首页 > 最新文献

Meccanica最新文献

英文 中文
Rarefaction pulses on tensegrity lattices are just $$text {sech}^2$$ -solitary (dark) waves 张力网格上的稀释脉冲只是$text {sech}^2$ -solitary(暗)波
IF 2.7 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-19 DOI: 10.1007/s11012-024-01853-8
Julia de Castro Motta, Fernando Fraternali, Giuseppe Saccomandi

This study investigates the propagation of rarefaction solitary waves in one-dimensional, tensegrity-like mass-spring lattices that are subject to an initial state of pre-compression. The analyzed systems exhibit a cubic interaction potential between adjacent masses that accurately captures the constitutive response of tensegrity prisms with elastically softening behavior. Analytical results are presented for the propagation of rarefaction solitary waves that produce a reduction of the initial prestress exhibited by the system. It is known in the literature that the use of cubic interaction potentials in one-dimensional lattices enables the prediction of the propagation of solitary waves with sech(^2) profile. Investigating the particular case of pre-compressed, softening-type tensegrity lattices, this study shows that such a noticeable result can be derived using both the classical and the improved Boussinesq equation. The given results reveal the presence of rarefaction solitary waves in a suitable range of wave speeds, and offer an explicit formula for the upper bound of the rarefaction wave speed that leaves the system in a compressed state. The outcomes of the present work pave the way to the development of analytic models for the design of radically new, metamaterial-type impact protection systems. Numerical simulations show the ability of the tensegrity-like model in predicting the propagation of rarefaction solitary waves in a physical model of a tensegrity mass-spring chain.

本研究探讨了稀释孤波在一维张拉网格状质量弹簧网格中的传播,这些网格处于预压缩的初始状态。所分析的系统显示了相邻质量之间的立方相互作用势,准确捕捉到了具有弹性软化行为的张弦棱柱的构成响应。本文给出了稀释孤波传播的分析结果,稀释孤波会降低系统的初始预应力。文献指出,在一维晶格中使用立方相互作用势可以预测具有 sech(^2) 轮廓的孤波传播。本研究通过对预压软化型张弦格构的特殊情况进行研究,表明使用经典的和改进的布森斯克方程都可以得出这样一个明显的结果。所给出的结果揭示了在适当的波速范围内稀释孤波的存在,并提供了使系统处于压缩状态的稀释波速上限的明确公式。本研究成果为设计全新的超材料型冲击防护系统的分析模型的开发铺平了道路。数值模拟显示了类张弦模型预测稀释孤波在张弦质量弹簧链物理模型中传播的能力。
{"title":"Rarefaction pulses on tensegrity lattices are just $$text {sech}^2$$ -solitary (dark) waves","authors":"Julia de Castro Motta, Fernando Fraternali, Giuseppe Saccomandi","doi":"10.1007/s11012-024-01853-8","DOIUrl":"https://doi.org/10.1007/s11012-024-01853-8","url":null,"abstract":"<p>This study investigates the propagation of rarefaction solitary waves in one-dimensional, tensegrity-like mass-spring lattices that are subject to an initial state of pre-compression. The analyzed systems exhibit a cubic interaction potential between adjacent masses that accurately captures the constitutive response of tensegrity prisms with elastically softening behavior. Analytical results are presented for the propagation of rarefaction solitary waves that produce a reduction of the initial prestress exhibited by the system. It is known in the literature that the use of cubic interaction potentials in one-dimensional lattices enables the prediction of the propagation of solitary waves with sech<span>(^2)</span> profile. Investigating the particular case of pre-compressed, softening-type tensegrity lattices, this study shows that such a noticeable result can be derived using both the classical and the improved Boussinesq equation. The given results reveal the presence of rarefaction solitary waves in a suitable range of wave speeds, and offer an explicit formula for the upper bound of the rarefaction wave speed that leaves the system in a compressed state. The outcomes of the present work pave the way to the development of analytic models for the design of radically new, metamaterial-type impact protection systems. Numerical simulations show the ability of the tensegrity-like model in predicting the propagation of rarefaction solitary waves in a physical model of a tensegrity mass-spring chain.</p>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"21 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141745723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Dynamic stability and vibration isolation property of a foot-leg coupling bio-inspired vibration isolation structure 脚腿耦合生物启发隔振结构的动态稳定性和隔振性能
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-19 DOI: 10.1007/s11012-024-01858-3
Shihua Zhou, Pengyang Wang, Yunchao Zhou, Chenhui Zhou, Zichun Zhou, XinHai Yu

