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rickitek
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is the thrust equation F=MA applicable only in atmospheric condition? can we use this equation in vacuum or pressurized space, thanks!
Replace 'speed' by 'acceleration' in that sentence and it will be correct.rickitek said:so youre saying that the thrust produced by exhausting gas in both environment were the same, they only differ in speed of the vehicle because of friction(the speed of the vehicle in vacuum is larger than in pressurized)?
rickitek said:so youre saying that the thrust produced by exhausting gas in both environment were the same, they only differ in speed of the vehicle because of friction(the speed of the vehicle in vacuum is larger than in pressurized)?
So, ( forest for the trees ) doesn't that show you that the outside pressure can alter the thrust of a fluid exiting a container.rickitek said:of course there would be no thrust because outside and inside environment will be in equilibrium, the gas wouldn't flows out. what I am asking is if the thrust would change if the outside environment specifically pressure changes. or is the thrust also is dependent on the outside pressure,
thanks for your reply,
You initial inquiry says nothing about how the thrust is being accomplished, or specifically to what type of flow, compressible or not, choked flow, sonic, subsonic, what type of nozzle - convergent or convergent-divergent, upon which an answer can depend.rickitek said:is the thrust equation F=MA applicable only in atmospheric condition? can we use this equation in vacuum or pressurized space, thanks!
rickitek said:if that is correct, then it means that the amount of thrust generated by a jet in vacuum is also the same if the same jet is put in a pressurized space. because if we analyze it, it seems to me that that the amount of thrust generated in vacuum is bigger than in pressurized space because the resistance against the exhausting gas in vacuum is lesser than in pressurized space.
im not sure, just my analysis, correct me if I am wrong
rickitek said:if that is correct, then it means that the amount of thrust generated by a jet in vacuum is also the same if the same jet is put in a pressurized space. because if we analyze it, it seems to me that that the amount of thrust generated in vacuum is bigger than in pressurized space because the resistance against the exhausting gas in vacuum is lesser than in pressurized space.
andrewkirk said:What is the steel plate attached to?
If it's rigidly attached to the rocket, it'll reduce the thrust because the high-speed gas hitting the plate will provide a reverse thrust.
If it's not attached to the rocket, and a long way away, it'll make not much difference. If it's close, maybe some gas will rebound off the plate then strike the rocket and provide some extra thrust, but I imagine that would be pretty minor compared to the thrust of expelling the gases.
It doesn't matter what happens to the gas once it has left the rocket engine, unless it then strikes the rocket again, or something connected to the rocket.
tfr000 said:Yes. As a rocket rises through the atmosphere, its thrust increases slightly.
rickitek said:1. the thrust in low pressure environment is greater than in high pressure environment because the resistance or drag is less in low pressure environment than in high pressure environment.(assuming the jet/rocket carry its own oxygen, it doesn't suck air from the outside)
rickitek said:1. when the exhaust gas flows out the rocket nozzle. the only resistance to the exiting gases that i can think of is the pressure of the outside environment. with this in mind i conclude that the outside pressure indeed affects the thrust, am i right?
Each Space Shuttle Main Engine operates at a liquid oxygen/liquid hydrogen mixture ratio of 6 to 1 to produce a sea level thrust of 179,097 kilograms (375,000 pounds) and a vacuum thrust of 213,188 (470,000 pounds).
rickitek said:things that i know:
1. the thrust in low pressure environment is greater than in high pressure environment because the resistance or drag is less in low pressure environment than in high pressure environment.(assuming the jet/rocket carry its own oxygen, it doesn't suck air from the outside)
CWatters said:Yes.
http://www.nasa.gov/returntoflight/system/system_SSME_prt.htm
Brief explanation/basic maths here...
https://exploration.grc.nasa.gov/education/rocket/rockth.html
Nidum said:'Go for throttle up' - about halfway down page :
http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts115/launch/qa-leinbach.html
Thrust in a pressurized environment refers to the force that is generated by a propulsion system in a pressurized environment, such as a rocket or jet engine.
Pressure affects thrust by increasing the density of the air or fluid that is being expelled from the propulsion system, which in turn increases the force of the thrust.
The factors that influence thrust in a pressurized environment include the design and size of the propulsion system, the type of propellant being used, and the altitude and atmospheric conditions of the environment.
Thrust in a pressurized environment is typically measured in pounds (lbs) or newtons (N) using specialized instruments such as thrust stands or strain gauges.
Thrust in a pressurized environment has many real-world applications, including in space exploration, aviation, and transportation. It is also used in industrial processes such as oil and gas drilling and water jet cutting.