Pub Date : 2023-11-06DOI: 10.24425/AME.2018.125439
K. Ahmad, Shigang Wu, H. Rahman
The central theme of this work was to analyze high aspect ratio structure having structural nonlinearity in low subsonic flow and to model nonlinear stiffness by finite element-modal approach. Total stiffness of high aspect ratio wing can be decomposed to linear and nonlinear stiffnesses. Linear stiffness is modeled by its eigenvalues and eigenvectors, while nonlinear stiffness is calculated by the method of combined Finite Element-Modal approach. The nonlinear modal stiffness is calculated by defining nonlinear static load cases first. The nonlinear stiffness in the present work is modeled in two ways, i.e., based on bending modes only and based on bending and torsion modes both. Doublet lattice method (DLM) is used for dynamic analysis which accounts for the dependency of aerodynamic forces and moments on the frequency content of dynamic motion. Minimum state rational fraction approximation (RFA) of the aerodynamic influence coefficient (AIC) matrix is used to formulate full aeroelastic state-space time domain equation. Time domain dynamics analyses show that structure behavior becomes exponentially growing at speed above the flutter speed when linear stiffness is considered, however, Limit Cycle Oscillations (LCO) is observed when linear stiffness along with nonlinear stiffness, modeled by FE-Modal approach is considered. The amplitude of LCO increases with the increase in the speed. This method is based on cantilevered configuration. Nonlinear static tests are generated while wing root chord is fixed in all degrees of freedom and it needs modification if one requires considering full aircraft. It uses dedicated commercial finite element package in conjunction with commercial aeroelastic package making the method very attractive for quick nonlinear aeroelastic analysis. It is the extension of M.Y. Harmin and J.E. Cooper method in which they used the same equations of motion and modeled geometrical nonlinearity in bending modes only. In the current work, geometrical nonlinearities in bending and in torsion modes have been considered.
{"title":"Limit cycle oscillation prediction based on Finite Element-Modal approach","authors":"K. Ahmad, Shigang Wu, H. Rahman","doi":"10.24425/AME.2018.125439","DOIUrl":"https://doi.org/10.24425/AME.2018.125439","url":null,"abstract":"The central theme of this work was to analyze high aspect ratio structure having structural nonlinearity in low subsonic flow and to model nonlinear stiffness by finite element-modal approach. Total stiffness of high aspect ratio wing can be decomposed to linear and nonlinear stiffnesses. Linear stiffness is modeled by its eigenvalues and eigenvectors, while nonlinear stiffness is calculated by the method of combined Finite Element-Modal approach. The nonlinear modal stiffness is calculated by defining nonlinear static load cases first. The nonlinear stiffness in the present work is modeled in two ways, i.e., based on bending modes only and based on bending and torsion modes both. Doublet lattice method (DLM) is used for dynamic analysis which accounts for the dependency of aerodynamic forces and moments on the frequency content of dynamic motion. Minimum state rational fraction approximation (RFA) of the aerodynamic influence coefficient (AIC) matrix is used to formulate full aeroelastic state-space time domain equation. Time domain dynamics analyses show that structure behavior becomes exponentially growing at speed above the flutter speed when linear stiffness is considered, however, Limit Cycle Oscillations (LCO) is observed when linear stiffness along with nonlinear stiffness, modeled by FE-Modal approach is considered. The amplitude of LCO increases with the increase in the speed. This method is based on cantilevered configuration. Nonlinear static tests are generated while wing root chord is fixed in all degrees of freedom and it needs modification if one requires considering full aircraft. It uses dedicated commercial finite element package in conjunction with commercial aeroelastic package making the method very attractive for quick nonlinear aeroelastic analysis. It is the extension of M.Y. Harmin and J.E. Cooper method in which they used the same equations of motion and modeled geometrical nonlinearity in bending modes only. In the current work, geometrical nonlinearities in bending and in torsion modes have been considered.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68944791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/AME.2020.131689
E. Roux, Y. Tillier, Salim Kraria, P. Bouchard
Material parameters identification by inverse analysis using finite element computations leads to the resolution of complex and time-consuming optimization problems. One way to deal with these complex problems is to use meta-models to limit the number of objective function computations. In this paper, the Efficient Global Optimization (EGO) algorithm is used. The EGO algorithm is applied to specific objective functions , which are representative of material parameters identification issues. Isotropic and anisotropic correlation functions are tested. For anisotropic correlation functions, it leads to a significant reduction of the computation time. Besides, they appear to be a good way to deal with the weak sensitivity of the parameters. In order to decrease the computation time, a parallel strategy is defined. It relies on a virtual enrichment of the meta-model, in order to compute q new objective functions in a parallel environment. Different methods of choosing the qnew objective functions are presented and compared. Speed-up tests show that Kriging Believer (KB) and minimum Constant Liar (CLmin) enrichments are suitable methods for this parallel EGO (EGO-p) algorithm. However, it must be noted that the most interesting speed-ups are observed for a small number of objective functions computed in parallel. Finally, the algorithm is successfully tested on a real parameters identification problem.
