Physics of a convergent nozzle

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  • #26
boneh3ad
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This is precisely why I asked if you've ever taken a course on fluid dynamics and/or compressible flow. I am trying to figure out where your base-level knowledge is and where your misconceptions arise. It will be much better for you if you go on a guided exploration of this topic than if I just blurt out the answer here.

So, I ask again:
  1. Have you taken a fluid dynamics course before? What about compressible flow?
  2. Why do you think that, in a choked nozzle, changing upstream conditions will not affect the downstream flow?
  3. What exactly do you think choked means? If you have a converging-diverging nozzle, can you give a rough sketch of the Mach number along the length of the nozzle, starting from the reservoir and going all the way through to the exit plane (assuming the nozzle is operating ideally)?
 
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  • #27
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As far as I know, choking means no change in downstream while the condition at the upstream may increase because the velocity has attained its maximum speed at the throat. That's all I know.
And I must admit that I haven't taken any course on fluid dynamics ever separately. I am guessing based on what I have studied during my college years in aerodynamics.
 
  • #28
boneh3ad
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Aerodynamics is fluid dynamics. Air is a fluid. You still haven't answered all of my question, though.
  1. Have you taken a compressible aerodynamics course (since it appears you have some sort of aerodynamics background)?
  2. What makes you think that changing the upstream conditions results in no change in downstream conditions in choked flow?
  3. Can you give me a rough sketch of what you think the Mach number, pressure, and temperature are doing in a converging-diverging nozzle?
If you really do have an aerdynamics background, you ought to at least be able to discuss this a little in a way that I can help you discover why your definition of choked flow is wrong, but you have to meet me halfway here.
 
  • #29
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I have background in physics. No specialisation in fluid dynamics.
 
  • #30
boneh3ad
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  • #31
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Kindly supply some net links that I can download directly.
 
  • #32
boneh3ad
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I am unaware of any online resources that are as good as those books.
 
  • #33
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At least give me some that can help me to get primary information.
 
  • #34
boneh3ad
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It used to be that potto.org had some incomplete, free, online textbooks available on these topics. They were okay... not great, but better than random stuff on the internet. It looks like all of their PDFs are missing but you could still browse the HTML versions. I can't guarantee that the texts are complete, and they aren't as good as the resources I already suggested.
 

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