- Role of Thumb of Mechanical Engineering, Engineering, Mathematics, Physics, Technology, Civil Engineering, and 9 moreDesign, Mechanical Engineering, Renewable Energy, Artificial Intelligence, Materials Engineering, Materials Science, Heat Transfer, Computational Fluid Dynamics, and Fluid Mechanicsedit
- The Journal of Computational Applied Mechanics (JCAMECH) is an international research journal, which publishes top-le... moreThe Journal of Computational Applied Mechanics (JCAMECH) is an international research journal, which publishes top-level scientific works. The journal aims to promote the international exchange of new knowledge and recent development information in all aspects of computational and applied mechanics. Manuscripts must be submitted only in English and should be written according to sound grammar and proper terminology.
The Journal of Computational Applied Mechanics is a fully open access, double-blind peer-reviewed, electronic and print, quarterly publication concerned with appropriate aspects of Mechanical Engineering. JCAMECH publishes original research papers, review papers, case reports, technical notes, and short communications. The JCAMECH has institutional support from the University of Tehran and there are no charges either for the article processing or the article submission.
The subject areas include, but are not limited to the following fields:
Biomechanics
Dynamics
Continuum Mechanics
Computational Mechanics
Solid and Fluid Mechanics
Heat Transfer
Vehicle System Dynamics
Hydromechanics
Design and Drafting
Finite Element Analysis
Heating and Cooling Systems
Kinematics
Aerodynamics
Mechanical Engineering Technology
Mechanical Systems
Mechanics
Nano and Micro-Mechanics
Mechatronics, Control, and Robotics
MEMS and NEMS
Structural Analysis
Thermodynamics and Thermo-scienceedit - Prof. Abbas Rastgooedit
In this paper, a thermo-elastic analysis is presented to obtain stresses, displacements, and the thermal field in the axisymmetric clamped-clamped rotating thick cylindrical shell with nonlinear variable thickness. This shell is subjected... more
In this paper, a thermo-elastic analysis is presented to obtain stresses, displacements, and the thermal field in the axisymmetric clamped-clamped rotating thick cylindrical shell with nonlinear variable thickness. This shell is subjected to mechanical and thermal load in two dimensions. The governing equations are formulated as a set of non-homogeneous ordinary differential equations with variable coefficients. The system of partial differential equations is semi-analytically solved by using (MLM). The solution of equations is obtained by applying boundary conditions and ensuring continuity between the layers. The problem is also solved, using the finite element method (FEM). The obtained results of the disk form multi-layers method (MLM) are compared with those of FEM.
Research Interests:
Friction Stir Welding (FSW) has revolutionized modern manufacturing with its advantages, such as minimal heat-affected zones and improved material properties. Accurate torque prediction in FSW is crucial for weld quality, process... more
Friction Stir Welding (FSW) has revolutionized modern manufacturing with its advantages, such as minimal heat-affected zones and improved material properties. Accurate torque prediction in FSW is crucial for weld quality, process efficiency, and energy conservation. Many researchers achieved models for torque based on experimental research, yet the models were limited to a specific type of material. In recent years, the use of machine learning techniques has increased in industry in general and in welding in particular. In this study, a machine learning model was prepared based on artificial neural networks, and Shapley-Additive Explanations were used to predict the rotational torque from 287 experiments that had been conducted in several previous studies. The achieved model has remarkable predictive performance, with an R-squared of 99.53% and low errors (MAE, MAPE, and RMSE). Moreover, a machine learning polynomial regression was examined for comparisons. A parametric importance analysis revealed that rotational speed, plate thickness, and tilt angle significantly affect torque predictions, while the rest of the variables had minimal importance.
