Dissipation Parameter Research Articles

Tetrahybrid nanoparticles through squeezed channel with inclined Lorentz forces

Heat exchangers, nuclear power plants, and other engineering and manufacturing operations all involve high temperatures. These systems have a very big temperature gradient, which has a substantial impact on the fluid's transport characteristics. Under such circumstances, using the linear Boussinesq approximation and taking into account the constant thermophysical parameters for the ambient liquid become meaningless. Thus, under the impact on the angled magnetic field and joule heating, the radiative convection flow of the blood-based tetrahybrid nanoliquid in a squeezing channel is examined in this work. The base fluid that contains the distributed alumina, gold, silver, and titania nanoparticles is blood. Through suitable transformations, the partial governing equations were decreased into nonlinear ordinary differential equation's, which are then resolved mathematically applying the fourth-order accurate BVP4C technique. The increase in the viscous dissipation parameter corresponds toward the notable elevation on the blood temperature profile. The rate of heat transfer 57.4519% improved in Au-Ag-Al2O3-TiO2/blood than that of pure blood.

Energy distributions of Frenkel–Kontorova-type atomic chains: Transition from conservative to dissipative dynamics

We investigate energy distributions of Frenkel–Kontorova-type atomic chains generated from large number of independent identically distributed (iid) random initial atomic positionings under two cases. In the first case, atoms at the free-end chains without dissipation (conservative case) are only coupled to one other atom, whereas each atom inside the bulk is coupled to its 2 nearest neighbors. Here, atoms located at the chain are all at the same type. Such kind of systems can be modelled by conservative standard map. We show that, when the coupling is non-linear (which leads chaotic arrangement of the atoms) for energy distribution, the Boltzmann–Gibbs statistical mechanics is constructed, namely, exponential form emerges as Boltzmann factor P(E)∝e−βE. However, when the coupling is linear (which leads linear arrangement of the atoms) the Boltzmann–Gibbs statistical mechanics fails and the exponential distribution is replaced by a q-exponential form, which generalizes the Boltzmann factor as P(E)∝eq−βqE=[1−(1−q)βqE]1/(1−q). We also show for each type of atom localization with N number of atoms, β (or βq) values can be given as a function of 1/N. In the second case, although the couplings among the atoms are exactly the same as the previous case, atoms located at the chain are now considered as being at different types. We show that, for energy distribution of such linear chains, each of the distributions corresponding to different dissipation parameters (γ) are in the q-exponential form. Moreover, we numerically verify that βq values can be given as a linear function of 1/∑n=1N(1−γ)(n−2). On the other hand, although energy distributions of the chaotic chains for different dissipation parameters are in exponential form, a linear scaling between β and γ values cannot be obtained. This scaling is possible if the energies of the chains are scaled with 1/(1−γ)−N. For both cases, clear data collapses among distributions are evident.

ANALYSIS OF THE CAUSES OF CYLINDER HEAD FAILURE OF INTERNAL COMBUSTION ENGINES

The problem of failure of the cylinder head of an internal combustion engine is considered. The factors influencing the reliability of the cylinder head over a given service life are analyzed. Among the areas that suffer the most are considered: partition between valves and between the valve and the nozzle, exhaust channels, attachment points, the plane of the surface that is in contact with the block. An analysis of existing works was carried out. Usually, the issue of reliability of a separate zone is solved, about which you can find many articles and patents. To date, there are no known works that comprehensively consider the problem of the reliability of all problem areas related to the cylinder head. This work describes the nature of the influence on the stressed state of the cylinder head from various factors: temperature loads, loads from the pressure of the working body in the cylinder, loads arising during fastening. Ways to solve problems with the reliability of individual elements exist and are being solved by many researchers, but the expediency of their implementation is ambiguous. Thus, improving heat removal from the hottest surfaces can lead to an increase in the share of influence from other factors. Solving the problem of reliability requires comprehensive consideration and a comprehensive approach. Thus, when modernizing or developing a new design, it becomes mandatory to carry out a calculation study taking into account the most complete range of factors affecting the system, which combines all the constituent elements included in this node. Modern engineering analysis systems allow such studies to be performed. It is also important to have sufficient knowledge about the properties of materials, which significantly affects the quality of the results of calculation studies. The change in heat dissipation parameters over time can be taken into account with the help of boundary conditions, which will allow us to study how the cylinder head will behave after some time of operation.

