Pub Date : 2023-01-12DOI: 10.1177/03093247221145792
Eman A. N. Al-Lehaibi
For the first time, numerical solutions were computed using fractional-order strain considerations in the current study. For an isotropic and homogeneous nanobeam, the thermoelasticity with one relaxation time and fractional-order strain theory based on Caputo–Fabrizio’s definition of fractional derivative was examined. With thermal loading and in simply supported boundary conditions, the Laplace transformations have been used upon the governing equations and its inversion was computed using the Tzou technique approximation. The numerical calculations for a thermoelastic rectangular gold (Au) nanobeam have been validated as a model where ramp-type heat is considered. The computational solutions have been depicted in two-dimensions graphs for several situations to investigate the impact of the fractional-order and ramping heat parameters on all of the functions studied. The temperature increment distribution, lateral vibration, deformation, tension, and energy density are all influenced by fractional-order and ramp-time heat parameters. The ramp-time heat parameter might be utilized to regulate nanobeam vibration and energy damping in thermoelastic nanobeams.
{"title":"The vibration of a gold nanobeam under the thermoelasticity fractional-order strain theory based on Caputo–Fabrizio’s definition","authors":"Eman A. N. Al-Lehaibi","doi":"10.1177/03093247221145792","DOIUrl":"https://doi.org/10.1177/03093247221145792","url":null,"abstract":"For the first time, numerical solutions were computed using fractional-order strain considerations in the current study. For an isotropic and homogeneous nanobeam, the thermoelasticity with one relaxation time and fractional-order strain theory based on Caputo–Fabrizio’s definition of fractional derivative was examined. With thermal loading and in simply supported boundary conditions, the Laplace transformations have been used upon the governing equations and its inversion was computed using the Tzou technique approximation. The numerical calculations for a thermoelastic rectangular gold (Au) nanobeam have been validated as a model where ramp-type heat is considered. The computational solutions have been depicted in two-dimensions graphs for several situations to investigate the impact of the fractional-order and ramping heat parameters on all of the functions studied. The temperature increment distribution, lateral vibration, deformation, tension, and energy density are all influenced by fractional-order and ramp-time heat parameters. The ramp-time heat parameter might be utilized to regulate nanobeam vibration and energy damping in thermoelastic nanobeams.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89789259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-12DOI: 10.1177/03093247221141490
V. F. Sciuti, R. Vargas, R. B. Canto, F. Hild
Damage due to MgO hydration in castables has been studied by bar resonance and recently by Digital Image Correlation (DIC). The hydration reaction kinetics was studied via principal component analyses (PCA) applied to DIC results of images acquired during 60 h of curing and drying of an MgO containing refractory castable. The experiment was carried out in a in-house climatic chamber at 50°C and 50% of relative air humidity. The displacement and maximum eigen strain fields were obtained via DIC. Their PCA revealed the crack network as the most relevant component, with a temporal development of a sigmoidal curve where a two-parameter Weibull law was satisfactorily fitted. The reaction duration was virtually identical for both fields, and only a time shift in reaction initiation and saturation was attributed to the choice of field. The approach allows the need for user-defined thresholds to be avoided for crack quantification.