Research Interests:
This research investigates the numerical analysis of magnetohydrodynamic (MHD) mixed convection flow and heat transfer within a bottom lid-driven cavity filled with water-alumina (Al2O3) nanofluid. The cavity's sidewalls exhibit a wavy... more
This research investigates the numerical analysis of magnetohydrodynamic (MHD) mixed convection flow and heat transfer within a bottom lid-driven cavity filled with water-alumina (Al2O3) nanofluid. The cavity's sidewalls exhibit a wavy profile and are maintained at distinct temperatures. Cavity domain exhibit distinct free and force convections. These wavy walls, characterized by zigzag shapes determined by various wave amplitudes and their ratios (wave form), create a dynamic thermal environment. The top and bottom surfaces remain flat and well-insulated, while forced convection is induced by the drag of the bottom wall from left to right at a constant speed. Additionally, the bottom wall is subjected to a vertical magnetic field. The system of equations is discretized using the finite difference method. The numerical solutions are derived by the Gauss-Seidel iterative method. The study primarily focuses on investigating the effects of key parameters, including the wavy wall geometry, solid volume fraction (0 ≤ φ ≤ 0.0003), Rayleigh number (103≤ Ra ≤105), and Hartmann number (0 ≤ Ha ≤0.6). Numerical solutions are computed across different ranges of these parameters, and the obtained results are successfully validated against previous numerical studies. The findings reveal that higher Hartmann numbers and solid volume fractions lead to lower circulation rates and Nusselt numbers. Convection is markedly enhanced with higher amplitude and its ratios of the wavy sidewalls. The combined two-sinusoidal function with the wave amplitudes of 2.5 and 0.47 of provides the highest mean Nusselt numberof3.204 with the highest dimensionless stream function of 1.638. These results highlight the significant influence of the wave form on both flow and temperature distributions.
Research Interests: Partial Differential Equations, Numerical Methods, Applied Numerical Methods in Engineering, Computational Fluid Dynamics (CFD) modelling and simulation, CFD Analysis, and 3 moreCFD and numerical grid generation, Computational Fluids Dynamics (CFD), and Numerical and Experimental Methods in Fluid Dynamics
Hybrid nanofluid's applications are diverse and encompass fields such as chemical engineering, microelectronics, solar energy, cooling systems, electronics, and power-saving technologies, where their enhanced heat transfer properties... more
Hybrid nanofluid's applications are diverse and encompass fields such as chemical engineering, microelectronics, solar energy, cooling systems, electronics, and power-saving technologies, where their enhanced heat transfer properties offer significant advantages. In this study, a threedimensional Maxwell hybrid nanofluid under MHD effects is analyzed and shown across a stretched sheet. Molybdenum disulfide (MoS2) and graphene oxide (GO) nanoparticles combined with ethylene glycol (EG) make up the hybrid nanofluid. Coupled nonlinear partial differential equations are used to describe the controlling equations. These equations are then converted into coupled nonlinear ordinary differential equations using similarity transformations. Through the use of MATLAB programming and the bvp4c technique, these equations may be solved numerically. Figures and tables that illustrate the effects of the Deborah number, magnetic parameter, rotational parameter, and volume percentage of nanoparticles on temperature, velocity, skin friction coefficient, and Nusselt number have been studied. The salient characteristics are: The velocity decreases with increasing Deborah number, magnetic parameter, and rotational parameter values. The findings indicate that the surface temperature is increased by higher values of the Deborah number, magnetic parameter, and rotational parameter. The hybrid nanofluid exhibits greater values of temperature, velocity, and Nusselt number in comparison to the nanofluid. A comparison analysis agrees well with the previous studies.
Research Interests:
This study attempts to shed light on the analysis of the static behavior of simply supported FG type property gradient material beams according to an original refined 2D shear deformation theory. Young's modulus is considered to vary... more
This study attempts to shed light on the analysis of the static behavior of simply supported FG type property gradient material beams according to an original refined 2D shear deformation theory. Young's modulus is considered to vary gradually and continuously according to a power-law distribution in terms of volume fractions of the constituent materials. The equilibrium equations are obtained by applying the principle of virtual work. The governing equilibrium equations obtained are thus solved by using the analytical model developed here and Navier's solution technique for the case of a simply supported sandwich beam. Moreover, Using the numerical results of the non-dimensional stresses and displacements are calculated and compared with those obtained by other theories. Two studies are presented, comparative and parametric, the objective of which is the first to show the accuracy and efficiency of the theory used and the second to analyze the mechanical behavior of the different types of beams under the effect of different parameters. Namely boundary conditions, the material index , the thickness ratio and the type of beam.
