engines could launch a very heavy craft from the surface of a ...
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A hybrid micropropulsion system for CubeSats
I am curious about how much potential would a hybrid (electric & chemical) micropropulsion system have for CubeSats.
The chosen propellant is water due to its non toxic nature, cheap cost and high ...
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Nitrogen trifluoride as a high density oxidiser
Nitrogen trifluoride (NF3) is a liquid between 66K and 144K and has an incredible density of 1.885 g/cm2. It has a pretty great specific impulse, although combustion temp is a bit high, and AFAIK is ...
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Paraffin wax in solid motors
Paraffin wax is often used in (at least hypothetical) hybrid motors, mostly with N2O or HTP. Could it not, however, be used in a conventional configuration? Running at O/F of 12.4, 60 bar chamber ...
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How do you calculate fuel usage ratio for rocket acceleration vs deceleration using a fixed total amount of fuel?
If a rocket is accelerating and then decelerating to stop at a destination (not necessarily continuous acceleration), and you want to use a given total amount of fuel, how do you calculate the amount ...
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What rockets use a methalox propellant?
I’ve found that the SpaceX Raptor rocket engine and the BE-4 rocket engine use methalox (Liquid Methane and Liquid Oxygen), is there any other rocket engines that use a methalox.
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What is the best chemical rocket fuel from a purely specific impulse standpoint?
A variety of different rocket programs use a variety of different fuel types. Researching this, the main fuel combinations I saw were: RP-1 / LOX (SpaceX's Falcon rockets, early stage Atlas and Saturn ...
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How to calculate combustion temp? [duplicate]
I was reading about a propellant combination using ethanolamine(19.9% propellant fraction w/ 1% Copper Chloride) and 90% HTP(80.1%). I am trying to design a hypothetical engine around the propellant, ...
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Why isn't oil used for rockets? [closed]
Most people know that when you add oil to a fire, it grows rapidly and becomes more powerful. So, why isn't added into the propellant just before it comes out of the engine?
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Could a Mars rover go to Phobos or Deimos instead?
Could a Mars rover go to Phobos or Deimos instead of going to Mars? The choice is made after launch, and no further modifications can be made to the rover. Could it land safely? Up to what point could ...
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Ultimate fate of rocket propellant in space?
For many trajectories using engines with moderate ISP such as chemical or nuclear-thermal rockets, the exhaust velocity vector of various space operations is such that the rocket exhaust will end up ...
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What happens to the propellant in a wet dress rehearsal?
The Artemis 1 mission is going to do a wet dress rehearsal where the rocket will be filled with propellant and the launch sequence will continue until almost the last second. The launch sequence will ...
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What is the equation to find how much fuel you need to reach a velocity? [closed]
Theoretically, I need to launch a rocket, and I need to find how much fuel I need to reach a velocity however I do not know the equation.
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What is the equation for fuel equals distance for a rocket? [closed]
Theoretically, I am trying to launch a rocket from space and trying to figure out how much fuel I would need to get to a certain distance.
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Why is monopropellant used?
The most efficent fuel, liquid hydrogen, is a bipropellant. So, why don't we just use bipropellants? Some monopropellants, such as hydrazine, are toxic. Wouldn't it be easier to just use bipropellants ...