Stagnation point flow of hybrid nanofluid driven towards a sinusoidal-radius permeable circular cylinder

ABSTRACT Recent advancements in nanofluid technology have emphasized the potential of ternary hybrid nanofluids (THNFs) to significantly enhance thermal and hydrodynamic properties. The implementation of a wavy sinusoidal cylinder is proposed as a novel approach to optimize heat transfer in a variety of engineering applications. This study focuses on analysing the flow and thermal behaviour of TiO2-Al2O3-MoS2/Kerosene oil a THNF around a circular cylinder with a sinusoidal radius, demonstrating enhanced heat conduction capabilities compared to conventional hybrid nanofluids. The governing equations, formulated as partial differential equations, are solved using the bvp4c solver. The study reveals that the shape of nanoparticles plays a crucial role in heat transfer efficiency. Specifically, when the solid volume fraction increases from 1% to 3%, brick-shaped particles exhibit the lowest heat transfer enhancement of 25.80%, while blade-shaped particles achieve the highest enhancement of 68.24%. Additionally, the heat transfer coefficient improves from 1.5% to 1.8% across different nanoparticle shapes under varying dissipation parameters. Similar trends are observed in the reduction of drag force with changes in the velocity slip parameter. These findings underscore the significant impact of nanoparticle shape and volume fraction on the thermal performance of THNFs, offering valuable insights for optimizing heat transfer systems in engineering applications.

Enhancing (quasi-)long-range order in a two-dimensional driven crystal.

It has been recently shown that 2D systems can exhibit crystalline phases with long-range translational order showcasing a striking violation of the Hohenberg-Mermin-Wagner (HMW) theorem, which is valid at equilibrium. This is made possible by athermal driving mechanisms that inject energy into the system without exciting long wavelength modes of the density field, thereby inducing hyperuniformity. However, as thermal fluctuations are superimposed on the non-equilibrium driving, long-range translational order is inevitably lost. Here, we discuss the possibility of exploiting non-equilibrium effects to suppress arbitrarily large density fluctuations even when a global thermal bath is coupled to the system. We introduce a model of a harmonic crystal driven both by a global thermal bath and by a momentum conserving noise, where the typical observables related to density fluctuations and long-range translational order can be analytically derived and put in relation. This model allows us to rationalize the violation of the HMW theorem observed in previous studies through the prediction of large-wavelength phonons, which thermalize at a vanishing effective temperature when the global bath is switched off. The conceptual framework introduced through this theory is then applied to numerical simulations of a hard-disk solid in contact with a thermal bath and driven out-of-equilibrium by active collisions. Our numerical analysis demonstrates how varying driving and dissipative parameters can lead to an arbitrary enhancement of the quasi-long-range order in the system regardless of the applied global noise amplitude. Finally, we outline a possible experimental procedure to apply our results to a realistic granular system.

An Earth Encounter as the Cause of Chaotic Dynamics in Binary Asteroid (35107) 1991VH

Among binary asteroids, (35107) 1991VH stands out as unique given the likely chaotic rotation within its secondary component. The source of this excited dynamical state is unknown. In this work, we demonstrate that a past close encounter with Earth could have provided the necessary perturbation to allow the natural internal dynamics, characterized by spin–orbit coupling, to evolve the system into its current dynamical state. In this hypothesis, the secondary of 1991VH was previously in a classical 1:1 spin–orbit resonance with an orbit period likely between 28 and 35 hr before being perturbed by an Earth encounter within ∼80,000 km. We find that if the energy dissipation within the secondary is relatively inefficient, this excited dynamical state could persist to today and produce the observed ground-based measurements. Coupled with the orbital history of 1991VH, we can then place a constraint on the tidal dissipation parameters of the secondary.

Chemically reactive flow of mircopolar Eyring–Powell Ferrofluid passes through stretching surface

In this investigation, the behavior of a chemically reactive flow of micropolar Eyring–Powell ferrofluids over stretchable surface was examined. The study also considers heterogeneous and homogeneous chemical reactions, as well as thermal radiation and magnetic dipole impacts. By applying suitable similarity variables, the nonlinear partial differential governing equations, which describe the flow and energy dynamics of the micropolar fluid, were transformed into ordinary differential equations. The resultant equations were then numerically solved by using the shooting method with a Runge–Kutta update. The model equations are presented and discussed in dimensionless form through numerical approximations. A variety of numerical tests were performed for the dimensionless parameters to provide a comprehensive understanding. The MATLAB version 2023 was used for the numerical computations as well as graphical illustrations. It was concluded that the velocity field decreases with greater values of the ferro-magnetic parameter ß as well as for other fluid material parameters H, and ß. Whereas the temperature field increases by increasing the thermal radiation R while decreases with a higher dissipation parameter λ1 and Prandtl number Pr. The numerical simulation for these parameters were shown graphically, and the values were tabulated for clear illustration. Moreover, the current work was also compared with the findings of existing studies from recent literature to validate and contextualize the findings.

