Journal of Dynamics and Vibroacoustics

Rotor vibration stands out as one of the primary causes of mechanical seal failure. However, classical dynamic seal models often would not be able to fully explaining the failure process. Therefore, the proposed dynamic model systematization, including the models developed by the authors, proves invaluable in predicting the dynamic behavior of seals during operation within specific turbomachines or explaining the causes of seal failure. The single-mass dynamic model can be used to study the operation of the contact mechanical seals and simple dry gas seals. Meanwhile, the two-mass dynamic model is used for the studding of operational processes in classical dry gas seals under complex loading. Additionally, the three-mass dynamic model finds application in studying the operation of various complex mechanical seal types. This model is used to accurately determine the range of normal operating conditions for such seal types and to identify the mechanism of leakage loss in the presence of excessive rotor vibrations.

New technologies are a significant factor in improving the efficiency of industrial enterprises. Traditional design methods do not fully meet the needs for technological equipment. A promising direction is hybrid engineering, which combines physical and virtual approaches into a unified process. The basis of this approach is reverse engineering and numerical modeling. The article illustrates the implementation of hybrid engineering through the example of creating a check valve. The results of laser scanning of the parts are presented, with the advantages and disadvantages outlined. The results of the hybrid approach to numerical modeling for noise level prediction are also provided. The necessity for further research to accumulate practical experience, reliable statistical information, verification and validation results, and a knowledge base has been identified. It is confirmed that hybrid approaches are the most promising for accelerated design and prediction of characteristics, allowing the identification of design flaws at an early stage and enabling optimization to meet the specified requirements if necessary.

The article presents the results of the development of a finite element resonator model of a tuning fork-type vibration level detector. The model is developed in the Ansys Workbench software product. Options for evaluating the characteristics of the resonator are proposed, including strength, modal, and harmonic analyses. A model of free damped resonator oscillations has been developed, including dynamic strength calculation in combination with a computational fluid dynamics module. The model makes it possible to estimate the frequency of resonator vibrations in liquids with different densities and viscosities. The simulation results are compared with laboratory experiments. The comparison showed a deviation in resonant frequencies of no more than 7%. The simulation results will be used to carry out structural optimization of the resonator geometry to expand the range of densities and viscosities of the working fluids of the level indicator.

Digital technologies are opening new horizons in the field of pneumohydraulic drives for technological equipment. This article examines the key issues and prospects in this area. The implementation of digital technologies significantly enhances the efficiency and accuracy of pneumohydraulic systems. The use of sensors, microcontrollers, and software provides more precise control over processes, energy consumption optimisation, and predictive maintenance. Digitalisation of pneumohydraulic drives is an inevitable step in the development of technological equipment, offering new opportunities for industry and innovation. Modern methods of data analysis, mathematical modelling, and machine learning algorithms are used for a successful implementation of this approach. Particular attention is paid to analyzing the application of digital technologies in pneumohydraulic drives of modern technological equipment, identifying key challenges faced by the industry, and determining promising development directions. The study considers new directions in the design of pneumohydraulic drives with a focus on the growing need for integrated sensors and other control devices. Recent advances in the design and implementation of pneumohydraulic drives relate to combined control of fluid flow supply and return to improve system dynamics, accuracy, and load sensitivity, where load effort is matched with drive pressure to increase efficiency. This review provides a detailed description of emerging trends in pneumohydraulic system research and gives an overall view of progress related to the digitalization of these systems. The basics of relevant sensor technologies and innovative approaches to integrating sensors into hydraulic and pneumatic systems are discussed.

To determine the operational boundaries of pneumatic brakes based on multistage axial compressors, recommendations have been developed for selecting the configuration and parameter values of the finite element flow mesh in these devices. The proposed recommendations allow for a reduction in the number of mesh elements in models of the compressor's inter-blade channels without decreasing the accuracy of determining the operational boundaries of pneumatic brakes. Testing of the developed recommendations has shown that their application enables more than a twofold reduction in the time required for the gas-dynamic design of pneumatic brakes.