Questions tagged [nozzle]
Questions regarding the rocket engine nozzles, semi-open compartments of various shapes and sizes into which propellant components are injected by their own pressure or with a help of a turbine, often preheated and ignited to start a thermochemical reaction in the nozzle's combustion chamber, producing thrust with expansion into gases and ejecting them through the nozzle's exhaust as plumes, accelerating the rocket to high-mach velocities.
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Can a showerhead nozzle greatly simplify engine construction without serious performance panelities?
Here we established that a nozzle-less engine cannot achieve an exhaust velocity above the speed of sound.
But the fluids continue to accelerate after leaving the engine. Which brings us to the next ...
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Can a nozzle-less engine be made efficient by clustering?
I'm taking inspiration from phased array antennas, which can match the function of a directional dish antenna with several omnidirectional antennas.
The objective is to simplify engine construction by ...
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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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Knowledge needed to start rocketry hobby [closed]
I am a physics and rocketry enthusiast. I have the 9th Edition "Rocket Propulsion Elements" by George P. Sutton which is 700+ pages of professional and useful knowledge on rocketry and ...
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Is there any propellant for which a diverging-only nozzle would make sense? [duplicate]
It's been more than 15 years since I took Thermodynamics of Propulsion. By my recollection, a de Laval / converging/diverging nozzle accelerates a subsonic high pressure gas stream in the converging ...
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Which nozzle will fill the tank faster (or will they fill at the same rate), assuming that the tank is initially evacuated? for (C-duct -- CD nozzle )
There are two types of nozzles: Convergent duct and Convergent-Divergent nozzle. Both are operated under the same conditions for filling the same tank.
The answer says that the CD nozzle fills the ...
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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 to determine the law of plotting?
In the book on the calculation of Dobrovolsky's rocket engines, there is a graph according to which Xa counts. But is there a dependency on which this graph was ...
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Why Doesn't the cooling system on a rocket engine burn the fuel?
The cooling system on a specific rocket engine is usually a type of "pipe" that goes around the nozzle to not only keep the nozzle cool but also pre-heat the fuel. But the nozzle can reach ...
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What happens when the exhaust goes mach one
To create thrust and enough lift, you need a lot of mass thrown out at high velocities from a rocket engine. Most of the time this mass (exhaust) reaches over mach 1. I'm just curious whether this ...
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Rocket Nozzle Shape and Length
How is the efficiency of a particular nozzle shape with a given length calculated?
To clarify what I'm not asking for: I understand the idea behind the de Laval nozzle, where you constrict the flow ...
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Why should nozzles be perfectly expanded?
If I understand it correctly, the only problem with an overexpanded nozzle is (aside from technical difficulties) that the surrounding atmosphere puts pressure on the exhaust gases and reduces engine ...
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RS-25 Component weight
I need to determine the weight for specific components of the RS-25 Rocket engine. Namely the combustion chamber and nozzle separate from all other engine components?
I must have found hundreds of ...
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Nozzle contour estimation (Merlin 1D Vacuum)
I would like to run a fluid simulation of the diverging section of a Merlin 1D Vacuum engine. While most relevant parameters (such as expansion ratio, flow rate, and nozzle area) are readily available,...
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Does an overexpanded nozzle behave like a suction cup?
It is generally said that, to obtain optimal specific impulse, a nozzle should be just the right size that the exhaust pressure is equal to the ambient pressure. Quoting this answer, a relevant ...
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