{"title":"An efficient parallel global optimization strategy based on Kriging properties suitable for material parameters identification","authors":"E. Roux, Y. Tillier, Salim Kraria, P. Bouchard","doi":"10.24425/AME.2020.131689","DOIUrl":"https://doi.org/10.24425/AME.2020.131689","url":null,"abstract":"Material parameters identification by inverse analysis using finite element computations leads to the resolution of complex and time-consuming optimization problems. One way to deal with these complex problems is to use meta-models to limit the number of objective function computations. In this paper, the Efficient Global Optimization (EGO) algorithm is used. The EGO algorithm is applied to specific objective functions , which are representative of material parameters identification issues. Isotropic and anisotropic correlation functions are tested. For anisotropic correlation functions, it leads to a significant reduction of the computation time. Besides, they appear to be a good way to deal with the weak sensitivity of the parameters. In order to decrease the computation time, a parallel strategy is defined. It relies on a virtual enrichment of the meta-model, in order to compute q new objective functions in a parallel environment. Different methods of choosing the qnew objective functions are presented and compared. Speed-up tests show that Kriging Believer (KB) and minimum Constant Liar (CLmin) enrichments are suitable methods for this parallel EGO (EGO-p) algorithm. However, it must be noted that the most interesting speed-ups are observed for a small number of objective functions computed in parallel. Finally, the algorithm is successfully tested on a real parameters identification problem.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68945079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/AME.2020.131707
Sultana Mst. Nazma, Dhar Nikhil Ranjan
{"title":"Hybrid GRA-PCA and modified weighted TOPSIS coupled with Taguchi for multi-response process parameter optimization in turning AISI 1040 steel","authors":"Sultana Mst. Nazma, Dhar Nikhil Ranjan","doi":"10.24425/AME.2020.131707","DOIUrl":"https://doi.org/10.24425/AME.2020.131707","url":null,"abstract":"","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68945261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2021.137049
The article describes how different friction coefficients under certain cutting conditions and parameters affect the formation of the stress-strain and thermal states of the product when titanium alloy machining. A new research methodology is used for the study. Firstly, in the initial data for simulation, each time a different declared co-efficient of friction is proposed, and every such task of the cutting process modelling is solved for various cutting parameters. The second stage analyzes how these coeffi-cients influence the stress-strain and thermodynamic state of the workpiece and tool during cutting, as well as the tool wear dynamics. In the third stage of the study, ways for ensuring these analytically-grounded tribological cutting conditions are proposed. The analysis of different wear criteria in the simulation models of titanium alloys cutting is carried out. Experimental studies confirm simulation results.
{"title":"Comprehensive analysis of tribological factor influence on stress-strain and thermal state of workpiece during titanium alloys machining","authors":"","doi":"10.24425/ame.2021.137049","DOIUrl":"https://doi.org/10.24425/ame.2021.137049","url":null,"abstract":"The article describes how different friction coefficients under certain cutting conditions and parameters affect the formation of the stress-strain and thermal states of the product when titanium alloy machining. A new research methodology is used for the study. Firstly, in the initial data for simulation, each time a different declared co-efficient of friction is proposed, and every such task of the cutting process modelling is solved for various cutting parameters. The second stage analyzes how these coeffi-cients influence the stress-strain and thermodynamic state of the workpiece and tool during cutting, as well as the tool wear dynamics. In the third stage of the study, ways for ensuring these analytically-grounded tribological cutting conditions are proposed. The analysis of different wear criteria in the simulation models of titanium alloys cutting is carried out. Experimental studies confirm simulation results.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2021.138393
In theprevious study, wedesigned onepersonal rescue winchfor high-rise building rescue. Its key requirement is to be small and light enough to suit users. In addition to using lightweight and reasonable materials as in the proposed winch design, in this study, we proceed to optimize the weight of one two-level gear train, which accounts for a large proportion of weight. The first stage is building a weight optimization problem model with seven independent variables, establishing one optimal algorithm, and investigating the variables by Matlab software. The other is replacing the web material of the gears and pinions with Aluminum 6061-T6 and optimizing their hole diameters and hole numbers through using Ansys software. The obtained result shows a significant weight reduction. Compared to the original design, the weight reduces by 10.21% and 52.40% after the first optimal and last stages, respectively.