{"title":"Modal characterization of crack network development in an MgO containing refractory castable","authors":"V. F. Sciuti, R. Vargas, R. B. Canto, F. Hild","doi":"10.1177/03093247221141490","DOIUrl":"https://doi.org/10.1177/03093247221141490","url":null,"abstract":"Damage due to MgO hydration in castables has been studied by bar resonance and recently by Digital Image Correlation (DIC). The hydration reaction kinetics was studied via principal component analyses (PCA) applied to DIC results of images acquired during 60 h of curing and drying of an MgO containing refractory castable. The experiment was carried out in a in-house climatic chamber at 50°C and 50% of relative air humidity. The displacement and maximum eigen strain fields were obtained via DIC. Their PCA revealed the crack network as the most relevant component, with a temporal development of a sigmoidal curve where a two-parameter Weibull law was satisfactorily fitted. The reaction duration was virtually identical for both fields, and only a time shift in reaction initiation and saturation was attributed to the choice of field. The approach allows the need for user-defined thresholds to be avoided for crack quantification.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74227945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-23DOI: 10.1177/03093247221140981
Samaneh Pourolajal, G. Majzoobi
Stress-strain curves of materials normally change with strain rate and temperature and are normally defined by material models. In this study, a new technique was developed for determining the constants of material models. This technique was based on dynamic indentation test, numerical simulation using Ls-dyna code and artificial neural network. An indenter of tapered shape was shot against the materials as the target by a gas gun. The experiments were carried out for four strain rates and four temperatures. The target was made of pure copper. The penetration depth-time and load-time histories were captured by a LVDT and a piezoelectric load-cell, respectively and the load-penetration depth curve (P-h) was obtained. This curve is characterized by five parameters which are determined for each indentation test. On the other hand, the indentation test was simulated using Ls-dyna hydrocode. From the simulations, the P-h curves were obtained using Johnson-Cook (J-C) and Zerilli-Armstrong (Z-A) material models and the characterizing parameters of the numerical P-h curves were also identified. Finally, an artificial neural network (ANN) was trained by the numerical P-h curves parameters as the input and the constants of J-C and Z-A models as the output. The trained neural network was then tested by the experimental p-h curves parameters as the input and the constants of J-C and Z-A models as the output. Moreover, a number of dynamic compression tests were performed using the well-known Split Hopkinson Bar at the same strain rates and temperatures used for indentation tests and the stress-strain curves of material were obtained. A reasonable agreement was observed between the stress-strain curves predicted by neural network and the Split Hopkinson Bar. The proposed method does not need sophisticated instrumentation and in fact, the load-time and indentation depth-time histories are directly converted to stress-strain of material using an artificial neural network.
{"title":"Determination of the parameters of material models using dynamic indentation test and artificial neural network","authors":"Samaneh Pourolajal, G. Majzoobi","doi":"10.1177/03093247221140981","DOIUrl":"https://doi.org/10.1177/03093247221140981","url":null,"abstract":"Stress-strain curves of materials normally change with strain rate and temperature and are normally defined by material models. In this study, a new technique was developed for determining the constants of material models. This technique was based on dynamic indentation test, numerical simulation using Ls-dyna code and artificial neural network. An indenter of tapered shape was shot against the materials as the target by a gas gun. The experiments were carried out for four strain rates and four temperatures. The target was made of pure copper. The penetration depth-time and load-time histories were captured by a LVDT and a piezoelectric load-cell, respectively and the load-penetration depth curve (P-h) was obtained. This curve is characterized by five parameters which are determined for each indentation test. On the other hand, the indentation test was simulated using Ls-dyna hydrocode. From the simulations, the P-h curves were obtained using Johnson-Cook (J-C) and Zerilli-Armstrong (Z-A) material models and the characterizing parameters of the numerical P-h curves were also identified. Finally, an artificial neural network (ANN) was trained by the numerical P-h curves parameters as the input and the constants of J-C and Z-A models as the output. The trained neural network was then tested by the experimental p-h curves parameters as the input and the constants of J-C and Z-A models as the output. Moreover, a number of dynamic compression tests were performed using the well-known Split Hopkinson Bar at the same strain rates and temperatures used for indentation tests and the stress-strain curves of material were obtained. A reasonable agreement was observed between the stress-strain curves predicted by neural network and the Split Hopkinson Bar. The proposed method does not need sophisticated instrumentation and in fact, the load-time and indentation depth-time histories are directly converted to stress-strain of material using an artificial neural network.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75553814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-24DOI: 10.1177/03093247221138344
E. Patterson, E. Hack
The extent of the domain over which a model validation demonstrates the reliability of a model is discussed and a simple schematic diagram is used to illustrate the domain. The schematic diagram can also be used to optimise the physical test campaign required to demonstrate the reliability of a model for its context of use. The connections to existing validation approaches and procedures are discussed.