Ultrasonic wave diffusion-based investigations on microstructural development in multi-scale cementitious materials

Microstructural study of cement and its composites has immense significance from both fundamental and applied research points of view. Concrete, a mesoscale cementitious material, possesses high heterogeneity and inherent complex behavior. The multi-phases of concrete show an evolving nature at any instance of time, starting from the initiation of hydration to the complete maturity level. The hydration products and the aggregate-matrix Interfacial Transition Zone (ITZ) play a crucial role in defining the microstructural arrangement, which determines the mechanical and durability properties. Ultrasonic diffusion-based study has a unique advantage for characterising microstructural behavior in heterogeneous materials as it can decouple the different attenuating parameters- diffusivity (D) and dissipation (σ), where, D reflects the material microstructure and σ indicates the viscoelastic property of the base material. For that purpose, an ultrasonic diffusion study has been carried out in the present research for hydration monitoring in two scales, cement (micro-scale), and concrete (meso-scale) under different transmission modes. Ultrasonic measurements have been processed in the time-frequency domain to deduce the diffusivity and dissipation parameters using Spectral Energy Density distribution over the entire time window. The present research reveals the key findings as follows: (1) the influence of microstructure in ultrasonic wave propagation can be explicitly demonstrated using diffusion based analytical formulation and experimental results; (2) ultrasonic parameters (in terms of diffusivity and dissipation) can provide physical information on microstructural development in cementitious material during its hydration stage; and (3) the diffusion based method can distinguish the complex microstructural behavior across the scales of heterogeneity- micro-scale (cement paste) to meso-scale (concrete).

Multiple current reversals in driven inertial coupled Brownian particles under rough symmetric periodic potential

Multiple current reversals, where the direction of the net current changes multiple times with the external load, is an anomalous transport property of a driven inertial Brownian particle under periodic potential. Here, we investigated inertial coupled Brownian particles under rough symmetric periodic potential driven by external periodic force to uncover that small microscopic spatial heterogeneity leads to multiple current reversals under weak inter particle coupling. We showed that the current reversals do not exist without the roughness in the potential and coupling of the particles. Although the multiple current reversals persists in a wide range of noise strengths, however, it is sensitive to dissipation constant and parameters of the external driving force. The collective dynamics of the coupled particles becomes asynchronous in presence of roughness and may be responsible for the anomalous behavior. Our calculations underscore a nontrivial role of microscopic spatial heterogeneity of the periodic potential in the transport properties of coupled Brownian particles.

Integrating the complex rheological Carreau model with the Graetz-Brinkman problem in a horizontal passage

ABSTRACT The current investigation emphasizes the influence of viscous dissipation in laminar forced convection internal flow for horizontal conduit using the non-Newtonian fluid. A Carreau fluid model is taken into account. The hydrodynamically developed velocity profile is obtained by employing a perturbation approach. A classical Graetz approach is utilized to achieve the solution of the developed energy equation while the MATLAB built-in command bvp4c is taken into account for the solution of the Eigenvalue problem. The negligible axial conduction and uniform physical characteristics are presumed. The influence of the viscous dissipation and model parameters on non-dimensional bulk temperature and Nusselt number is deliberated for both cooling and heating situations. The current analysis is valid for small values of Weissenberg number We ≤ 1 . The findings reveal that viscous dissipation has a significant impact on temperature distribution in both developing and fully established regions.

Suction influence on magneto-convective fluid flow embedded in a permeable media under internal friction

This work examines the natural convection flow of an incompressible, viscous, and electrically conducting fluid down a vertical flat plate in the presence of conduction, as well as the effects of suction, magnetic field, viscous dissipation, porous medium, and heat generation. The governing momentum and energy equations have numerical solutions. The impacts of suction, heat production, magnetic, porosity, and viscous dissipation parameters on two-dimensional flow are discussed. Graphical representations of the velocity profile, temperature distribution, skin friction, rate of heat transfer, and surface temperature distribution are shown. The presence of porous media and improving suction values improves the friction drag but diminishes the energy transfer. The thermal production parameter raises the energy inside the flow but diminishes the heat transfer coefficient. This work attempts to offer important insights into these intricate processes by examining the effects of controlling factors including magnetic fields, porous medium, and suction parameters. This research conclusion may find applications in coolers, heat exchangers, and environmental remediation technologies that are more effective, advancing engineering and sustainable practices.

