Questions tagged [shock-waves]
A shock wave is a type of propagating disturbance. When a wave moves faster than the speed of sound in a liquid, gas or plasma (a "fluid", in physics terminology) it is a shock wave. Like an ordinary wave, a shock wave carries energy, and can propagate through a medium. It is characterized by an abrupt, nearly discontinuous change in pressure, temperature and density of the medium. In supersonic flows, expansion is achieved through an expansion fan.
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Why does the airflow turn less when you extend further from the body?
In this answer, it says as follows:
Because "far enough" from the Concorde's nose, the path followed by the airflow is not affected by its presence and it's just a straight line. Close to ...
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How does the weak / strong shock solution work?
In this chart, you can see that there are 2 possible angles for a shock to be at when both the deflection angle and Mach number are the same.
Circled in red is the line of an object going Mach 2, and ...
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How will a normal shock forming on a wing create drag?
When you're going close to supersonic speeds, the air over the wing is actually getting accelerated to supersonic. When the pressure recovery area comes, this accelerated air turns into a shock ...
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Is it possible for a shockwave to reflect off of the ground, making the observer hear 2 shocks?
Is it possible for a shockwave from a supersonic aircraft to reflect off of the ground, forcing the observer to hear 2 shockwaves?
In this picture, the shockwave from this aircraft is shown to reach ...
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Will the 3D effect change shockwave angle/strength?
Similar to how the 3D relieving effect will change the shockwave angle (see above), will this same effect change the shock angle and strength further away from the body? As a shock goes through ...
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Why is there an area of different density right at the nose of a plane going supersonic?
A normal subsonic enough, but still compressible flow will compress when it gets to the planes nose. But in supersonic flow, there won’t be this compression. There will just be a shockwave which turns ...
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What happens in order to make a shock when the flow first turns?
Imagine you have a really zoomed in view of a 2d ramp, which is at 20 degrees. Zoom in on the exact point the ramp turns from horizontal to 20 degrees.
When the first supersonic air molecules reach ...
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Why are shockwaves allowed different angles at different distances from a body?
It's been (well) established that a shockwave can only be at the angle of the Mach cone. (I now understand this part). However, in this picture:
you can see that the shock is at 2 angles. I also ...
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Why will the flow turning angle be 0 (or close to) inside of the Mach cone?
(Disclaimer : This probably seems like my 56th question on the same topic, but this will be my last relating to Mach cone angle and shock angles, as I think I understand most of the topic)
So the ...
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Can a shock in certain circumstances be at a lesser angle than the Mach cone?
(Excuse the drawing quality)
What will happen if a shockwave has an angle less than that of the Mach cone?
In this picture, the black line represents the Mach cone. The orange line represents the ...
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Does the flow turning amount change as you get further away from an object?
Will the flow turning amount change as you get further away from an object? This answer explains why shockwaves will extend past the body that made them (good starting point). This question is asking ...
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Why does the angle of a shock change when the flow leaves the influence area of an object?
In this (great) answer, it says:
"far enough" from the Concorde's nose, the path followed by the airflow is not affected by its presence and it's just a straight line. Close to the nose we ...
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Why does the shock angle always seem to equal the "sound cone" angle?
(I'm going to use the term "sound cone" for the area you can hear an aircraft when it's at Mach ≥ 1, illustrated by this picture. Not considering the shockwave.)
So as explained in this ...
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Can a sound wave travel through a shockwave?
Say you have a scenario where there is a shockwave, and you sent a normal sound wave towards it. Could the sound wave travel through that shockwave? If so/not, why?
Would it depend on the strength of ...
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Why doesn’t the air expanding behind a shockwave reverse the effects of wave drag?
Wave drag is (from my understanding) the difference in pressure between the front and rear of an object due to shockwaves, making an opposing force. This needs higher pressure in front of said object ...
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