Pub Date : 2023-11-06DOI: 10.24425/AME.2019.128446
D. Roy, R. Tiwari
In the present work, a procedure for the estimation of internal damping in a cracked rotor system is described. The internal (or rotating) damping is one of the important rotor system parameters and it contributes to the instability of the system above its critical speed. A rotor with a crack during fatigue loading has rubbing action between the two crack faces,which contributes to the internal damping.Hence, internal damping estimation also can be an indicator of the presence of a crack. A cracked rotor system with an offset disc, which incorporates the rotary and translatory of inertia and gyroscopic effect of the disc is considered. The transverse crack is modeled based on the switching crack assumption, which gives multiple harmonics excitation to the rotor system.Moreover, due to the crack asymmetry, the multiple harmonic excitations leads to the forward and backward whirls in the rotor orbit. Based on equations of motions derived in the frequency domain (full spectrum), an estimation procedure is evolved to identify the internal and external damping, the additive crack stiffness and unbalance in the rotor system. Numerically, the identification procedure is tested using noisy responses and bias errors in system parameters.
{"title":"Development of identification procedure for the internal and external damping in a cracked rotor system undergoing forward and backward whirls","authors":"D. Roy, R. Tiwari","doi":"10.24425/AME.2019.128446","DOIUrl":"https://doi.org/10.24425/AME.2019.128446","url":null,"abstract":"In the present work, a procedure for the estimation of internal damping in a cracked rotor system is described. The internal (or rotating) damping is one of the important rotor system parameters and it contributes to the instability of the system above its critical speed. A rotor with a crack during fatigue loading has rubbing action between the two crack faces,which contributes to the internal damping.Hence, internal damping estimation also can be an indicator of the presence of a crack. A cracked rotor system with an offset disc, which incorporates the rotary and translatory of inertia and gyroscopic effect of the disc is considered. The transverse crack is modeled based on the switching crack assumption, which gives multiple harmonics excitation to the rotor system.Moreover, due to the crack asymmetry, the multiple harmonic excitations leads to the forward and backward whirls in the rotor orbit. Based on equations of motions derived in the frequency domain (full spectrum), an estimation procedure is evolved to identify the internal and external damping, the additive crack stiffness and unbalance in the rotor system. Numerically, the identification procedure is tested using noisy responses and bias errors in system parameters.","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":"68944953","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.2008.131633
M. Skorupa, A. Korbel
For riveted joints with eccentricities of the load path, bending moments referred to as secondary bending are induced under nominally tensile loading conditions. Two simple theoretical models proposed in the literature to estimate the associated bending stresses are evaluated in the paper. Both approaches have been implemented in computer programs and applied to estimate the effect of several variables on the calculated bending stresses in the lap joint. Possibilities of the experimental and numerical verification of the models are also considered. Finally, a correlation between the secondary bending computed by one of the simple models and the observed fatigue properties of riveted specimens, as reported in the literature, is investigated. It is shown that deviations of the experimental results from the theoretical expectations stem from additional to secondary bending factors, like the inhomogeneous load transmission through the joint and the residual stresses induced by riveting process. These phenomena are known to be relevant to the fatigue behaviour of riveted joints, but they are not accounted for by the simple models. A conclusion from the present study is that despite the limitations and approximations inherent in the simple models, they provide reliable estimates of nominal bending stresses at the critical rivet rows and can be utilized in currently used semi-empirical concepts for predictions on the fatigue life of riveted joints.
{"title":"Modelling the secondary bending in riveted joints with eccentricities","authors":"M. Skorupa, A. Korbel","doi":"10.24425/ame.2008.131633","DOIUrl":"https://doi.org/10.24425/ame.2008.131633","url":null,"abstract":"For riveted joints with eccentricities of the load path, bending moments referred to as secondary bending are induced under nominally tensile loading conditions. Two simple theoretical models proposed in the literature to estimate the associated bending stresses are evaluated in the paper. Both approaches have been implemented in computer programs and applied to estimate the effect of several variables on the calculated bending stresses in the lap joint. Possibilities of the experimental and numerical verification of the models are also considered. Finally, a correlation between the secondary bending computed by one of the simple models and the observed fatigue properties of riveted specimens, as reported in the literature, is investigated. It is shown that deviations of the experimental results from the theoretical expectations stem from additional to secondary bending factors, like the inhomogeneous load transmission through the joint and the residual stresses induced by riveting process. These phenomena are known to be relevant to the fatigue behaviour of riveted joints, but they are not accounted for by the simple models. A conclusion from the present study is that despite the limitations and approximations inherent in the simple models, they provide reliable estimates of nominal bending stresses at the critical rivet rows and can be utilized in currently used semi-empirical concepts for predictions on the fatigue life of riveted joints.","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":"135544849","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.2008.131623
S. Chwastek, S. Michałowski
Vibration intensity in mobile machines depends on the road roughness profile, ride velocity and dissipative properties of machine components. To reduce vibrations of a mobile machine with a boom equipment one of the available passive methods, utilizing a hydropnematic system for boom support to improve flexibility, the system incorporating throttling valves. Energy dissipation in a hydropneumatic system controls the decay of vibrations of the machine body and equipment. In the range of large velocities, passive methods prove inadequate. When ride velocity is to be increased, at the same time the required safety features and stabilization of the position of machine equipment are to be provided, further dynamic analyses are fully merited to identify processes taking place in the driving system. The final result should be the synthesis of the LQR control system to modulate the loading characteristics of the motor and to control the flow in a hydraulic boom-support system.