{"title":"Validating out of the box: Identifying a campaign of physical tests","authors":"E. Patterson, E. Hack","doi":"10.1177/03093247221138344","DOIUrl":"https://doi.org/10.1177/03093247221138344","url":null,"abstract":"The extent of the domain over which a model validation demonstrates the reliability of a model is discussed and a simple schematic diagram is used to illustrate the domain. The schematic diagram can also be used to optimise the physical test campaign required to demonstrate the reliability of a model for its context of use. The connections to existing validation approaches and procedures are discussed.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72849897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-21DOI: 10.1177/03093247221135210
M. Eghbali, S. A. Hosseini, M. Pourseifi
This paper examines the free lateral vibration of a cracked nano-beam based on Euler-Bernoulli beam theory and nonlocal strain gradient theory (NSGT). Due to the importance and application of nanostructures, their mechanical and mechanical properties are essential. The governing equations and boundary conditions related to using the Hamilton principle have been extracted. The beam separation with the nano-beams division into two parts attached to the Torsion spring is modeled. The model calls the excess strain energy due to crack and increases the discontinuity in the deflection slope. This study investigated the effects of crack propagation, crack intensity, material length scale parameter, and various nonlocal parameters. A comparison of previous studies has been published, where a good agreement is observed. The results show that the parameters mentioned above play an important role in dynamical behavior.
{"title":"An dynamical evaluation of size-dependent weakened nano-beam based on the nonlocal strain gradient theory","authors":"M. Eghbali, S. A. Hosseini, M. Pourseifi","doi":"10.1177/03093247221135210","DOIUrl":"https://doi.org/10.1177/03093247221135210","url":null,"abstract":"This paper examines the free lateral vibration of a cracked nano-beam based on Euler-Bernoulli beam theory and nonlocal strain gradient theory (NSGT). Due to the importance and application of nanostructures, their mechanical and mechanical properties are essential. The governing equations and boundary conditions related to using the Hamilton principle have been extracted. The beam separation with the nano-beams division into two parts attached to the Torsion spring is modeled. The model calls the excess strain energy due to crack and increases the discontinuity in the deflection slope. This study investigated the effects of crack propagation, crack intensity, material length scale parameter, and various nonlocal parameters. A comparison of previous studies has been published, where a good agreement is observed. The results show that the parameters mentioned above play an important role in dynamical behavior.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73510065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-10DOI: 10.1177/03093247221135413
Yunfei Deng, Ruiwen Wang, Yinbo Zhang, Huapeng Wu, Gang Wei
1060-H112 aluminum alloy with high ductility is widely used in industrial engineering. The study of its dynamic mechanical behavior has theoretical and engineering application value. In this paper, quasi-static tensile tests from room temperature to 250°C and high strain rate compression tests were conducted using a universal material testing machine and a Hopkinson compression bar. By using a hybrid test-numerical simulation method, a modified Johnson-Cook (MJC) strength model and Cockcroft-Latham (C-L) fracture criterion parameters were calibrated. Subsequently, Taylor impact tests were performed on 1060-H112 aluminum alloy specimens with a diameter of 12.66 mm and a length of 50.64 mm in the range of 176.3–483.03 m/s. Upsetting and tensile tearing were observed in the tests. A 12.68 mm diameter blunt nosed projectile impact test on 2 mm 1060-H112 aluminum alloy plate was also conducted with a light gas gun system, and the speed related parameters and failure modes were obtained. Finally, a three-dimensional model corresponding to the test was established in ABAQUS/Explicit finite element simulation software, and the failure modes of the Taylor rod and the velocity parameters and failure modes of the target impact test were predicted. The results show that the MJC strength model and the C-L fracture criterion can predict the experimental results of the two tests accurately. It shows that the MJC strength model and C-L fracture criterion have high accuracy, and they will play an important role in the application of 1060-H112 aluminum alloy in industrial engineering.
