Sonic Boom & Condensation Trails: Explained

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A sonic boom occurs when an aircraft exceeds the speed of sound, creating a shock wave as it travels faster than the sound waves it generates. This shock wave results in a sudden increase in pressure and temperature, leading to the characteristic loud noise. The condensation trail, or contrail, forms due to the rapid cooling and pressure changes around the aircraft, causing water vapor to condense into visible droplets. This condensation can continue as long as the conditions allow, even after the sonic boom has been produced. Understanding these phenomena involves concepts from gas dynamics and the behavior of shock waves in airflow.
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Could someone try to explain to me the reason for the sonic boom that occurs during sonic flight and also the condensed water(?) coner(?) that appears behind the plane.
I've tried looking it up but I couldn't find any good explanations...
 
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ponjavic said:
Could someone try to explain to me the reason for the sonic boom that occurs during sonic flight and also the condensed water(?) coner(?) that appears behind the plane.
I've tried looking it up but I couldn't find any good explanations...

What do you know about Gas Dynamics? Have you ever heard about a Shock Wave, or do you know what's the Mach Number?

I'm only trying to get information to not saying things that seem strange or unknown to you.

Go here and tell me what do you think: https://www.physicsforums.com/showthread.php?t=45265
 
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ponjavic said:
Could someone try to explain to me the reason for the sonic boom that occurs during sonic flight and also the condensed water(?) coner(?) that appears behind the plane.
I've tried looking it up but I couldn't find any good explanations...

When an aircraft flies through the sky, sound waves bouce off of the plane. When the plane flies faster than the waves, the plane makes a sonic boom sound as it flies through the sound waves. The water that's condensed on the plane then comes off at the moment of the sonic boom.
 
Ok but this is no physical (not the word I'm looking for) explanation it's just an order of events.
When an aircraft flies through the sky, sound waves bouce off of the plane. When the plane flies faster than the waves, the plane makes a sonic boom sound as it flies through the sound waves. The water that's condensed on the plane then comes off at the moment of the sonic boom.
 
some answers...
What do you know about Gas Dynamics? Have you ever heard about a Shock Wave, or do you know what's the Mach Number?

I know the gas law, I have taken a peek at bernoulli's equation, I have understood that when flying faster than the speed of sound the density of air is allowed to be changed (is this important).
I know what a shockwave is and 1 mach is speed of sound while 5 mach is 5*speed of sound

The other forum thread you posted unfortunately did not help me. It spoke of some singularity which I couldn't see.
I wonder if the condensation continues to follow the plane or is it just as it breaks the barrier? Because the sonic boom continues after the plane has broken the barrier...
 
ponjavic said:
some answers...


I know the gas law, I have taken a peek at bernoulli's equation, I have understood that when flying faster than the speed of sound the density of air is allowed to be changed (is this important).
I know what a shockwave is and 1 mach is speed of sound while 5 mach is 5*speed of sound

The other forum thread you posted unfortunately did not help me. It spoke of some singularity which I couldn't see.
I wonder if the condensation continues to follow the plane or is it just as it breaks the barrier? Because the sonic boom continues after the plane has broken the barrier...

Nevermind, Ponjavic. The sonic boom is the consequence of a shock wave. Once the aircraft has reached the sound speed, the particles of air upstream the nose don't feel the presence of the aircraft structure. Thus all of them collide violently with the aircraft surface. It results on a strong increasing of pressure and temperature in the nearbies of the aircraft nose wall. The main property of such a shock wave is that suddenly increasing. In fact it is a discontinuity inside the flow field. That discontinuity is propagated across the flow field and the shock is convected along in an arrow shaped form just in front of the nose (have you ever seen that shape?). When you're on the street and hear the sonic boom, your ears are felling that jump of pressure produced by the shock extremes.

As the condensed water is concerned, I'm trying to clear it up to myself. But it is not an easy problem, because of that singularity you mentioned. I haven't understood that so far. The singularity of Prandtl-Gaulert is a singular effect of such flows into air. In fact, the condensation remains always if the pressure is small enough to condensate the vapor. The problem is behind the shock the pressure is increased, so that it would be hoped not to have any condensed vapor behind the shock.
 
Ok that gave me a little more insight, thank you =)
 
Air, like any gas can be compressed into a liquid, the action of the airfoil or wing compresses the air and forms the liquid water vapor. Condensation.

The sonic boom is the loud noise created when a high pressure wave followed by a low pressure wave of an aircraft traveling faster than the speed of sound, not just overcoming the sound barrier.

The sound of piled up compression waves converging at your ear.
 
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