{"title":"Optimal stabilization of equipment in unsprung mobile machines","authors":"S. Chwastek, S. Michałowski","doi":"10.24425/ame.2008.131623","DOIUrl":"https://doi.org/10.24425/ame.2008.131623","url":null,"abstract":"Vibration intensity in mobile machines depends on the road roughness profile, ride velocity and dissipative properties of machine components. To reduce vibrations of a mobile machine with a boom equipment one of the available passive methods, utilizing a hydropnematic system for boom support to improve flexibility, the system incorporating throttling valves. Energy dissipation in a hydropneumatic system controls the decay of vibrations of the machine body and equipment. In the range of large velocities, passive methods prove inadequate. When ride velocity is to be increased, at the same time the required safety features and stabilization of the position of machine equipment are to be provided, further dynamic analyses are fully merited to identify processes taking place in the driving system. The final result should be the synthesis of the LQR control system to modulate the loading characteristics of the motor and to control the flow in a hydraulic boom-support 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":"135544858","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.2009.132103
J. Knapczyk, M. Maniowski
{"title":"Methods of geometric parameters estimation for a mechanism based on point coordinates measurements","authors":"J. Knapczyk, M. Maniowski","doi":"10.24425/ame.2009.132103","DOIUrl":"https://doi.org/10.24425/ame.2009.132103","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":"135544901","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.2008.131620
A. Banaszek
The paper presents the influence of different liquid cargo properties on discharge rate of hydraulic submerged cargo pumps on modern product and chemical tankers is presented in the paper. Main parts of submerged cargo pumps and hydraulic drive system are described. Some examples of technical solutions of the described systems installed on board of the newly building constructed ship m/t ‘Helix’ are presented. The formula of use application of flow and drive characteristics of cargo pumps is given. These characteristics were made derived for a basic cargo (fresh water) for the case of the service of a real cargo of different viscosity and density.
{"title":"The influence of liquid cargo properties on the discharge rate of submerged cargo pumps with hydraulic drive on modern product and chemical tankers","authors":"A. Banaszek","doi":"10.24425/ame.2008.131620","DOIUrl":"https://doi.org/10.24425/ame.2008.131620","url":null,"abstract":"The paper presents the influence of different liquid cargo properties on discharge rate of hydraulic submerged cargo pumps on modern product and chemical tankers is presented in the paper. Main parts of submerged cargo pumps and hydraulic drive system are described. Some examples of technical solutions of the described systems installed on board of the newly building constructed ship m/t ‘Helix’ are presented. The formula of use application of flow and drive characteristics of cargo pumps is given. These characteristics were made derived for a basic cargo (fresh water) for the case of the service of a real cargo of different viscosity and density.","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":"135544904","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.2008.131632
J. Kowal, J. Snamina, A. Podsiadło, J. Konieczny
The paper is concerned with an analysis of behaviour of the cableway. On the basis of design data and results of adequate experiments, a physical model of cableway was formulated. The static of cableway was developed assuming a full nonlinear model based on elastic catenary curve. The tension of the rope and the reactive forces between the rope and the supports were calculated. Assuming various loadings of the rope, the relation between the tension in bottom and upper stations and the length of the rope was determined. The model describing the motion of the system is linear. Finite elements were used to formulate the model. Two methods of accelerating the system were investigated.
{"title":"Static and dynamic analysis of the cableway","authors":"J. Kowal, J. Snamina, A. Podsiadło, J. Konieczny","doi":"10.24425/ame.2008.131632","DOIUrl":"https://doi.org/10.24425/ame.2008.131632","url":null,"abstract":"The paper is concerned with an analysis of behaviour of the cableway. On the basis of design data and results of adequate experiments, a physical model of cableway was formulated. The static of cableway was developed assuming a full nonlinear model based on elastic catenary curve. The tension of the rope and the reactive forces between the rope and the supports were calculated. Assuming various loadings of the rope, the relation between the tension in bottom and upper stations and the length of the rope was determined. The model describing the motion of the system is linear. Finite elements were used to formulate the model. Two methods of accelerating the system were investigated.","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":"135544908","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.2021.138397
Reza Taghipour, Mina Roodgar Nashta, Mohsen Bozorgnasab, Hessam Mirgolbabaei
The structural damages can lead to structural failure if they are not identified at early stages. Different methods for detecting and locating the damages in structures have been always appealing to designers in the field. Due to direct relation between the stiffness, natural frequency, and mode shapes in the structure, the modal parameters could be used for the purpose of detecting and locating the damages in structures. In the current study, a new damage indicator named “DLI” is proposed, using the mode shapes and their derivatives. A finite element model of a beam is used, and the numerical model is validated against experimental data. The proposed index is investigated for two beams with different support conditions and the results are compared with those of two well-known indices – MSEBI and CDF. To show the capability and accuracy of the proposed index, the damages with low severity at various locations of the structures containing the elements near the supports were investigated. The results under noisy conditions are investigated by considering 3% and 5% noise on modal data. The results show a high level of accuracy of the proposed index for identifying the location of the damaged elements in beams.