Research Interests:
The research article investigates the behavior of a functionally graded semiconducting rod with internal heat source of length l under the thermal shock. A sudden heat source is applied to the left boundary of the finite rod. The... more
The research article investigates the behavior of a functionally graded semiconducting rod with internal heat source of length l under the thermal shock. A sudden heat source is applied to the left boundary of the finite rod. The equations of motion are solved analytically and the analytical expressions of displacement, carrier density, temperature distribution and stresses are obtained. The numerical values of these expressions are calculated and presented graphically to show the effect of non-homogeneity parameter on the components. The variations of the parameters are shown for different theories of thermoelasticity namely Modified Green-Lindsay(MGL) theory, Green-Lindsay(GL) theory, Lord-Shulman(LS) theory and Coupled(CT) theory.
Research Interests:
In recent years, electrical appliances have become an integral part of human life, and efforts have been made to improve the quality and durability of electrical boards. One of the ways to improve the life of electrical boards is using... more
In recent years, electrical appliances have become an integral part of human life, and efforts have been made to improve the quality and durability of electrical boards. One of the ways to improve the life of electrical boards is using cooling methods suitable for transferring the heat generated by the boards. In this paper, three different models of Case 1, Case 2, and Case 3 have been analyzed to provide an optimal model with the highest average Nusselt number. To achieve the optimal model the effect of heat source, the characteristics of hot and cold barriers and their locations on the flow field, heat transfer between two horizontal concentric cylinders with the presence of nanofluids were investigated. The results have shown that for all volume fractions, the Nusselt number increases with rising Riley number, as well as for the inner and outer cylinder, the value of the average Nusselt number increases at a constant Riley number with rising the volume fraction from 0 to 0.8%. Therefore, the highest Nusselt number occurs in volume fraction of 0.8% and Riley number of 10 5 .
Research Interests:
This paper presents size dependent stability analysis a cantilever micro laminated beam embedded in elastic medium by using the modified coupled stress theory which includes the length scale parameter. The micro beam subjected to... more
This paper presents size dependent stability analysis a cantilever micro laminated beam embedded in elastic medium by using the modified coupled stress theory which includes the length scale parameter. The micro beam subjected to compressive load is considered as three composite laminas and embedded in elastic medium which is modelled in the Winkler foundation model. In the obtaining of the governing equations, the energy principle is used. In the solution of the buckling problem, the energy based Ritz method is implemented with algebraic polynomials. In order to accuracy obtained expressions and used method, a comparative study is performed. Many parametric studies are presented in order to investigate the buckling of laminated micro beams. For this purpose, effects of stacking sequence of laminas, geometric parameters, length scale parameter, fiber orientation angle, the parameter of elastic medium on critical buckling loads of laminated micro beams are investigated.
Research Interests:
The wire drawing process is an essential technique in mechanical and industrial operations in lots of applications. Therefore, the current article aims to employ different methodologies (i.e., experimental, numerical) to investigate the... more
The wire drawing process is an essential technique in mechanical and industrial operations in lots of applications. Therefore, the current article aims to employ different methodologies (i.e., experimental, numerical) to investigate the optimum operating conditions and lubrication type on the surface and mechanical quality of these wires. By examining the effects of die angle, drawing speed, and lubricant type on wire drawing outcomes, the research not only provides valuable insights into process optimization but also contributes to reducing defects and enhancing wire properties. Results demonstrate significant variations in tensile strength based on these parameters, highlighting the need for precise control over process variables to achieve desired outcomes consistently. Moreover, statistical analyses reveal substantial relationships between process variables and tensile strength, offering a deeper understanding of the underlying mechanisms driving wire drawing performance. Overall, this research not only advances the understanding of wire drawing processes but also offers practical insights for improving wire manufacturing techniques, ultimately bolstering product quality, reducing costs, and increasing competitiveness in the global market.
Research Interests:
The tidal wave in the Qiantang River, Hangzhou City, China is quite different from that of KdV equation, it is a shock-like wave with a finite amplitude. This phenomenon has mathematicians adjusting their solitary wave models on how such... more
The tidal wave in the Qiantang River, Hangzhou City, China is quite different from that of KdV equation, it is a shock-like wave with a finite amplitude. This phenomenon has mathematicians adjusting their solitary wave models on how such waves behave. This paper applies the variational theory to insight into the energy behave of the tidal wave, which can be modelled by the Benny-Luke equation, and the exp-function method is used to figure out the solution structure. This paper provides a new window for designing energy harvesting devices from the shock-like waves.
