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Questions tagged [thrust]

25 questions
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Thrust distribution of engine

I am studying the thrust distribution of jet engines. But I'm now a bit confused. In Rolls-Royce's "The Jet Engine" book, http://aeromodelbasic.blogspot.com/2012/05/thrust-distribution-distribution-of.html At the start of the cycle, air is induced…
Jono
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What is the equivalent moment of inertia of a two-pivot pendulum?

I am working on a system that consists of a hanging-pendulum thrust balance with two pivot points, one in the front and one in the back There is a heavy weight applied in the front. I can change the position of the center of gravity by applying…
idontexist
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2 answers

How efficient are jet engine thrust reversers?

Most reasonably sized commercial aircraft rely on jet engines for propulsion. Upon landing these aircraft use a number of means to come to a stop with the two most important being (I believe) mechanical brakes and jet engine thrust reversal. This…
Chris Mueller
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Thrust consideration in sprinkler and irrigation systems

In commercial fire sprinkler systems or large farm irrigation systems, is the thrust produced by the water a major design consideration? At what stage in the design process is this taken into account?
agentroadkill
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What is the equation to calculate the Thrust coefficient within a set of parameters?

In the book, Design of Liquid-Propellant Rocket Engines, there is a practice problem written as such. "Determine the design values of $(C_*), (C_f), and (I_s)_t$ for the engine thrust chambers of the stages of the hypothetical Alpha vehicle, with…
fftk4323
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5
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PWM flow control and thrust

If I have a water pump and a fast solenoid valve (can be open or closed) and turn on my pump at a constant voltage and apply pulse width modulation to my valve. Would the resulting thrust created at the water output be constant and can it be…
Mehdi
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Maximal thrust from water pump

For a small water pump like this one here, how can I roughly estimate how much thrust it would deliver considering the maximal pressure (PSI) and the flow rate (L/min). As a nozzle let's assume it is just a tube with a diameter d. I am a little bit…
Mehdi
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Compressing the air thrusted by an aircraft's propeller through a cone like tube

If I had an aircraft that used propellers for movement and took the air from the front running it through a tube that gets very small towards the end, would it have any impact on the speed? Would the aircraft get faster because the ejected air would…
Teslov Valentin
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How to calculate thrust from mass flowrate and velocity

How can I calculate thrust in Newton from mass flowrate and velocity? Please note,I have mathematical skills of 7 year old,the most complex task I can do is multiply and divide,I dont understand any equations.
wav scientist
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Thrust generated by a ship

While reading about airplane engines on the internet, it is common to find figures of their thrust, in kilo Newton. However, in the case of ships and naval vessels, when talking about the engine, the only parameter mentioned is the horsepower of the…
Harsha
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Which of these propeller configurations is most efficient?

All propellers shown in the figure above are identical and are operated at identical speeds with four separate (numbered 1 through 4 vertically) configurations illustrated. The physical distance between the cross sections of any two propellers is…
kbakshi314
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What is the relationship between the type of material(ex: steel, iron etc.), thrust and torque?

If I am drilling through bars of different material(ex: iron, steel etc.) of the same thickness and under the same conditions of drill operations(feed rate and rpm), how will the torque and thrust force measurement change for different materials?…
sumit808
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Does air pressure difference of intake exhaust contribute to jet thrust?

I know momentum of the airflow inside jet engine generates thrust, but what about the pressure difference in front of and at the back of the engine? The air sucking intake at the front has lower than atmospheric pressure and the exhaust has higher…
wav scientist
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Am I estimating thrust of a ducted fan correctly?

I'm asking if I'm doing this correctly. I've estimated the thrust of a ducted-fan model aircraft neglecting pressure changes across the duct as follows: $$F = Q * \rho * (V_e - V_0)$$ $$= Q * rho * (Q/A_e - Q/A_0)$$ $$ = 131 [cu. ft. / sec] *…
David Walden
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Propeller design

I see on internet, that aircraft propellers most effective blades angle only 15 degrees on every blade. Why propellers not use 45 degrees angle on propeller's blade that give more thrust on the aircraft rather than 15 degrees?
Shadow Clan
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