Joint analysis of JUICE and Europa Clipper tracking data to study the Jovian system ephemerides and dissipative parameters

Context. Jupiter and its moons form a complex dynamical system that includes several coupling dynamics at different frequencies. In particular the Laplace resonance is fundamental to maintaining the energy dissipation that sustain Io’s volcanic activity and Europa’s subsurface ocean; studying its stability is thus crucial for characterizing the potential habitability of these moons. The origin and evolution of the Laplace resonance is driven by the strong tidal interactions between Jupiter and its Galilean moons, and the future planetary exploration missions JUICE and Europa Clipper could bring new light to this unsolved mechanism. During the Jupiter tours of both missions and JUICE’s Ganymede orbital phase, two-way radiometric range and Doppler data will be acquired between Earth ground stations and the spacecraft, which will be processed to recover the static and time-varying gravity field of the moons. Moreover, range and Doppler data will improve the orbit accuracy of the moons, providing precise measurements of Jupiter’s tidal parameters. Aims. This work presents a covariance analysis of the joint orbit determination of JUICE and Europa Clipper, aimed at quantifying the expected uncertainties on the main parameters that characterize the dynamics of the Jupiter system. Methods. We simulated radio science data from JUICE and Clipper missions under conservative noise assumptions, using a multi-arc approach to estimate the ephemerides and dissipation in the system. Results. Even though JUICE and Europa Clipper will not perform flybys of Io, the strong coupling with Europa and Ganymede will allow an improvement of our knowledge of the Jupiter-Io dissipation parameters thanks to JUICE and Europa Clipper radiometric data. Moreover, the expected uncertainty in Jupiter’s dissipation at the frequency of Callisto could unveil a potential resonance locking mechanism between Jupiter and Callisto.

Quad-functioning parity layout for nanocomputing: A QCA design

Quantum dot cellular automata (QCA) is considered an alternative to conventional technologies like CMOS (Complementary Metal-Oxide-Semiconductor) technology due to its potential for lower power consumption, higher speed, and increased device density. QCA introduces a novel approach to designing nano communication circuits and systems. Nano communications data mistakes are detected via parity generators and checkers. The parity bit of each data block ensures that the number of 1′s is either even or odd. Consequently, the system requires four circuits: an even parity generator, an odd parity generator, an even parity checker, and an odd parity checker. The whole system requires more space and cell complexity. In this work, we propose a QCA architecture that serves as a generator for both even and odd parities, as well as a checker for both even and odd parities. It is a quad-functioning circuit that performs four distinct operations within a single design, utilizing 118 QCA cells and occupying an area of 0.17 μm2. The recommended approach uses an efficient XOR gate, resulting in improvements across several performance metrics. QCAPro calculates energy dissipation and design parameters. The recommended QCA circuit outperformed similar QCA circuits in size, complexity, and energy dissipation. The circuit's design cost functions are also low. There has been a 17% reduction in latency and an 86% improvement in QCA-specific costs when compared to the optimal existing design. Moreover, it necessitates a 40% reduction in majority gate usage. The proposed design may compete effectively with other equivalent higher-order circuit designs by reducing the need for multiple blocks in conventional circuits to execute the same task. This architecture holds potential benefits for nano processors and nano communication networks.

Influence of Magneto-hydrodynamic with Williamson Nanofluid Flow Control of Forcheeimer Model under Chemical Reaction

Objective: The research focused on Williamson's nonlinear governing flow on Magneto hydrodynamic incompressible, steady fluid over a porous stretching sheet in a two-dimensional direction. The permeable stretching sheet embedded by Williamson fluid is based on the flow model of non-Darcy Forchheimer law with chemical reaction. This article concentrated on an energy equation dominated by the dissipation parameter analysis. Methods: The governing mathematical partial derivative formulations are changed to a system of ordinary differential formulations with appropriate similarity transformation. The mathematical formulations are evaluated employing the numerical method of the R-K fourth-order scheme. MATLAB software bvp4c is used for computing numerical results. The numerical results and graphs were successfully demonstrated with the R-K fourth-order system. Findings: For the influence of Williamson non-Newtonian, non-fluid observed emerging dimensionless quantifiers such as Williamson number, porous, electric, thermophoresis, Brownian motion, Prandtl, and Schmidt dimensionless number respectively. The performance of non-dimensional parameters is investigated in detail. Novelty: As described in the results, Williamson's non-Newtonian nanofluid under the influence of magneto-hydrodynamics is mentioned as a new value to the existing literature. The gained results are the innovative study of the influence of chemical reaction on Williamson non-Newtonian nanofluid and magnetic strength and reported on dimensionless parameters. Keywords: Electric parameter, Williamson Nanofluid, Darcy-Forchheimer, Viscous dissipation, Chemical reaction quantifier