{"title":"Optimizing the weight of the two-level gear train in the personal rescue winch","authors":"","doi":"10.24425/ame.2021.138393","DOIUrl":"https://doi.org/10.24425/ame.2021.138393","url":null,"abstract":"In theprevious study, wedesigned onepersonal rescue winchfor high-rise building rescue. Its key requirement is to be small and light enough to suit users. In addition to using lightweight and reasonable materials as in the proposed winch design, in this study, we proceed to optimize the weight of one two-level gear train, which accounts for a large proportion of weight. The first stage is building a weight optimization problem model with seven independent variables, establishing one optimal algorithm, and investigating the variables by Matlab software. The other is replacing the web material of the gears and pinions with Aluminum 6061-T6 and optimizing their hole diameters and hole numbers through using Ansys software. The obtained result shows a significant weight reduction. Compared to the original design, the weight reduces by 10.21% and 52.40% after the first optimal and last stages, respectively.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135636136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2021.139314
This paper concerns the analytical investigation of the axisymmetric and steady flow of incompressible couple stress fluid through a rigid sphere embedded in a porous medium. In the porous region, the flow field is governed by Brinkman’s equation. Here we consider uniform flow at a distance from the sphere. The boundary conditions applied on the surface of the sphere are the slip condition and zero couple stress. Analytical solution of the problem in the terms of stream function is presented by modified Bessel functions. The drag experienced by an incompressible couple stress fluid on the sphere within the porous medium is calculated. The effects of the slip parameter, the couple stress parameter, and permeability on the drag are represented graphically. Special cases of viscous flow through a sphere are obtained and the results are compared with earlier published results.
{"title":"Couple stress fluid past a sphere embedded in a porous medium","authors":"","doi":"10.24425/ame.2021.139314","DOIUrl":"https://doi.org/10.24425/ame.2021.139314","url":null,"abstract":"This paper concerns the analytical investigation of the axisymmetric and steady flow of incompressible couple stress fluid through a rigid sphere embedded in a porous medium. In the porous region, the flow field is governed by Brinkman’s equation. Here we consider uniform flow at a distance from the sphere. The boundary conditions applied on the surface of the sphere are the slip condition and zero couple stress. Analytical solution of the problem in the terms of stream function is presented by modified Bessel functions. The drag experienced by an incompressible couple stress fluid on the sphere within the porous medium is calculated. The effects of the slip parameter, the couple stress parameter, and permeability on the drag are represented graphically. Special cases of viscous flow through a sphere are obtained and the results are compared with earlier published results.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2009.132098
Z. Hendzel, M. Szuster
In this work, a novel approach to designing an on-line tracking controller for a nonholonomic wheeled mobile robot (WMR) is presented. The controller consists of nonlinear neural feedback compensator, PD control law and supervisory element, which assure stability of the system. Neural network for feedback compensation is learned through approximate dynamic programming (ADP). To obtain stability in the learning phase and robustness in face of disturbances, an additional control signal derived from Lyapunov stability theorem based on the variable structure systems theory is provided. Verification of the proposed control algorithm was realized on a wheeled mobile robot Pioneer–2DX, and confirmed the assumed behavior of the control system.