{"title":"Study of dynamic mechanical behavior of 1060-H112 aluminum alloy: Experimental and numerical simulation","authors":"Yunfei Deng, Ruiwen Wang, Yinbo Zhang, Huapeng Wu, Gang Wei","doi":"10.1177/03093247221135413","DOIUrl":"https://doi.org/10.1177/03093247221135413","url":null,"abstract":"1060-H112 aluminum alloy with high ductility is widely used in industrial engineering. The study of its dynamic mechanical behavior has theoretical and engineering application value. In this paper, quasi-static tensile tests from room temperature to 250°C and high strain rate compression tests were conducted using a universal material testing machine and a Hopkinson compression bar. By using a hybrid test-numerical simulation method, a modified Johnson-Cook (MJC) strength model and Cockcroft-Latham (C-L) fracture criterion parameters were calibrated. Subsequently, Taylor impact tests were performed on 1060-H112 aluminum alloy specimens with a diameter of 12.66 mm and a length of 50.64 mm in the range of 176.3–483.03 m/s. Upsetting and tensile tearing were observed in the tests. A 12.68 mm diameter blunt nosed projectile impact test on 2 mm 1060-H112 aluminum alloy plate was also conducted with a light gas gun system, and the speed related parameters and failure modes were obtained. Finally, a three-dimensional model corresponding to the test was established in ABAQUS/Explicit finite element simulation software, and the failure modes of the Taylor rod and the velocity parameters and failure modes of the target impact test were predicted. The results show that the MJC strength model and the C-L fracture criterion can predict the experimental results of the two tests accurately. It shows that the MJC strength model and C-L fracture criterion have high accuracy, and they will play an important role in the application of 1060-H112 aluminum alloy in industrial engineering.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82484174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-08DOI: 10.1177/03093247221133602
Qiyong Yang, Chaosheng Song, Siyuan Liu
Aviation thin-walled spiral bevel gears are prone to traveling wave vibration. This study proposes an efficient traveling wave vibration analysis method based on the contact finite element model of the spiral bevel gears. The excitation vibration modes under the typical working condition is obtained through comparison to the modal analysis and harmonic response analysis. The resonance modes and frequencies are determined by Campbell diagram. The effect of thin-walled structure parameters on the traveling wave vibration of aviation spiral bevel gears is investigated. The results show that the traveling wave vibration of the gear is easily excited by the forward traveling wave and backward traveling wave resonance of 2nd nodal diameter/1st nodal circle, forward traveling wave resonance of the 6th nodal diameter, backward traveling wave resonance of 7th nodal diameter. The increase of gear blank web thickness will decrease peak stresses. The increase of conical web thickness and angle will decrease the peak stresses of compound vibration. The adjacent modals will aggravate the vibration. The decrease of the modal frequency spacing will increase the peak stresses.