Effect of grain orientation distribution on the mechanical properties of Al-7.02Mg-1.78Zn alloys

PurposeDuring the forming process, aluminum alloy sheets develop various types of textures and are subjected to cyclic loading as structural components, resulting in fatigue damage. This study aims to develop polycrystalline models with different orientation distributions and incorporate suitable fatigue indicator parameters to investigate the effect of orientation distribution on the mechanical properties of Al-7.02Mg-1.78Zn alloys under cyclic loading.Design/methodology/approachIn this study, a two-dimensional polycrystalline model with 150 equiaxed grains was constructed based on optical microscope images. Subsequently, six different orientation distributions were assigned to this model. The fatigue indicator parameter of strain energy dissipation is utilized to analyze the stress response and fatigue crack driving force in polycrystalline models with different orientation distributions subjected to cyclic loading.FindingsThe study found that orientation distribution significantly influences fatigue crack initiation. Orientation distributions with a larger average Schmid factor exhibit reduced stress response and lower fatigue indicator parameters. Locations with a larger average Schmid factor experience greater plastic deformation and present a higher risk for fatigue crack initiation. RVE with a single orientation undergoes more rotation to reach cyclic steady state under cyclic loading due to the ease of deformation transfer.Originality/valueCurrently, there are no reports in the literature on the calculation of fatigue crack initiation for Al-Mg-Zn alloys using the crystal plasticity finite element method. This study presents a novel strategy for simulating the response of Al-7.02Mg-1.78Zn materials with different orientation distributions under symmetric strain cyclic loading, providing valuable references for future research.

Exploring Unsteady Three-Dimensional Casson Fluid Flow through a Stretching Surface with Heat Source/Sink: A Numerical Investigation

This research aims to examine the effects of a heat source or sink and viscous dissipation on an MHD unsteady three-dimensional Casson fluid flow across a stretched sheet. Using similarity transformations, the governing partial differential equations are transformed into coupled ordinary differential equations, which are then solved numerically in Matlab. The numerical findings for several physical parameters that impact velocity and temperature profiles are described in tables and graphs. The interesting finding are recorded as follows: When the Magnetic parameter increases, the skin friction coefficient increases along x and z directions, but when the Casson parameter lowers, it decreases. The Nusselt number increases with the enhancement of viscous dissipation parameter and heat source or sink parameter. Understanding the behavior of non-Newtonian fluids in the presence of heat transfer is crucial in a number of domains, including chemical engineering, biomechanics, and material processing. These applications might benefit from this kind of study.

Computational study of micropolar Eyrling-Powell ferrofluid flow

This study investigates the behavior of micropolar Eyring-Powell ferrofluids over a stretchable surface, considering heterogeneous-homogeneous chemical reactions, thermal radiation, and magnetic dipole effects. The governing partial differential equations are transformed into ordinary differential equations (ODEs) using similarity transformations, which are then solved using the shooting method with Runge-Kutta updates. The effects of various parameters on the flow and temperature fields are computed and visualized using MATLAB 2023. The results show that the velocity field decreases with increasing ferro-magnetic parameter β and fluid material parameter ß, while the temperature field increases with thermal radiation R, but decreases with higher dissipation parameter λ 1 and Prandtl number Pr. The results are in excellent agreement with previously published data, validating the accuracy of our approach.