Inspired that Kangaroo could buffer the shock and vibration from ground and keep the body and head steady and low/wide-frequency vibration isolation performance, a novel foot-leg coupling bio-inspired vibration isolation (FLBVI) system is proposed considering the synergy among skeleton, ligament/muscle and articulation. Based on the statics model, the static properties are investigated, and the idealized loading capacity and quasi-zero stiffness (QZS) range could be easily obtained by adjusting structure parameters. Combining with the dynamic model, the dynamic equation of the FLBVI structure is derived by Lagrange principle, and the nonlinear properties are analyzed by incremental harmonic balance method (IHBM). Based on verifying validity and feasibility of theoretical model with experiment results, the dynamic behaviors and vibration isolation performances of FLBVI structure are revealed from the visual angle of resonance characteristic and displacement transmissibility under different parameters. The results show that the FLBVI could availably reduce response amplitude, broaden the vibration isolation bandwidth, and then improve vibration isolation performance (below 5 Hz) and stability with proper parameters. The research of the FLBVI structure provides an innovative strategy of the designing bio-inspired vibration isolation structure.

受袋鼠能缓冲来自地面的冲击和振动并保持身体和头部稳定以及低/宽频隔振性能的启发,考虑到骨骼、韧带/肌肉和关节之间的协同作用,提出了一种新型足腿耦合生物启发隔振(FLBVI)系统。在静力学模型的基础上,对其静态特性进行了研究,并通过调整结构参数轻松获得了理想化的负载能力和准零刚度(QZS)范围。结合动力模型,利用拉格朗日原理推导出了 FLBVI 结构的动力方程,并利用增量谐波平衡法(IHBM)分析了其非线性特性。在利用实验结果验证理论模型有效性和可行性的基础上,从不同参数下的共振特性视角和位移传递率揭示了 FLBVI 结构的动力学行为和隔振性能。结果表明,FLBVI 可以有效降低响应振幅,拓宽隔振带宽,并在参数合适的情况下提高隔振性能(5 Hz 以下)和稳定性。FLBVI 结构的研究为生物启发隔振结构的设计提供了一种创新策略。
{"title":"Dynamic stability and vibration isolation property of a foot-leg coupling bio-inspired vibration isolation structure","authors":"Shihua Zhou,&nbsp;Pengyang Wang,&nbsp;Yunchao Zhou,&nbsp;Chenhui Zhou,&nbsp;Zichun Zhou,&nbsp;XinHai Yu","doi":"10.1007/s11012-024-01858-3","DOIUrl":"10.1007/s11012-024-01858-3","url":null,"abstract":"<div><p>Inspired that Kangaroo could buffer the shock and vibration from ground and keep the body and head steady and low/wide-frequency vibration isolation performance, a novel foot-leg coupling bio-inspired vibration isolation (FLBVI) system is proposed considering the synergy among skeleton, ligament/muscle and articulation. Based on the statics model, the static properties are investigated, and the idealized loading capacity and quasi-zero stiffness (QZS) range could be easily obtained by adjusting structure parameters. Combining with the dynamic model, the dynamic equation of the FLBVI structure is derived by Lagrange principle, and the nonlinear properties are analyzed by incremental harmonic balance method (IHBM). Based on verifying validity and feasibility of theoretical model with experiment results, the dynamic behaviors and vibration isolation performances of FLBVI structure are revealed from the visual angle of resonance characteristic and displacement transmissibility under different parameters. The results show that the FLBVI could availably reduce response amplitude, broaden the vibration isolation bandwidth, and then improve vibration isolation performance (below 5 Hz) and stability with proper parameters. The research of the FLBVI structure provides an innovative strategy of the designing bio-inspired vibration isolation structure.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 9","pages":"1499 - 1515"},"PeriodicalIF":1.9,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141745722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A computed tomography-based limit analysis approach to investigate the mechanical behavior of the human femur prone to fracture 用基于计算机断层扫描的极限分析方法研究易骨折人体股骨的力学行为
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-17 DOI: 10.1007/s11012-024-01850-x
Cristina Falcinelli, Aurora Angela Pisano, Marcello Vasta, Paolo Fuschi

The paper proposes a refined CT-based FE modelling strategy that implements a limit analysis numerical procedure, namely the Elastic Compensation Method (ECM), to estimate a lower bound to the collapse load of a human femur. In particular, the model geometry was obtained from CT images by segmentation of a fresh-frozen human cadaveric femur that was discretized with second-order tetrahedral 3D finite elements. A yield criterion of Tsai–Wu-type, expressed in principal stress space, was adopted to model the bone tissues for which the strength limit values in tension, compression and shear are computed locally from the femoral density distribution also derived from CT images. The developed CT-based numerical technique showed the ability to predict, at least for the examined femur for which the experimental collapse load is available, a lower bound to the collapse load. The proposed approach seems a promising and effective tool that could be adopted into clinical practice to predict the fracture risk of human femur starting from patient-specific data given by medical imaging.