Research Interests:
Sandwich structures are widely used in many industries such as marine& submarine, aerospace, automobiles and etc due to its lightweight nature, high bending stiffness, high fatigue resistance and ability to absorb energy. However, the... more
Sandwich structures are widely used in many industries such as marine& submarine, aerospace, automobiles and etc due to its lightweight nature, high bending stiffness, high fatigue resistance and ability to absorb energy. However, the investigations into sandwich structures with 3D printed core are limited in number. These structures can create a meta material behavior with the change of geometry which leads to negative poison ratio of core. Hence, in this article, investigations into sandwich structures with 3D printed core under various loading for comparing their structural responses have been reviewed in detail. Different shapes of 3D printed cores have been reviewed and their specifications are discussed.
Research Interests: Partial Differential Equations, Computational Mechanics, Structural Dynamic Response Optimization, Numerical Methods, Applied Numerical Methods in Engineering, and 5 moreNonlinear Partial Differential Equations, Computational Solid Mechanics, Energy absorption, Sandwich Structures, and Numerical and Experimental Methods in Fluid Dynamics
The existence of friendly programming environments, which allow the transposition of models developed for different mechanical systems into numerical procedures, easy to access, make it necessary to develop models of mechanical systems... more
The existence of friendly programming environments, which allow the transposition of models developed for different mechanical systems into numerical procedures, easy to access, make it necessary to develop models of mechanical systems used in industry. In this work, we propose to do this for an internal combustion engine. The offered model allows the unitary solution of problems of this type, which involves the calculation of the forces appearing in the engine elements. It offers the possibility to analyze different constructive types of engines. The model is a complex model that finally provides the forces existing in different elements of the engine as well as the developed engine torque.
Research Interests:
This study focuses on the analysis of the bio-thermoelasticity response exhibited by biological tissues when their inner and outer surfaces are free from stress and exposing the outer surface of the skin to harmonic heating with... more
This study focuses on the analysis of the bio-thermoelasticity response exhibited by biological tissues when their inner and outer surfaces are free from stress and exposing the outer surface of the skin to harmonic heating with heatlessness of the inner surface of the skin. The investigation employs a refined Green–Lindsay model for a comprehensive understanding of the phenomenon. A system of partial differential equations is written and the solution is obtained using the Laplace transform and numerical inverse Laplace. The current model's results for temperature, displacement, stress, and strain distributions are presented, and it is compared to various (coupled and uncoupled) models from previous literature. The relaxation times effect on the model with other models is clarified, the effect of time, and some vital parameters are also studied, and tabularly to illustrate the effect of blood perfusion on the four distributions.
Research Interests:
Today the micro electromechanical systems industry is widely developed. This article aims to study static pull-in instability of a clamped micro-switch which is exerted by an electric potential difference in presence of a longitudinal... more
Today the micro electromechanical systems industry is widely developed. This article aims to study static pull-in instability of a clamped micro-switch which is exerted by an electric potential difference in presence of a longitudinal magnetic field. The size dependent nonlocal couple stress theory in framework of Bernoulli-Euler beam hypothesis is utilized to model a clamped micro-switch. The equilibrium equation of micro-beam in micro-switch is derived using the principle of virtual work. To obtain the dimensionless pull-in voltage of micro-switch, the equilibrium equation is solved by Galerkin method. The effect of longitudinal magnetic field and some geometric parameter of micro-beam on the pull-in voltage is studied, taking into account the effects of a set of size dependent factors with and without considering the fringing field. The results from developed model are validated by comparing them with benchmark results.
