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User talk:Itskbcfd

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Revision as of 08:05, 1 December 2023 by Itskbcfd (Talk | contribs)
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Welcome to CFD-Wiki! We hope you will contribute much and well. You will probably want to read the help pages. Again, welcome and have fun! Jola 00:11, 1 December 2023 (CET)

FLUID MECHANICS OF A CALM EXPLOSION

Yesterday while I was scrolling through some YT Shorts, I came across a video of Neil deGrasse Tyson, who was talking about the weird nature of the explosion, where he, as a physicist and witness of the event, could not locate any shockwave in the entire process and that surprised him. As a reason, he said about “deflagration waves”.

So what the heck is this wave? And was the 9/11 explosion fake or something? Absolutely no!

Deflagration is not what we speak of as an explosion. Compared to the natural interpretation of explosion, we often refer to detonation, whereas it has a far more timid sibling called deflagration. Deflagration may be defined as the explosion occurring when the flame front traverses across the conduit (pipe/duct/chamber) at velocities lower than the speed of sound. Detonation occurs when the flame front attains a velocity of more than one and pressure of about 2 MPa. In many cases deflagration may turn to detonation and the flame front hits the shockwaves, called DDT (Deflagration to Detonation Transition).

Here shockwaves act contrary to the nozzle as high pressure generated by the shockwave compresses the entire flame and the surrounding fuel, thus leading to the acceleration of the flame and the substances to higher velocities. When the fuel is atomized (subdivided into smaller droplets) the flame front comes under check, due to uniform combustion and the absence of air-fuel-rich pockets that shoot up detonation. Hence atomized fuel never goes up to the level of detonation and hence when scientists measure the entire air-fuel interaction and aerodynamics phenomena no shockwave is found.

Hope this post finds you well! I will be eager to learn more in this regard from the community!

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