Open Access

Article

Article ID: 2529

Multi-objective Thermal Exchange Optimization algorithm applied to mechanical system design

by Fran S. Lobato, Fabian A. Lara-Molina

Mechanical Engineering Advances, Vol.3, No.3, 2025;

Engineering system design is a highly relevant and dynamic field, with numerous applications reported in the literature. This type of problem generally encompasses several objectives and constraints, including those arising from mass, energy, and momentum balances, material behavior equations, and a range of environmental, physical, and operational restrictions. To address such challenges, a range of evolutionary optimization strategies has been proposed and evaluated. This work presents a Multi-objective Thermal Exchange Optimization (MTEO) algorithm that integrates concepts of Pareto dominance along with crowding distance strategies. To assess its performance, the proposed algorithm is applied to three well-established mechanical design problems. The results demonstrate that the MTEO algorithm provides accurate approximations of the Pareto front in comparison with conventional evolutionary methods. Specifically, average reductions of approximately 36%, 32%, and 68% were observed for the respective design problems. Furthermore, the MTEO parameters were found to be easy to configure across all applications.

Open Access

Article

Article ID: 2587

Optimization of mirror mount design based on opto-mechanical performance for space applications

by Fatouma Maamar

Mechanical Engineering Advances, Vol.3, No.3, 2025;

A new fixation type for mirror assembly was proposed in space telescope. The optomechanical design of a large aperture is necessary to maintain the stability of the optical structure regarding environmental disturbances, restrictions on the weight, size and shape of the mirror, which must be satisfied for space applications. This paper presents a study focusing on the optimal optomechanical design for mirror mounting using glue pad bonding. We have developed a new design specifically tailored for the BK-7 mirror with a diameter of 500 mm and a thickness of 45 mm. The primary aim of this research is to determine the optimal combination of glue pad number, size, and thickness to minimize both glue stress and errors in the mirror’s shape. To achieve this, we conduct simulations under various load cases, varying the size and thickness of the glue pads. The new design results demonstrate the effectiveness of the proposed optimization method, which greatly minimizes thermal stress in the mirror and ensures adequate supporting stiffness. This solution for the mirror and mount design can provide valuable support to decision-makers and optical engineers during the development phase of space optomechanical systems.

Open Access

Article

Article ID: 2838

Innovative semi-analytical approaches to micropolar MHD fluid flow between stretching disks under radiant heat flux

by Ali Ahmadi Azar

Mechanical Engineering Advances, Vol.3, No.2, 2025;

This study investigates the viscous, incompressible, laminar, time-independent micropolar MHD fluid flow between two stretching disks under radiant heat flux, with applications in industrial systems like turbines and nuclear reactors. Using suitable similarity transformations, the nonlinear constitutive equations are reduced to coupled ODEs and solved through two novel semi-analytical approaches: the Hybrid Analytical-Numerical method (HAN method), which constructs analytical solutions from numerical data, and the modified Akbari-Ganji Method (modified AGM) that operates independently of numerical solutions. Results demonstrate that stretching Reynolds number, magnetic parameter, and three micropolar parameters significantly affect all five dimensionless quantities (axial/radial velocity, microrotation, temperature, and concentration), while Eckert number variations cause a 16.5% maximum temperature increase when doubled from 1 to 2. A 429% temperature surge occurs as the Prandtl number rises from 3 to 22, whereas the Schmidt number (0.1–1.5) only modifies the concentration profile shape without changing extrema. The radiation parameter (0–8) alters temperature distribution between disks without affecting maxima/minima. Three validation methods confirm solution accuracy: graphical verification, comparison with existing analytical results, and cross-method consistency between HAN and modified AGM outputs. The study’s innovative dual-method approach coupled with 3D contour visualizations provides unprecedented semi-analytical solutions for this classical problem, offering both theoretical advancement and practical industrial insights.

Open Access

Article

Article ID: 2512

On the analytical mechanics methods in mathematical modeling the dynamics systems with geometric constraints

by Aleksandr Ya Krasinskiy

Mechanical Engineering Advances, Vol.3, No.2, 2025;

A necessary condition for the most effective application of the mathematical control theory results to the modern automatic devices dynamics сonsideration is the presence of an adequate nonlinear mathematical model obtained by strict general methods. Methods for reducing the dimensions of dynamic models of systems with geometric constraints by analytical mechanics methods for non-free systems are considered due to the transition to equations in redundant coordinates free of constraint multipliers. A detailed algorithm for this procedure and its justification is given. Using the theory of critical cases, a complete solution is given to the stabilizing problem of a given configuration of systems with geometric constraints.

Open Access

Article

Article ID: 2878

Semi-analytical solution for nonlinear Von Kármán swirling fluid flow via the hybrid analytical and numerical method

by Ali Ahmadi Azar

Mechanical Engineering Advances, Vol.3, No.2, 2025;

This study investigates the nonlinear and classical problem of Von Kármán’s viscous swirling fluid flow caused by a single rotating disk. Despite over a century since this problem was first introduced, recent advancements enable more accurate calculations and practical results than previously possible. The core innovation of this paper lies in the application of the Hybrid Analytical and Numerical method (HAN method), which facilitates the derivation of a semi-analytical solution to complex nonlinear differential equations. The HAN method combines numerical and analytical approaches to solve nonlinear problems. Initially, the system of nonlinear differential equations is solved using an arbitrary numerical method. The numerical solution then aids in extracting the analytical solution, which can take forms such as polynomial solutions with constant and unknown coefficients. Since boundary conditions lack the capacity to generate a sufficient number of algebraic equations, the numerical solution provides the additional required equations. The flexibility of the HAN method stems from its ability to leverage various numerical methods, making it a robust approach for solving nonlinear differential equations. Using this methodology, the Von Kármán problem is analytically calculated with remarkable accuracy. Furthermore, this study provides highly precise calculations of several physical and practical outputs, including the thickness of the layer, the slope of flow lines at the wall in the peripheral direction, the peripheral component of wall shear stress, the moment on one side of the wetted disk, the dimensionless moment coefficient for both sides of the disk, Reynolds number as a function of the disk’s finite radius, volume flux, and mechanical power. This research contributes to two main perspectives: first, the mathematical aspect, which demonstrates the ability of the HAN method to solve various nonlinear problems; second, the practical-physical perspective, showcasing the enhanced accuracy and reliability of the obtained results in analyzing fluid flow mechanics.

Open Access

Article

Article ID: 2052

Two-phase heat conductors for passive thermal regulation systems of electric vehicles

by Leonard Vasiliev, Alexander Zhuravlyov, Dmitry Sadchenko

Mechanical Engineering Advances, Vol.3, No.2, 2025;

Due to the growing demands for a better environment, great efforts are currently being made in the world to create and improve electric and hybrid vehicles. Heat-loaded equipment of electric transport requires efficient cooling systems. A loop thermosyphon made of aluminum, having two flat multi-channel evaporators and one condenser for cooling electronic components, is developed and tested with acetone as the working fluid. The procedure and results of an experimental study of the characteristics of a thermosyphon are described. The evaporators are supplied with a heat load of varying power; the absorbed heat is dissipated by the condenser. The working fluid is acetone. The influence of thermal load and volume of working fluid on the thermal resistance of a thermosyphon and its components was determined and investigated. The lowest evaporator thermal resistance is 0.15 K/W for the heat load range 30–60 W. The thermosyphon operates stably in a wide range of thermal loads and quickly responds to their changes.