{"title":"Approximate dynamic programming in robust tracking control of wheeled mobile robot","authors":"Z. Hendzel, M. Szuster","doi":"10.24425/ame.2009.132098","DOIUrl":"https://doi.org/10.24425/ame.2009.132098","url":null,"abstract":"In this work, a novel approach to designing an on-line tracking controller for a nonholonomic wheeled mobile robot (WMR) is presented. The controller consists of nonlinear neural feedback compensator, PD control law and supervisory element, which assure stability of the system. Neural network for feedback compensation is learned through approximate dynamic programming (ADP). To obtain stability in the learning phase and robustness in face of disturbances, an additional control signal derived from Lyapunov stability theorem based on the variable structure systems theory is provided. Verification of the proposed control algorithm was realized on a wheeled mobile robot Pioneer–2DX, and confirmed the assumed behavior of the control system.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135724064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2019.128445
Hamed Bagheri, Yaser Kiani, Mohammad Reza Eslami
{"title":"Buckling of moderately thick annular plates subjected to torque","authors":"Hamed Bagheri, Yaser Kiani, Mohammad Reza Eslami","doi":"10.24425/ame.2019.128445","DOIUrl":"https://doi.org/10.24425/ame.2019.128445","url":null,"abstract":"","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2021.137050
Roman Król
In this paper a versatile analysis of the cycloidal gearbox vibrations and the resonance phenomenon was performed. The objective of this work was to show resonance phenomenon and vibrations study in the multibody dynamics model and in the finite element model of the cycloidal gearbox. The output torque was analyzed as a function of the external sleeves stiffness. The results from the multibody dynamics model were verified in the finite element model using natural frequency with load stiffening, direct frequency response and direct transient response analyses. It was shown that natural frequencies of the cycloidal gearbox undergo changes during motion of the mechanism. The gearbox passes through the thresholds of the increased vibration amplitudes, which lead to excessive wear of the external sleeves. The analysis in the multibody dynamics model showed, that the increase in the external sleeves stiffness increases frequency of the second-order fluctuation at the output shaft. Small stiffness of the external sleeves guarantees lower frequency of the second order vibrations and higher peak-to-peak values of the output torque. The performed research plays important role in the cycloidal gearbox design. This work shows gearbox dynamics problems which are associated with wear of the external sleeves.
{"title":"Resonance phenomenon in the single stage cycloidal gearbox. Analysis of vibrations at the output shaft as a function of the external sleeves stiffness","authors":"Roman Król","doi":"10.24425/ame.2021.137050","DOIUrl":"https://doi.org/10.24425/ame.2021.137050","url":null,"abstract":"In this paper a versatile analysis of the cycloidal gearbox vibrations and the resonance phenomenon was performed. The objective of this work was to show resonance phenomenon and vibrations study in the multibody dynamics model and in the finite element model of the cycloidal gearbox. The output torque was analyzed as a function of the external sleeves stiffness. The results from the multibody dynamics model were verified in the finite element model using natural frequency with load stiffening, direct frequency response and direct transient response analyses. It was shown that natural frequencies of the cycloidal gearbox undergo changes during motion of the mechanism. The gearbox passes through the thresholds of the increased vibration amplitudes, which lead to excessive wear of the external sleeves. The analysis in the multibody dynamics model showed, that the increase in the external sleeves stiffness increases frequency of the second-order fluctuation at the output shaft. Small stiffness of the external sleeves guarantees lower frequency of the second order vibrations and higher peak-to-peak values of the output torque. The performed research plays important role in the cycloidal gearbox design. This work shows gearbox dynamics problems which are associated with wear of the external sleeves.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.24425/ame.2008.131626
Z. Stotsko, B. Diveyev, O. Ljubas
In most cases, road machines emit both acoustic and vibration energy into the fluids or structures surrounding the machinery. This is dangerous for the construction strength of the machinery, and is harmful for human health. There are two general classes of tools used to assess and optimize acoustic performance of a vehicle: test based methods, and Computer-Aided Engineering based methods. The second one is discussed in this paper.
{"title":"Vibro- and sound protection in road machines by means of vibration absorbing","authors":"Z. Stotsko, B. Diveyev, O. Ljubas","doi":"10.24425/ame.2008.131626","DOIUrl":"https://doi.org/10.24425/ame.2008.131626","url":null,"abstract":"In most cases, road machines emit both acoustic and vibration energy into the fluids or structures surrounding the machinery. This is dangerous for the construction strength of the machinery, and is harmful for human health. There are two general classes of tools used to assess and optimize acoustic performance of a vehicle: test based methods, and Computer-Aided Engineering based methods. The second one is discussed in this paper.","PeriodicalId":45083,"journal":{"name":"Archive of Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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