{"title":"Computerized analysis of traveling wave vibration characteristics of aviation thin-walled spiral bevel gears","authors":"Qiyong Yang, Chaosheng Song, Siyuan Liu","doi":"10.1177/03093247221133602","DOIUrl":"https://doi.org/10.1177/03093247221133602","url":null,"abstract":"Aviation thin-walled spiral bevel gears are prone to traveling wave vibration. This study proposes an efficient traveling wave vibration analysis method based on the contact finite element model of the spiral bevel gears. The excitation vibration modes under the typical working condition is obtained through comparison to the modal analysis and harmonic response analysis. The resonance modes and frequencies are determined by Campbell diagram. The effect of thin-walled structure parameters on the traveling wave vibration of aviation spiral bevel gears is investigated. The results show that the traveling wave vibration of the gear is easily excited by the forward traveling wave and backward traveling wave resonance of 2nd nodal diameter/1st nodal circle, forward traveling wave resonance of the 6th nodal diameter, backward traveling wave resonance of 7th nodal diameter. The increase of gear blank web thickness will decrease peak stresses. The increase of conical web thickness and angle will decrease the peak stresses of compound vibration. The adjacent modals will aggravate the vibration. The decrease of the modal frequency spacing will increase the peak stresses.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82984292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-19DOI: 10.1177/03093247221122052
Aanchal Yadav, G. Bhardwaj, R. K. Godara
This paper is aimed to investigate the fracture behaviour of carbon nanotube (CNT) reinforced composite exposed to the thermo-mechanical environment in the presence of discontinuities using the extended isogeometric analysis (XIGA) method. The study focuses on finding the effects of discontinuities present in a finite plate with a pre-existing crack, on the stress intensity factors (SIFs). The mandatory equivalent mechanical and thermal properties are assessed with the help of various micromechanics models. Two types of CNTs are assumed to be reinforced in the epoxy-matrix: single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT). The CNT reinforced composite is examined for varying volume percentages of CNTs reinforcement. A comparative study is provided to see the influence of mechanical and coupled thermo-mechanical load on SIFs. Adiabatic crack is taken into account for the computational simulation for thermal loading condition. The interaction integral method is used for the extraction of SIFs. The findings of the test reveal that with the rise in the volume percentage of CNTs, the properties such as fracture energy and fracture toughness also rise. Moreover, the fracture of CNT reinforced composites is delayed with the increased content of CNT. The results establish the profound influence of holes on SIFs than the inclusions.
{"title":"Influence of discontinuities on the fracture behaviour of CNT reinforced composites subjected to thermo-mechanical load using XIGA","authors":"Aanchal Yadav, G. Bhardwaj, R. K. Godara","doi":"10.1177/03093247221122052","DOIUrl":"https://doi.org/10.1177/03093247221122052","url":null,"abstract":"This paper is aimed to investigate the fracture behaviour of carbon nanotube (CNT) reinforced composite exposed to the thermo-mechanical environment in the presence of discontinuities using the extended isogeometric analysis (XIGA) method. The study focuses on finding the effects of discontinuities present in a finite plate with a pre-existing crack, on the stress intensity factors (SIFs). The mandatory equivalent mechanical and thermal properties are assessed with the help of various micromechanics models. Two types of CNTs are assumed to be reinforced in the epoxy-matrix: single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT). The CNT reinforced composite is examined for varying volume percentages of CNTs reinforcement. A comparative study is provided to see the influence of mechanical and coupled thermo-mechanical load on SIFs. Adiabatic crack is taken into account for the computational simulation for thermal loading condition. The interaction integral method is used for the extraction of SIFs. The findings of the test reveal that with the rise in the volume percentage of CNTs, the properties such as fracture energy and fracture toughness also rise. Moreover, the fracture of CNT reinforced composites is delayed with the increased content of CNT. The results establish the profound influence of holes on SIFs than the inclusions.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89817127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-15DOI: 10.1177/03093247221119303
H. Youssef, Eman A. N. Al-Lehaibi
In this work, the two-temperature dual-phase-lag theorem has been used to present an analytical mathematical model for calculating the vibration in a viscothermoelastic nano-resonator. The governing equations have been derived when a simply supported nano-resonator is exposed to a ramp-type thermal load and static pre-stress. The governing equations have been solved by using a direct method and obtained the solution in the Laplace transform domain where the inversions of the Laplace transform have been calculated by using the Tzou approximation method. The increments of the dynamic and conductive temperatures, volumetric deformation, and stress regarding the resonator length for various cases of temperature type, static-pre-stress, and viscothermoelastic properties with different values of ramping heat parameter have been presented in figures and studied. The parameter of the two-temperature model, static pre-stress, ramp-type heat parameter, and viscothermoelastic parameter has a significant impact on all functions studied. The ramping time parameter may be utilized to change the thermal and mechanical properties of the nano-resonator.
