This study examines the dynamic characteristics and improvement of control methods for impulse hydraulic shock mechanisms used in high-performance hydraulic systems. The work focuses on eliminating the common discrepancy between theoretical and actual output parameters caused by inefficient processing of control signals. A mathematical model has been developed that describes the displacement, velocity, and acceleration of the actuator, taking into account nonlinear fluid dynamics and changes in external load. Based on this model, improved control methods are proposed, aimed at increasing system stability, reducing response errors, and improving the energy efficiency of the impact action. Numerical simulation has shown that adaptive input signal shaping significantly improves the system’s performance. Under identical modeling conditions, the proposed logic-based control method reduced the normalized force deviation by approximately 15–20% compared with the conventional control scheme. A logical structure for generating the input signal X(t) has been developed, ensuring more precise synchronization of dynamic processes. The results obtained contribute to the development of control methods for hydraulic shock mechanisms and propose improved algorithms applicable in engineering systems where high accuracy and reliability are required. Future plans include experimental verification of the proposed solutions on physical prototypes, as well as refinement of the mathematical models to account for the compressibility of the working fluid and real-time load changes.
The paper studies the effect of residual stresses on the microstructure and mechanical properties of metal coatings formed by electrolytic rubbing. The dependence of the internal stress level on the current density, anode rotation speed, electrolyte composition and deposited layer thickness is established. It is shown that with an increase in current density from 50 to 100 A/dm² and a deposition rate of up to 16.6 μm/min, residual stresses vary within 23–34 kg/mm². The addition of ascorbic acid, nickel and manganese chlorides promotes an increase in stresses by 5–10% and simultaneously increases the microhardness of the coatings. A decrease in residual stresses is noted upon reaching a layer thickness of 0.03–0.04 mm, followed by stabilization at a level of 10–12 kg/mm². The results of the work can be used to optimize technological modes of restoration and hardening of agricultural machinery parts, ensuring increased accuracy and quality of metal coatings.
This study investigates the dynamic behavior and surface integrity optimization of low-frequency hydraulic impulse systems operating under cyclic loading conditions. Particular attention is paid to the performance of the hydraulic module rod, which is subjected to repeated dynamic impacts during system operation. The influence of surface roughness, residual stresses, and microhardness on vibration stability and durability of friction pairs is analyzed. A dynamic mathematical model describing pressure variation, piston motion, and energy transfer within the hydraulic impulse chamber is developed. The model is implemented in the MATLAB/Simulink simulation environment for numerical analysis of transient processes. Experimental studies were conducted on cylindrical rod-type specimens made of 30KhGSA alloy steel processed using rotary multi-blade turning technology. The experimental results demonstrate that optimization of machining parameters significantly improves surface quality and reduces vibration amplitude of the hydraulic impulse system. The proposed modeling approach enables prediction of system dynamic behavior and provides a basis for improving operational stability. The obtained results confirm that the integration of advanced machining technologies with digital modeling tools can increase the reliability and efficiency of hydraulic impulse systems used in industrial applications.
This study aimed to cool photovoltaic panels (monocrystalline and polycrystalline) using advanced cooling techniques with pure water and copper nanoparticles. The problem addressed by the current study is the high temperature in solar panels, and this problem is addressed by using one of the advanced cooling methods using nanomaterials. The high temperature harms the performance of photovoltaic panels, so cooling them is important until the high temperature leads to a decrease in their efficiency. Nanoparticles have been identified as one of the most effective methods in cooling photovoltaic panels because of their properties that can help improve the efficiency of photovoltaic panels. This study aimed to cool photovoltaic panels (monocrystalline and polycrystalline), and K – type thermometers were used to measure the side temperature. The back of each panel every half hour and the use of a Multi meter digital to measure current and voltage per half hour and a solar radiation meter to measure the intensity of solar radiation. In general, monocrystalline panels achieved better than polycrystalline panels and the best improvement of output power was when using Nano fluid at a concentration of 5%. The output power of monocrystalline and polycrystalline panels (76, 81, 85, 89W) (65.48, 70, 74.5, 76W) respectively when using distilled water and Nano fluid at a concentration of (1, 3, 5 %).
This paper investigates the role of phonon dynamics in the solid crust of neutron stars and their connection to large-scale structural instabilities. Electron capture reactions in the dense outer layers of compact stars generate excited nuclei, which may transfer their energy to the lattice in the form of phonons. These vibrational modes affect the elastic response of the crust, modifying its stress–strain behavior under extreme astrophysical conditions. Using fundamental parameters such as Young’s modulus, density, and sound velocity, we estimate phonon frequencies, wave numbers, and lifetimes across different crustal layers. Numerical analysis indicates that phonon excitations are capable of storing elastic energy and may act as precursors of sudden stress release events. A special focus is given to pulsar glitches, with the Vela pulsar serving as a representative example. The comparison between calculated phonon energies and observed glitch energetics suggests that collective phonon processes could contribute to the mechanism of these abrupt rotational irregularities. By emphasizing the importance of lattice dynamics in neutron star models, this work provides the first quantitative estimates linking microscopic phonon excitations with macroscopic glitch energetics, thus contributing to a deeper understanding of how nuclear-scale transitions manifest as observable astrophysical signals. These findings can contribute to future models of neutron star crust dynamics and related astrophysical observations.