{"title":"A new index for damage identification in beam structures based on modal parameters","authors":"Reza Taghipour, Mina Roodgar Nashta, Mohsen Bozorgnasab, Hessam Mirgolbabaei","doi":"10.24425/ame.2021.138397","DOIUrl":"https://doi.org/10.24425/ame.2021.138397","url":null,"abstract":"The structural damages can lead to structural failure if they are not identified at early stages. Different methods for detecting and locating the damages in structures have been always appealing to designers in the field. Due to direct relation between the stiffness, natural frequency, and mode shapes in the structure, the modal parameters could be used for the purpose of detecting and locating the damages in structures. In the current study, a new damage indicator named “DLI” is proposed, using the mode shapes and their derivatives. A finite element model of a beam is used, and the numerical model is validated against experimental data. The proposed index is investigated for two beams with different support conditions and the results are compared with those of two well-known indices – MSEBI and CDF. To show the capability and accuracy of the proposed index, the damages with low severity at various locations of the structures containing the elements near the supports were investigated. The results under noisy conditions are investigated by considering 3% and 5% noise on modal data. The results show a high level of accuracy of the proposed index for identifying the location of the damaged elements in beams.","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":"135584647","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.2023.148125
{"title":"148125","authors":"","doi":"10.24425/ame.2023.148125","DOIUrl":"https://doi.org/10.24425/ame.2023.148125","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":"135584871","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.2021.137044
{"title":"Slow flow past a weakly permeable spheroidal particle in a hypothetical cell","authors":"","doi":"10.24425/ame.2021.137044","DOIUrl":"https://doi.org/10.24425/ame.2021.137044","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":"135637055","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.2007.131561
Łukasz Maciejewski, Wojciech Myszka, Grażyna Ziętek
In the paper, the authors present the approach to modelling of austenitic steel hardening basing on the Frederick-Armstrong’s rule and Chaboche elastic-plastic material model with mixed hardening. Non-linear uniaxial constitutive equations are derived from more general relations with the assumption of an appropriate evolution of back stress. The aim of the paper is to propose a robust and efficient identification method of a well known material model. A typical LCF strain-controlled test was conducted for selected amplitudes of total strain. Continuous measurements of instant stress and total strain values were performed. Life time of a specimen, signals amplitudes and load frequency were also recorded. Based on the measurement, identification of constitutive equation parameters was performed. The goal was to obtain a model that describes, including hardening phenomenon, a material behaviour during the experiment until the material failure. As a criterion of optimisation of the model least square projection accuracy of the material response was selected. Several optimisation methods were examined. Finally, the differential evolution method was selected as the most efficient one. The method was compared to standard optimisation methods available in the MATLAB environment. Significant decrease of computation time was achieved as all the optimisation procedures were run parallel on a computer cluster.
{"title":"Application of differential evolution algorithm for identification of experimental data","authors":"Łukasz Maciejewski, Wojciech Myszka, Grażyna Ziętek","doi":"10.24425/ame.2007.131561","DOIUrl":"https://doi.org/10.24425/ame.2007.131561","url":null,"abstract":"In the paper, the authors present the approach to modelling of austenitic steel hardening basing on the Frederick-Armstrong’s rule and Chaboche elastic-plastic material model with mixed hardening. Non-linear uniaxial constitutive equations are derived from more general relations with the assumption of an appropriate evolution of back stress. The aim of the paper is to propose a robust and efficient identification method of a well known material model. A typical LCF strain-controlled test was conducted for selected amplitudes of total strain. Continuous measurements of instant stress and total strain values were performed. Life time of a specimen, signals amplitudes and load frequency were also recorded. Based on the measurement, identification of constitutive equation parameters was performed. The goal was to obtain a model that describes, including hardening phenomenon, a material behaviour during the experiment until the material failure. As a criterion of optimisation of the model least square projection accuracy of the material response was selected. Several optimisation methods were examined. Finally, the differential evolution method was selected as the most efficient one. The method was compared to standard optimisation methods available in the MATLAB environment. Significant decrease of computation time was achieved as all the optimisation procedures were run parallel on a computer cluster.","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":"135637388","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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