The interaction of the mixing zone between two gases of different
densities with compression waves and shock waves has been investigated.
The characteristics of the mixing zone in which the
Rayleigh–Taylor instability is developing have been analyzed. The
evolution of the mixing zone volume and mass during the accelerated
motion has been defined. A qualitative distinction in the evolution of
the mixing zone under the influence of a continuous deceleration
resulting from the interaction with the reflected compression
wave—shockless deceleration—is revealed as compared to
deceleration that is accompanied by appearance of a shock wave moving
through the mixing zone—shock-induced deceleration.