The dynamic destruction of liquids manifests a number of unique features in contrast to analogous processes in solids. Among these are: 1) rise and development near the free surface of a large cavitation zone [1, 2] for impulsive loading by a shock wave; 2) formation of split foam structure layers [1]; 3) excess by orders of magnitude of the characteristic times of process development as compared to the duration of the loading wave [3, 4]; 4) uncertainty in location of the breakoff point and impossibility of fixing the final state of the specimen.The process of cavitation failure as a whole can be divided into the following stages [5]: growth of microbubbles, leading to formation of a cavitation zone; zone development up to formation of a foam type structure [3]; destruction of the foam due to dispersion. The cavitation zone is optically opaque for the major portion of its existence. The formation of large scale discontinuities in the liquid due to bubbles merging is an important part of the failure process, which, because of mathematical difficulties, has yet to be studied. Use of pulsed x-ray photography for study of optically opaque cavitation zones was proposed in [3]. The series of x-ray exposures of the cavitation process development allowed tracking the dynamics of the external state of the liquid specimen and study of the character of the process's dependence on loading parameters [6]. When used with special markers, this same method allows tracking the dynamics of mass velocities in the cavitation zone.The present study ,;vill describe methods for, and present results from, computer processing of x-ray exposures obtained in experiments on shock wave loading of a water specimen. The x-ray processing method involves transformation of the images into digital form, input of that data into a computer, and subsequent processing with a specially designed program, with the final goal of extracting quantitative information on the internal structure and dynamics of cavitation zone density in this stage of macrocavity formation. The results of processing a series of x-rays will be presented in the form of density fields in grayscale representation.Note that according to [6, 7], two possible cavitation development regimes exist. The process may be reversible, with the cavitation bubbles formed finally collapsing and the specimen becoming transparent again. When critical values of shock wave intensity are exceeded, the bubble growth process becomes irreversible, which leads to formation of a foam structure. The experimental results presented below on cavitation failure of a water specimen were obtained at loading parameter values close to critical.The essence of the method is division of the object into a finite number of elementary volumes, the density in which is calculated from the digitized x-ray data on the basis of absorption laws and photometric relationships. The process as a whole is symmetric relative to the shock tube axis, so we may limit ourselves to a mean density p(z, r). In the processing it is assum...

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This experimental investigation is devoted to bubble cavitation development in the samples of distilled water under the action of intense rarefaction waves. In the experiments two types of shock tubes were used, with the shock waves generated in liquid by (i) the impact of a piston onto an unmovable liquid, or (ii) moving a conductive disk accelerated by a pulsed magnetic field. An initial dynamics and parameters of microinhomogeneities were determined from the measured scattered radiation intensity (λ = 0.63 mcm) of a He-Ne laser. It has been found that the centers of ∼1.5 mcm size give an essential contribution into scattering. A total number of inhomogeneities is about 105 cm−3. An experimental analysis shows that at least a portion of microinhomogeneities represents microbubbles of free gas. The x-ray method allows us to determine an initial moment of liquid fracture and dynamics of its structure for a volumetric concentration of gas phase of 2%–4% and higher. The computer proceeding of the roentgenograms is presented.

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