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Compared with deflagration, detonation doesn't need to have an external oxidizer. Oxidizers and fuel mix when deflagration occurs. Detonation is more destructive than deflagrations. In detonation, the flame front travels through the air-fuel faster than sound; while in deflagration, the flame front travels through the air-fuel slower than sound.
As explained above, a deflagration is a subsonic reaction, whereas a detonation is a supersonic (greater than the sound speed of the material) reaction. Distinguishing between a deflagration or a detonation can be difficult to impossible to the casual observer.
The radioactivity released at Chernobyl tended to be more long-lived than that released by a bomb detonation hence it is not possible to draw a simple comparison between the two events. Also, a dose of radiation spread over many years (as is the case with Chernobyl) is much less harmful than the same dose received over a short period.
Like light or sound waves, when a blast wave reaches a boundary between two materials, part of it is transmitted, part of it is absorbed, and part of it is reflected. The impedances of the two materials determine how much of each occurs. The equation for a Friedlander waveform describes the pressure of the blast wave as a function of time:
Plant bioacoustics refers to the creation of sound waves by plants. Measured sound emissions by plants as well as differential germination rates, growth rates and behavioral modifications in response to sound are well documented. [1] Plants detect neighbors by means other than well-established communicative signals including volatile chemicals ...
The phenomenon is exploited in pulse detonation engines, because a detonation produces a more efficient combustion of the reactants than a deflagration does, i.e. giving a higher yields. Such engines typically employ a Shchelkin spiral in the combustion chamber to facilitate the deflagration to detonation transition. [2] [3]
At the explosion of nuclear bombs lightning discharges sometimes occur. [40] Smoke trails are often seen in photographs of nuclear explosions. These are not from the explosion; they are left by sounding rockets launched just prior to detonation. These trails allow observation of the blast's normally invisible shock wave in the moments following ...
It states that the detonation propagates at a velocity at which the reacting gases just reach sonic velocity (in the frame of the leading shock wave) as the reaction ceases. [ 1 ] [ 2 ] David Chapman [ 3 ] and Émile Jouguet [ 4 ] originally (c. 1900) stated the condition for an infinitesimally thin detonation.