Research Interests: Partial Differential Equations, Computational Mechanics, Magnetic Field Effects, Differential Equations, Magnetic field, and 5 moreComputational Structural Mechanics, Computational Solid Mechanics, Computational Biomechanics and Unconventional Numerical Methods for Solving Partial Differential Equations Such as Meshfree Methods, Partition of Unity Methods and Isogeometric Analysis., Nonlinear Partial Differential Equations, Couple Stress, and Galerkin Method
Curved beams are widely used in combination with the linear elements of various civil engineering structures. Many researchers attempted to analyze beam curved in plan, beam curved in elevation, and spatial curved beam using different... more
Curved beams are widely used in combination with the linear elements of various civil engineering structures. Many researchers attempted to analyze beam curved in plan, beam curved in elevation, and spatial curved beam using different methods and different approaches and presented analytical exact solution and approximate numerical solution. The analytical exact integration of the governing differential equations is the major difficulty for the analysis of the geometrically non-linear curved beams. To overcome this difficulty, a finite displacement transfer method is proposed to eliminate analytical differentiation and integration, completely. This paper deals with the stiffness matrix of 3D curved beam with varying curvature and varying cross-sectional area. A novel finite displacement transfer method is used to determine displacements of the freely supported node of the cantilever 3D curved beam. The flexibility matrix is derived using the finite displacement transfer method. The stiffness matrix is derived by employing equilibrium and transformation matrix. The finite difference method is used for the numerical solution of the differential equations. Results of the calculation method are compared with the results of other methods in the literature and the FEM based analysis software. For the circular helix with uniformly varying cross-sectional area and 3600 elements, the maximum and minimum percentage difference in the stiffness coefficient is 2.89% and −0.65% respectively. For the elliptic helix with the uniform cross-sectional area and 720 elements, the maximum and minimum percentage difference in the stiffness coefficient is 2.69% and −2.65% respectively. The novel of this study lies in the generation of the stiffness matrix of the 3D curved beams without tedious analytical differentiation and integration of governing equations. The stiffness matrix of the spatial curved beam is applicable to the planer curved beam also.
Research Interests:
Due to the alarming increase in greenhouse gases, switching to clean, renewable energy sources like wind energy has become imperative. As a result, the use of different wind turbines to generate electricity increased worldwide. Meanwhile,... more
Due to the alarming increase in greenhouse gases, switching to clean, renewable energy sources like wind energy has become imperative. As a result, the use of different wind turbines to generate electricity increased worldwide. Meanwhile, Darrieus vertical axis wind turbines (VAWTs) have gained considerable popularity due to their acceptable efficiency. Individual wind turbines are not efficient enough for widespread use and are only suitable for providing domestic energy; therefore, they should be placed in the form of turbine clusters in wind farms. The wind farm configuration and cluster placement have specific considerations, including the rotors' optimal installation distance and rotational direction. In the present study, the rotors installation distance in an array including a cluster of three Darrieus rotors is investigated, and the CFD and Kriging optimization results ensured that the best installation distance is equal to 1.5 times the diameter (1.5D). Also, the CFD results for the rotor's rotational direction at the installation distance of 1.5D showed that when the lower downstream rotor is counter-rotating the leading rotor and clockwise, the overall efficiency of the cluster increases by 67.1%. Additionally, two V-shaped and rhombic configurations are modeled, and the overall efficiency of each turbine in two different configurations is compared separately with the single turbine. In the optimum case, the overall efficiency of turbine A in the V-shaped configuration of three turbines and the rhombic configuration of 12 turbines improved by 54% and 36%, respectively, compared to the single turbine. The study of the streamlines showed that the main reason for improving the performance in the V-shaped configuration is the favorable velocity gradient around the blade, and the decrease in overall efficiency in the V-shaped and rhomboid configurations is wake flow intensity and trapping between the rotors which cause the stagnation zone.
Research Interests: Partial Differential Equations, Computational Mechanics, Differential Equations, Computational Fluid Dynamics (CFD) modelling and simulation, Computational Solid Mechanics, Computational Biomechanics and Unconventional Numerical Methods for Solving Partial Differential Equations Such as Meshfree Methods, Partition of Unity Methods and Isogeometric Analysis., and 2 moreVertical Axis Wind Turbine (VAWT) and Computational Fluids Dynamics (CFD)
Using the disk-form multi-layer method (MLM), a semi-analytical thermoelastic solution for pressurized rotating thick cylindrical shells with varying thickness is obtained. The first-order shear deformation theory (FSDT) is used for... more
Using the disk-form multi-layer method (MLM), a semi-analytical thermoelastic solution for pressurized rotating thick cylindrical shells with varying thickness is obtained. The first-order shear deformation theory (FSDT) is used for displacement and bi-directional temperature fields. The thick shell is divided into some virtual disks, and then a set of differential equations for constant thickness are obtained for each virtual disk. The general solution of the thick cylindrical shell is obtained, by applying continuity conditions between the virtual disks. The governing equations, which are a system of differential equations with variable coefficients, have been solved with MLM. Finally, some numerical results are presented to study the effects of mechanical and thermal loading, on the mechanical behavior of the thick cylindrical shell.
