Questions tagged [propulsion]
Systems for propelling a spacecraft from one place to another, such as rockets.
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Combustion stability for the second stage of Sea Dragon
I was listening to a video about SHLV's (Super Heavy Launch Vehicles), and Sea Dragon's first stage engine was mentioned.
In terms of combustions stability, the suggested fix would be large combustion ...
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How often does a CubeSat leverage its ADCS?
I'm wondering how often an Earth observation-focused CubeSat (6U - 27U) would leverage its onboard Attitude Determination and Control System (ADCS).
Would it be employing its ADCS to optimize every ...
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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 later this year. Notably, the lander uses liquid methane as fuel and liquid oxygen as the oxidizer, and it will rely on this combination ...
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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 is stage 2 propelling the spacecraft forward? [closed]
A decent response on how the burning process works but how does this glowy burner push the spacecraft
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Why wasn't SpaceX heavy rocket tested thoroughly on ground before being sent to space?
I do not know how much testing SpaceX did before launching their heavy rocket but it to blow up 3 mins later and call is a success seems a bit misleading. I understand they gathered data but to what ...
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Closed Loop Space propulsion
While browsing for Space propulsion found this book :
https://www.knygos.lt/lt/knygos/closed-loop-space-propulsion-new-faster-approach-2e4zy/
Closed Loop Space Propulsion New Faster Approach : The ...
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Is Electromagnetic Propulsion Like Radiation Pressure propulsion?
while browsing for new propulsion methods I found the following interesting:
https://en.wikipedia.org/wiki/Radiation_pressure
"Radiation pressure (also known as light pressure) is the mechanical ...
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Do full flow rocket engines still use injectors? If so, how? How exactly are the oxidizer and fuel sent into the combustion chamber?
I'm learning about rocket engines and full flow engines, and I'm a little confused about what goes on in the combustion chamber. It was my understanding that injectors were pretty much necessary to ...
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Propellantless propulsion in gravity field
I have a proposal for a following propellantless maneuver. It is propellantless in sense that no mass is lost from spacecraft.
It is not reactionless as spacecraft interacts with planet through ...
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What space applications could benefit from batteries with much higher power densities than the common Li-ion type?
This Australian company claims the development of the Graphene Aluminium-Ion Battery that is up to 70 times faster in charging and has up to 3 times more battery life than current Lithium-Ion ...
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What would be the most fuel-efficient propulsion solution to accelerate a 100-ton piece of NEO asteroid towards Earth?
We need acceleration to about 300-500 m/s relative to an NEO asteroid - to get to an LEO.
What is needed is the lightest package possible, that includes engine, fuel tanks, control module and ...
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Lorentz force space propulsion
While browsing for Space propulsion, I've found the following article
As shown in Figure 2, the conductor I0 gets through the coil L0, and they are fixed together and form a system. a is the main ...
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Can Nuclear Pulse Propulsion (Project Orion) accelerate a 100,000 ton M-type (metallic) asteroid to a LEO? [closed]
Project Orion: specific impulse in the range of 6,000 seconds.
For example – Starship Interplanetary (SpaceX):
Max Fuel (after refueling at orbit) - 1,950 ton
Fuel left after arriving at NEO asteroid –...
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Advice on ionic thruster
I am a high school student, and this year our school requires us to do this Year-long project, I chose building ionic thrusters as my project's first choice.
My question is, which type of ionic ...
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Has there ever been a fully-reusable big-dumb-booster design proposed?
I know of fully expendable Big Dumb Boosters, as well as "smart" reuse in systems like NEXUS (all versions) and their contemporaries, what I'm trying to figure out (after hours of sorting ...
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Main engine gimballing in Saturn V
The first stage of Saturn V has 5 main F-1 engines, but only 4 of the outer engines can gimbal and the engine at the center was fixed (Source : https://youtube.com/clip/...
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How can I derive Starlink specs looking at the incident of February 2022?
I am trying to calculate and speculate the specifications of Starlink satellites (mainly related to propulsion) based on the accident on the 3rd of February 2022. There are multiple sources that ...
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What is the most promising fusion technology for rocket propulsion?
Given current fusion technology (barely above q=1 as of the 12/12/22), is a fusion plasma torch rocket engine viable?
I'm asking in terms of basic science, not engineering, as I know this would ...
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The costs of a single SLS solid fuel rocket booster
Why didn’t Nasa cluster four solid fuel shuttle boosters around an Atlas V booster. The thrust would be substantially more than that of the SLS, with no fueling problem on the launch pad. It would be ...
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Are there any proposals for propulsive debris deorbiting which address basic requirements for efficiency?
This illustration shows many of the challenges using propulsive deorbiting:
https://www.smithsonianmag.com/air-space-magazine/34_aug2017-cleaning-up-space-junk-180963932
The trust line of the tug is ...