{"title":"The vibration of viscothermoelastic static pre-stress nanobeam based on two-temperature dual-phase-lag heat conduction and subjected to ramp-type heat","authors":"H. Youssef, Eman A. N. Al-Lehaibi","doi":"10.1177/03093247221119303","DOIUrl":"https://doi.org/10.1177/03093247221119303","url":null,"abstract":"In this work, the two-temperature dual-phase-lag theorem has been used to present an analytical mathematical model for calculating the vibration in a viscothermoelastic nano-resonator. The governing equations have been derived when a simply supported nano-resonator is exposed to a ramp-type thermal load and static pre-stress. The governing equations have been solved by using a direct method and obtained the solution in the Laplace transform domain where the inversions of the Laplace transform have been calculated by using the Tzou approximation method. The increments of the dynamic and conductive temperatures, volumetric deformation, and stress regarding the resonator length for various cases of temperature type, static-pre-stress, and viscothermoelastic properties with different values of ramping heat parameter have been presented in figures and studied. The parameter of the two-temperature model, static pre-stress, ramp-type heat parameter, and viscothermoelastic parameter has a significant impact on all functions studied. The ramping time parameter may be utilized to change the thermal and mechanical properties of the nano-resonator.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78586448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-12DOI: 10.1177/03093247221122691
Wei Peng, Zezhang Qi, Tianhu He
Ultra-slow relaxation process of polymers has the memory-dependent feature, integer-order thermoviscoelastic models may fail to describe the dynamic behaviors of viscoelastic structures accurately. Additionally, it is noticed that the small-scale effect of elastic deformation and heat conduction in a non-isothermal temperature environment is becoming significant due to the development of micro-devices. To better capture the memory-dependent effect and the small-scale effect of viscoelastic micro-structures in heat transfer environment, as a first attempt, present work focuses on developing a refined fractional Kelvin-Voigt thermoviscoelastic model by incorporating the nonlocal dual-phase-lag (NDPL) heat conduction model and the modified coupled stress theory (MCST). Then, the model is applied to investigating the transient response of a polymer microbeam subjected to a harmonic thermal loading. The governing equations involving the modified parameters are formulated and then solved by Laplace transform method. Some parametric results are demonstrated to display the impacts of the nonlocal thermal parameter, the material length-scale parameter and the fractional-order parameter on the considered physical quantities. The results show that the small-scale effect and the memory-dependent effects strongly depend on the polymer micro-structure characteristics in thermal environment.
{"title":"Nonlocal dual-phase-lag thermoviscoelastic response of a polymer microbeam incorporating modified couple stress and fractional viscoelastic theories","authors":"Wei Peng, Zezhang Qi, Tianhu He","doi":"10.1177/03093247221122691","DOIUrl":"https://doi.org/10.1177/03093247221122691","url":null,"abstract":"Ultra-slow relaxation process of polymers has the memory-dependent feature, integer-order thermoviscoelastic models may fail to describe the dynamic behaviors of viscoelastic structures accurately. Additionally, it is noticed that the small-scale effect of elastic deformation and heat conduction in a non-isothermal temperature environment is becoming significant due to the development of micro-devices. To better capture the memory-dependent effect and the small-scale effect of viscoelastic micro-structures in heat transfer environment, as a first attempt, present work focuses on developing a refined fractional Kelvin-Voigt thermoviscoelastic model by incorporating the nonlocal dual-phase-lag (NDPL) heat conduction model and the modified coupled stress theory (MCST). Then, the model is applied to investigating the transient response of a polymer microbeam subjected to a harmonic thermal loading. The governing equations involving the modified parameters are formulated and then solved by Laplace transform method. Some parametric results are demonstrated to display the impacts of the nonlocal thermal parameter, the material length-scale parameter and the fractional-order parameter on the considered physical quantities. The results show that the small-scale effect and the memory-dependent effects strongly depend on the polymer micro-structure characteristics in thermal environment.","PeriodicalId":50038,"journal":{"name":"Journal of Strain Analysis for Engineering Design","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90162026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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