Кубенко В.Д., Янчевский И.В. «Аномальные частоты в полубесконечном цилиндрическом сосуде с жидкостью при динамическом возбуждении сферическим излучателем» Прикладная механика, 56, № 2, с. 18-35 (2020)

A semi-infinite circular cylindrical cavity filled with an ideal compressible liquid which contains a spherical body located near to its end is considered. The body surface radiates the periodic pressure with the given frequency and amplitude. The problem of determining the hydrodynamic characteristics of the system depending on the frequency of excitation and geometrical parameters is solved. The method of separation of variables, the translational addition theorems for the spherical wave functions, and the relations representing the spherical wave functions through the cylindrical ones and inverse are applied. This approach allows to satisfy all boundary conditions and to obtain the exact solution of boundary problem. The calculations are reduced to solving the infinite system of algebraic equations. Further, it is asserted that its solution obtained by the truncation method converges. Determination of the pressure fields and velocities is displayed that the considered system has the series of frequencies of excitation at which the acoustic performances can exceed several orders the amplitude of excitation. These anomalous frequencies differ from the frequencies inherent for an infinite cylindrical cavity with a spherical body. Thus, even in a case when the radius of spherical emitter is small, and therefore the anomalous phenomena in an infinite vessel are poorly expressed, in a semi-infinite vessel they can appear essentially.

Карлаш В.Л. «К вопросу о моделировании колебаний пьезокерамических резонаторов высокой мощности эквивалентной схемой» Прикладная механика, 56, № 2, с. 60-70 (2020)

The variants of the known electric equivalent Van-Dyke-type scheme for small and high power levels are estimated. The R, C, L model is compared and matched with AFCh of the radial vibrations of concrete piezoelectric disk. The proposed conception of accounting in calculations the only constant (frequency independent) values of dielectric, elastic and piezoelectric loss tangents does not conflict with the analytic and experimental results. The additive loss resistor for high power conditions influences at the resonance in lower degree than at the anti-resonance and must be switched on sequentially with shunting clamped capacity.

Максимюк В.А., Сущенко Е.А., Фетисов И.Б. «Методика измерения динамических характеристик исполнения музыкальных произведений на ударных инструментах средствами тензометрии» Прикладная механика, 56, № 2, с. 71-77 (2020)

The experimental technique for studying the temporal and amplitude characteristics of the music works performance on percussion is suggested. An idea of the non-isochronous rhythm in the Ukrainian folk dance music is confirmed experimentally. A role of intensity in forming the construction of running through and rhythmical pattern of the particular measures is demonstrated. The question is formed on the different types of interaction between the duration and intensity within the musical performance as a key means of musical expression in playing the percussion.

Михайленко В.В., Карнаухова Т.В. «Об энергетической теории коэффициента электромеханической связи при колебаниях пьезоэлектрических тел» Прикладная механика, 56, № 2, с. 120-129 (2020)

A definition of the coefficient of electromechanical coupling (СEMС) for the case of oscillations of the inelastic piezoelectric bodies is given. The effect of energy dissipation is taken into account by introduction of the integral loss characteristic. The definition of CEMC corresponds to the proposed by A.F. Ulitko energetic CEMC, which is interpreted as the limiting case when losses are neglected.