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Thrust to weight of large solid fuel boosters
I have been looking at examples of large solid fuel rocket boosters or first stages used for space launch, such as P80, the Space Shuttle SRB, the various versions of Graphite-Epoxy-Motor, the solid ...
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How to find cost data for commercially available spacecraft components?
I'm trying to research how much it should cost to build a small spacecraft, but it's super hard to find good information on the cost of various components. Can anyone suggest any good resources? For ...
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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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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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Resources for Rocket Propulsion
I am a Mechanical Engineering student who is very much interested in Rocket propulsion. Lately I have been searching for good resources to learn concepts about rocket propulsion. I'd be glad to get ...
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rocket propulsion elements [closed]
i tried to solve the following problem
this rocket engine area is cut off at 50% of the exit area, calculate the new Mach value.
data old engine:
P1=2068Mpa , chamber temp 2222k , flow mass 1kg/sec ,...
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In Apollo hardware, why were sump tanks needed?
I'm looking at the Apollo CSM Propulsion Systems. These were bi-propellant hypergolic systems. However, for some reason each type of propellant was divided into a storage and sump tank.
For example, ...
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Do cold gas thrusters fueled by supercritical CO2 have a higher Isp than those fueled by liquid CO2?
The private space company Pixar has developed an autonomous space vehicle (Wall-e) propelled by a cold gas thruster Hand-Held Maneuvering Unit as demonstrated in this press release:
From https://...
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Is there any major difference between acceleration of solid propelled and liquid propelled rockets during launch
Few days ago, ISRO launched its PSLV-C53, which had solid first stage. (Clip here)
Also, the SpaceX's starlink launched on 24th July, 2022, having liquid first stage. (Clip here)
Is there any major ...
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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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Variant of the Tsiolkovsky rocket equation including engine specific power and efficiency, can anyone help me under stand how this works
First of all this code is not mine I am trying to understand how the equation for m_u works. This comes from a master thesis called Trajectory design for a Titan mission using
the Direct Fusion Drive ...
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Could the Space Shuttle launch with two engines?
In a movie, they need to launch the Space Shuttle, but one engine is not ready to go in time, so they decide to launch with the booster and two of the shuttle's engines - Could the shuttle Launch with ...
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How exactly does depressurization work in a solid rocket motor?
How does the extinction process actually work in a solid rocket motor?
Most people initially always read that once a solid rocket fuel is ignited there is no way to actually stop its operation until ...
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Can ion propulsion system be used to maintain lunar orbit?
I am doing research on propulsion systems and it was suggested that I use an ion propulsion system for a theoretical satellite I am tasked with designing, I need to maintain orbit for three years ...
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What should be the mission plan in order to reach TITAN (SATURN) by a group of 15 people for Scientific Exploration? [closed]
I am working on a project where we have to design a
Mission to TITAN by Digitally construct and document the development of a six-month long human settlement on Titan (Moon), bearing the capability to ...
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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 ...
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Why did the recent Elana41 mission fail?
On February 10, 2022, the Astra LV0008 rocket failed mid-flight, shortly after stage separation. It appeared to ignite and then shut off repeatedly, while also spinning out of control. Do we know what ...
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What is wrong with hydrazine as a monopropellant?
While answering a question about if N2O was a practical monopropellant, I found that hydrazine was considerably more efficient. So, why do people want to replace it with N2O, if hydrazine is more ...
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Are VASIMR + Arcjet engines feasible for orbital transfers on Mars?
The VASIMR engine is an electric propulsion system that has been lauded for its ability to cut down on interplanetary transfers. While it requires a high power source (in the range of 200kW), it is a ...
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Calculating time for several transfer orbits
I was watching a video that displayed how the time to get to Mars varied with the production of varying delta-v and was looking for the mathematics behind such a calculation. Here is the link to the ...
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Thrust needed for Ion Thruster Lift off from Earth surface
I've been calculating the needed mass flow rate for a hypothetical ion rocket, lifting off from Earth's surface and propelled with a Dual-Stage 4-Grid ion thruster. Data given: mass of the spaceship /...
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Why can't you travel to Mars in a straight line?
I had two questions regarding choosing a path to Mars. Firstly:
I wanted to have a look at the mathematics behind the reason as to why we choose Hohmann's transfer over a journey that is a straight ...
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What is the equation that relates delta v of a rocket to time taken to complete an orbit?
I wanted to see how the delta-v produced by a rocket affects the time it takes to complete a certain orbit. So what is the equation that relates these two quantities?
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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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From which NASA publication originates/where can I find a higher resolution version of this SSME flow diagram?
This came up when I was taking a look at Endeavour over in LA. Where can I find a readable version of this full flow diagram (valves, control systems, and everything)?
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Why aren’t vacuum engines turned on after Mach 1?
In rockets, smaller nozzles are used at lower altitudes because atmospheric pressure would cause problems by pushing air into nozzles with higher expansion ratios.
However, it seems to me that once ...
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