The research described in this paper shows that main parameter of applied researches of acoustic cavitation are not the intensity the temperatures of plasma in the cavitation bubbles (power of sonoluminescence), but the power of pressure pulses, which they produce, and which cause destruction of phases existing in a liquid (power of erosion). The distribution of the density power of erosion in space can be the subject of numerically simulated, if it is assumed that process of multibubble cavitation is an ergodic process. For this the integral of pressure superposition from all bubbles of cavitation field at any point in space, must be approximated by the function of the pressure pulse on the surface of a single cavitation bubble, that pulsate with a period equal to the period of oscillations of the harmonic wave. This superposition can be described using a two metrics of space, which belongs to this point. The first – the average distance from this point until all points of the cavitation region, determines the average time of arrival at this point of the total perturbation of pressure. Second – means harmonic distance and determines the average coefficient of attenuation of this perturbation. The results of computational and laboratory experiments illustrate the adequacy and the applicability of model. The model makes it possible to quantitatively compare the results of physical and chemical effects of cavitation in the any liquids in the reactors of any size and design. The model also gives a sufficient degree of accuracy and reliability of performing the technical calculations for the design of such devices and the possibility to make comparative assessments of the different reactors.