Questions tagged [thrust]
Force produced by pushing against a reaction mass in space à la Newton's third law: "For every action there is an equal and opposite reaction." The thrust of a rocket engine is the forward force produced by expelling the exhaust mass (reaction mass) in the backwards direction.
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To what extent can a rotary detonation rocket engine (RDE) engine’s exhaust be “gimbaled” (trust vector control) by control of propellant flow?
Rotary detonation rocket engines produce a helical detonation wave which travels around a cylindrical combustion chamber before exhausting out the (nozzle-less) nozzle end.
Fuel is fed into the head ...
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What is the meaning of "negative thrust" in a grossly-overexpanded engine?
I recently reread this answer and noticed this term being used (quoted here):
At atmospheric pressure, the exhaust can only be over expanded up to a point before the engine begins producing negative ...
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How much thrust could radiators provide?
Usually heat is a waste - spacecraft use substantial mass to get rid of it via radiators.
But what if one uses it for thrust? Why not to make some dumb photonic engine out of it?
Obviously it would be ...
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What is the thrust to weight ratio of space shuttle without the SRB's? [duplicate]
Imagine a space shuttle without the two SRB's. When at launch configuration will the the shuttle's 3 RS-25 provide the thrust to lift the shuttle?
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Lunar Ascent Module - Center of Thrust
In a vacuum, in steady state, the Apollo Lunar Ascent Module is rated at 3500 lbF.
The combustion chamber is rated to run at 120 psia. The throat/aperture from the Combustion chamber to the nozzle is ...
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At what altitude is the ISP of a rocket in our atmospehre usually defined? Why is the vaccuum ISP not used for performance evaluations instead?
If we are defining ISP (Ceff/g) at sea level, wouldn´t it be easier to just use the ISP in vaccuum and avoid the varying but common atmospheric pressure parameter (Po) in the thrust equation and hence ...
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How are rockets able to keep their centers of mass in line with thrusters?
How can the thrusters of a rocket keep in line with its center of mass seemingly perfectly to not exert any torque and rotate the rocket? For torque to not be exerted, the force vector must align with ...
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Pressure Term in Rocket Thrust Equation
In the rocket thrust equation, as well as the thrust due to the mass flow rate of the exiting propellant, there is also an additional pressure term included. However I have noticed that this term is ...
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Engine most likely to be available in the next 80 years to accelerate a craft at 1G for 4 weeks [closed]
I am wondering what type of engine would most likely be available in the next 80 that can constantly accelerate a spacecraft at 1G. Preferably, it could accelerate it for 4 weeks.
The engine could be ...
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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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How can I find the predicted approximate altitude of a rocket based on simply the propellant, specific impulse, and propellant mass?(solid propellant) [duplicate]
I am getting all the inputs I outlined above, including burn-time which I could not mention above(character limit), from a small scale motor test. I know there are specific specific impulses for each ...
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Commercial Sources of variable thrust Rocket Engines [closed]
The project is to build a model rocket to take off and land vertically. Max height perhaps 100 feet.
Looking for a suitable engine which can provide variable thrust control and thrust vectoring which ...
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What is missing in the conversion of specific impulse from units of seconds to thrust/mass flow rate? [duplicate]
I was trying to get the Specific Impulse of the Saturn V engines, hoping for a value in N/kg/s, as I need to know the mass consumption rate per thrust value. Any and all sources give me the value in ...
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Is specific impulse and thrust maximum in vacuum or for exit pressure equals atmospheric pressure?
According to the thrust formulation of a rocket one can show, that maximum thrust is not delivered for pambient= 0 but for pambient=pnozzle_exit since then the momentum term is maximized.
But then I ...
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Wasn't it 1 engine out at liftoff, then another 5 were lost my the end of max-Q? [closed]
Here's a picture. 27 engines running out of 33.
Probably not as bad as you'd think. Yes there's less thrust, but the other engines will be able to run longer.
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