Research Interests: Partial Differential Equations, Computational Mechanics, Differential Equations, Computational Structural Mechanics, Solid mechanics; Computational Mechanics; Applied mechanics, and 6 moreComputational continuum mechanics, Nonlinear Partial Differential Equations, Computational Solid Mechanics, Computational solid / structural mechanics applied to multi-scale analysis and design of composite materials, Applied and Computational Mechanics, and FSDT
Mechanical systems with structural symmetries present vibration properties that allow the calculation to be easier and the analysis time to decrease. The paper aims to use the properties involved by the symmetries that exist in mechanical... more
Mechanical systems with structural symmetries present vibration properties that allow the calculation to be easier and the analysis time to decrease. The paper aims to use the properties involved by the symmetries that exist in mechanical systems for the analysis of the forced response to vibrations. Thus, the study of the properties of systems with symmetries or with identical parts is expanded. Based on a classic model, the characteristic properties that appear in this case are obtained and the advantages of using these properties are revealed. On an example consisting of a truck equipped with two identical engines, the way of applying these properties in the calculation and the resulting advantages is presented.
Research Interests: Partial Differential Equations, Computational Mechanics, Differential Equations, Finite Element Method (FEM), Computational Structural Mechanics, and 3 moreComputational Solid Mechanics, Computational Biomechanics and Unconventional Numerical Methods for Solving Partial Differential Equations Such as Meshfree Methods, Partition of Unity Methods and Isogeometric Analysis., Nonlinear Partial Differential Equations, and Forced vibration
The analysis of the bending behavior of rotating porous disks with exponential thickness variation consisting of viscoelastic functionally graded material is illustrated. The study of bending in the porous disk was done using the... more
The analysis of the bending behavior of rotating porous disks with exponential thickness variation consisting of viscoelastic functionally graded material is illustrated. The study of bending in the porous disk was done using the first-order shear deformation theory. The porous disk is under the effect of a combination of mechanical stresses and thermal distribution. All material factors for the porous disk change across the thickness as a power law of radius. To solve the mathematical structure by using the semi-analytical technique for displacements in the porous disk, and then to treat the structure model with viscoelastic material by the correspondence principle and Illyushin’s approximation manner. Numerical outcomes including the effect of porosity parameter, inhomogeneity factor, and relaxation time are presented with three different sets of boundary conditions for the solid and hollow disks. A comparison between porous and perfect disk with numerous values of porosity parameters and different inhomogeneity factors have been shown to emphasize the importance of complex mathematical structure in modern engineering mechanical designs.
Research Interests:
Modal and frequency response analysis of the piezoelectric energy harvester utilizing the auxetic booster has been performed in this paper. This harvester has composed of a cantilever, auxetic substrate, and piezoelectric layer. The... more
Modal and frequency response analysis of the piezoelectric energy harvester utilizing the auxetic booster has been performed in this paper. This harvester has composed of a cantilever, auxetic substrate, and piezoelectric layer. The influence of the piezoelectric’s electrical circuit and the harvester’s geometrical properties on the fundamental natural frequency, output voltage, and harvested power of the energy harvester have been investigated. The electrical circuit of this electromechanical system consists of a resistor that influences the energy harvester's output voltage and harvested power. A comprehensive parametric study has been performed to find the optimum resistor of the energy harvester. All the analysis has been performed using the finite element method. Mesh size sensitivity analysis of the models is presented, and the finite element model is verified by previous experimental studies. Furthermore, the effect of this energy harvester's damping ratio on the system's outputs has been investigated. The results show that the system's output alters considerably in different damping ratios, and it is necessary to determine the system's damping ratio of the system. The damping ratio of the auxetic energy harvester has been measured through the experimental investigation. The present study illustrates that harvested power of a trapezoidal auxetic energy harvester in resonant frequency could improve by 260 percent by utilizing the optimum resistor. Also, increasing the auxetic booster's thickness could improve the output voltage and harvested power by 48 percent and 22 percent.