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Composite materials have a wide range of functional properties, which is ensured by using various technological methods of obtaining both the matrix or fillers and the composition as a whole. A special place belongs to the composition formation technology, which ensures the necessary structure and properties of the composite. In this work, a computer simulation was carried out to identify the main dependencies of the behavior of composite materials in the process of the main technological operations of their production: pressing and subsequent sintering. A polymer matrix randomly reinforced with two types of fillers: spherical and short cylindrical inclusions, was used to construct the finite element models of the structure of composites. The ANSYS Workbench package was used as a calculation simulation platform. The true stress–strain curves for tension, Poisson’s ratios, and ultimate stresses for composite materials were obtained using the finite element method based on the micromechanical approach at the first stage. These values were calculated based on the stretching diagrams of the matrix and fillers and the condition of the ideality of their joint operation. At the second stage, the processes of mechanical pressing of composite materials were modelled based on their elastic–plastic characteristics from the first stage. The result is an assessment of the accumulation of residual strains at the stage before sintering. The degree of increase in total strain capability of composite materials after sintering was shown.

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The paper presents the results of an experimental research and a numerical calculation of a multi-gap seal of a centrifugal pump. The experimental research allowed to obtain the characteristics' performance of the multi-gap seal at different operating modes, in dependence on the axial size of the chambers, pressure distributions' changes, and a leakage from the seal. Using finite volume methods, values of radial hydrostatic forces, pressure distributions and leakage values were obtained. The results of the numerical calculation were compared with the results of the experiment, which showed that they matched.

Актуальність дослідження багатошпаринних ущільнень має практичне значення для підвищення вібронадійності відцентрових насосів. У роботі розглядається модель однодискового ротора з ущільненнями. Визначаються змушені радіальні коливання ротора з урахуванням лінеаризованих інерційних, демпфірувальних, гіроскопічних, позиційних і циркуляційних сил, що діють на робоче колесо з боку потоку рідини в ущільненнях. Теоретичний аналіз доповнений числовим прикладом, наведені амплітудні і фазові частотні характеристики.Ключові слова: ущільнення, ротор, відцентровий насос, частотні характеристики.