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Modern development of computing systems and technologies allows to organize the construction of a generalized computational experiment in modeling problems of computational gas dynamics. The construction of such an experiment is based on numerical parametric studies and the solution of optimization analysis problems. Solving such problems implies a multiple solution to the direct problem of numerical simulation of a gas-dynamic process with different input data, where different sets of defining parameters are used as input data. The defining parameters of a class of problems, such as Mach number, Reynolds number, geometric parameters, etc., vary in certain ranges with a certain partitioning step. As a result, the resulting solution is a multidimensional volume of data. To analyze this volume, visualization is necessary. The paper attempts to systematize and briefly describe some types of visualization problems arising from processing the results of a generalized computational experiment. The aim of the work is to begin a broad discussion of the tasks of visualization and methods for their solution in a generalized computational experiment.

SUMMARYThe approximation of reduced linear evolution operator (propagator) via dynamic mode decomposition (DMD) is addressed for both linear and nonlinear events. The 2D unsteady supersonic underexpanded jet, impinging the flat plate in nonlinear oscillating mode, is used as the first test problem for both modes. Large memory savings for the propagator approximation are demonstrated. Corresponding prospects for the estimation of receptivity and singular vectors are discussed. The shallow water equations are used as the second large-scale test problem. Excellent results are obtained for the proposed optimized DMD method of the shallow water equations when compared with recent POD-based/discrete empirical interpolationbased model reduction results in the literature.

The use of modern polymeric materials as dielectrics makes it possible to increase operational characteristics of the elements of various electric power and electronic devices. The necessary combination of interconnected values of permissible electric field strength and maximum operating temperature is crucial when choosing a particular polymer material. The relationship of these parameters is nonlinear due to the nonlinear dependence the electrical resistivity and the thermal conductivity coefficient on temperature of the polymer material. This relationship can be represented in a closed analytical form of integral relations in which the variable limit of the integrals is the desired function describing the temperature distribution in the dielectric layer. A quantitative analysis of these ratios for five different polymeric materials with known electrothermal characteristics has been carried out. The results of calculations of the temperature state of the dielectric layer and the distribution in the layer of the absolute value of the electric field intensity are given. The presented results can be used to justify the choice of a particular polymer material as a dielectric in the designed devices.