Uncovering dominant mechanisms of nano-mechanical properties of AlTaO4 ceramics from structural characteristics

This investigation comprehensively examines the nano-mechanical properties of AlTaO4 for the first time, including Young's modulus (E), hardness (H), and fracture toughness (KIC). Variability in the regional distribution of E and H within AlTaO4 is elucidated through an examination spanning both the grain and bulk material scales, and offers a correlational equation of E and H from fit statistical outcomes. Additionally, the H/E ratio and micro-hardness dissipation parameter of AlTaO4 reach 0.063 and 0.61, respectively, which demonstrate its exceptional wear resistance. Further investigation emphasizes that the distinctive crystalline structure, short bond lengths, high bond strength, and elevated charge density around aluminum ions significantly contribute to the high E (208 GPa) and H (13.1 GPa) of AlTaO4. The capacity for energy absorption during elastic deformation enhances crack formation energy and contributes to the relatively high fracture toughness (2.6 MPa m1/2) of AlTaO4. This work elucidates the excellent mechanical properties of AlTaO4 by applying nanoindentation and first-principle calculation, which will advance the applications of AlTaO4 as high-temperature materials.

METHOD OF ASSESSING THE CHANGE IN DESIGN PARAMETERS OF PRECISION ROTARY SYSTEMS BY THE PHASE SHIFT OF THE VIBRATION STATE

The article examines the issue of precision rotary systems (PRS) and the relationship between their dissipative characteristics and changes in design parameters, which is applicable for assessing the quality of their assembly and diagnosing objects in general. We identified a dynamic model, the dissipative parameters of which sufficiently accurately reflect the local properties of the structure. The question of assessing the quality of assembly by dissipative parameters comes down to the choice of the diagnostic sign that is most suitable for this case and the method of its measurement. Such a sign is a phase shift between the disturbance force and the vibration velocity. From this point of view, phase-frequency measurement methods are generally more accurate, which allows using the advantages of precise hardware methods to obtain information to the fullest extent. The proposed variation ratio, which connects the changes in a real object’s phase vector of the mechanical impedance (PVMI) and the deviation of the dissipative parameters of its mathematical model, makes it possible to diagnose the dissipative parameters with a sufficient accuracy degree. The considered numerical example of a partial assembly of precision rotary systems confirms the accuracy of the calculation. Thus, the proposed variation ratio, which connects the changes in the PVMI of a real object and the deviation of the dissipative parameters of its mathematical model, allows for the diagnosis of the dissipative parameters with a sufficient accuracy degree. The considered numerical example of a partial assembly of the PRS confirms the accuracy of the calculation. This fact is of particular importance in manufacturing aviation and space technology products. We should also note that the existing analysis methods do not provide an opportunity to form an idea about the nature of the total measured signal and its structure. Therefore, the work solves the task of developing a method for diagnosing the controlled technical condition of a rotary electromechanical system based on the selection of the most informative ranges of the output signal to increase the reliability of diagnosis. Keywords: oscillatory system, dissipative properties, mathematical model, phase angle, impedance, sensitivity matrix.

METHOD OF ASSESSING THE CHANGE IN DESIGN PARAMETERS OF PRECISION ROTARY SYSTEMS BY THE PHASE SHIFT OF THE VIBRATION STATE

The article examines the issue of precision rotary systems (PRS) and the relationship between their dissipative characteristics and changes in design parameters, which is applicable for assessing the quality of their assembly and diagnosing objects in general. We identified a dynamic model, the dissipative parameters of which sufficiently accurately reflect the local properties of the structure. The question of assessing the quality of assembly by dissipative parameters comes down to the choice of the diagnostic sign that is most suitable for this case and the method of its measurement. Such a sign is a phase shift between the disturbance force and the vibration velocity. From this point of view, phase-frequency measurement methods are generally more accurate, which allows using the advantages of precise hardware methods to obtain information to the fullest extent. The proposed variation ratio, which connects the changes in a real object’s phase vector of the mechanical impedance (PVMI) and the deviation of the dissipative parameters of its mathematical model, makes it possible to diagnose the dissipative parameters with a sufficient accuracy degree. The considered numerical example of a partial assembly of precision rotary systems confirms the accuracy of the calculation. Thus, the proposed variation ratio, which connects the changes in the PVMI of a real object and the deviation of the dissipative parameters of its mathematical model, allows for the diagnosis of the dissipative parameters with a sufficient accuracy degree. The considered numerical example of a partial assembly of the PRS confirms the accuracy of the calculation. This fact is of particular importance in manufacturing aviation and space technology products. We should also note that the existing analysis methods do not provide an opportunity to form an idea about the nature of the total measured signal and its structure. Therefore, the work solves the task of developing a method for diagnosing the controlled technical condition of a rotary electromechanical system based on the selection of the most informative ranges of the output signal to increase the reliability of diagnosis. Keywords: oscillatory system, dissipative properties, mathematical model, phase angle, impedance, sensitivity matrix.