本文提出了一种基于 CT 的精细有限元建模策略,该策略实施了一种极限分析数值程序,即弹性补偿法 (ECM),用于估算人体股骨塌陷载荷的下限。具体而言,模型的几何形状是通过对新鲜冷冻的人体尸体股骨进行分割,并用二阶四面体三维有限元离散化后从 CT 图像中获得的。模型中的骨组织采用了以主应力空间表示的蔡武型屈服准则,其拉伸、压缩和剪切强度极限值是根据同样从 CT 图像中获得的股骨密度分布局部计算得出的。所开发的基于 CT 的数值技术表明,至少对于有实验性塌陷载荷的受检股骨而言,它能够预测塌陷载荷的下限。所提出的方法似乎是一种很有前途的有效工具,可用于临床实践,从医学影像提供的患者特定数据出发,预测人体股骨的骨折风险。
{"title":"A computed tomography-based limit analysis approach to investigate the mechanical behavior of the human femur prone to fracture","authors":"Cristina Falcinelli,&nbsp;Aurora Angela Pisano,&nbsp;Marcello Vasta,&nbsp;Paolo Fuschi","doi":"10.1007/s11012-024-01850-x","DOIUrl":"10.1007/s11012-024-01850-x","url":null,"abstract":"<div><p>The paper proposes a refined CT-based FE modelling strategy that implements a limit analysis numerical procedure, namely the Elastic Compensation Method (ECM), to estimate a lower bound to the collapse load of a human femur. In particular, the model geometry was obtained from CT images by segmentation of a fresh-frozen human cadaveric femur that was discretized with second-order tetrahedral 3D finite elements. A yield criterion of Tsai–Wu-type, expressed in principal stress space, was adopted to model the bone tissues for which the strength limit values in tension, compression and shear are computed locally from the femoral density distribution also derived from CT images. The developed CT-based numerical technique showed the ability to predict, at least for the examined femur for which the experimental collapse load is available, a lower bound to the collapse load. The proposed approach seems a promising and effective tool that could be adopted into clinical practice to predict the fracture risk of human femur starting from patient-specific data given by medical imaging.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 8","pages":"1301 - 1313"},"PeriodicalIF":1.9,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11012-024-01850-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141829995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fluid–solid coupling analysis of the whole spiral organ of Corti 柯蒂氏整个螺旋器官的流固耦合分析
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-17 DOI: 10.1007/s11012-024-01761-x
Jiakun Wang, Junyi Liang, Bin Liu, Wenjuan Yao

The complex fluid–solid coupling movement of macro–micro structures and lymphatic fluid in the cochlea plays a crucial role in the mechanism of sound perception in the human ear. However, previous studies have primarily focused on the macrostructure and overlooked the microstructure of the Organ of Corti (OC). In reality, the microstructure of the OC can regulate the vibration of the basilar membrane, which is important for sound perception. To address this, a three-dimensional spiral passive cochlear model containing a complete OC that conforms to the real physiology of the human ear was developed, but the significant amplification of its motion by the action of outer hair cells (OHC) in the living cochlea was not considered. The fluid–solid coupling calculations were conducted on this model, specifically examining the mechanical response of the OC microstructure and the pressure changes in the lymphatic fluid. The results showed that the lower stiffness structure in the OC has a lower stress level, which contributes to the realization of sound perception. As the frequencies increases, the region of peak stress and displacement in the OHC moves from the apex to the base of the cochlea, reflecting frequency-selective characteristics. The tunnel of the OC amplifies pressure waves at specific locations, enabling more accurate frequency recognition. Furthermore, the presence of the OC not only causes significant radial differences in lymphatic fluid pressure in the scala vestibule, but also enhances internal cochlear vibration, playing an undeniable regulatory role in the sound perception.Kindly check and verify edit made in article title.We have checked and verified the editing in the article title.

耳蜗中的宏微观结构和淋巴液的复杂流固耦合运动在人耳的声音感知机制中起着至关重要的作用。然而,以往的研究主要关注宏观结构,而忽视了蜗管(OC)的微观结构。实际上,OC 的微观结构可以调节基底膜的振动,而基底膜的振动对声音感知非常重要。为了解决这个问题,我们开发了一个三维螺旋被动耳蜗模型,其中包含一个符合人耳真实生理结构的完整 OC,但没有考虑活体耳蜗中外毛细胞(OHC)对其运动的显著放大作用。对该模型进行了流固耦合计算,特别研究了 OC 微观结构的机械响应和淋巴液的压力变化。结果表明,OC 中的低刚度结构具有较低的应力水平,有助于实现声音感知。随着频率的增加,OHC 中的应力和位移峰值区域从耳蜗顶端移动到底部,这反映了频率选择性特征。OC 隧道会放大特定位置的压力波,从而实现更准确的频率识别。此外,OC 的存在不仅会导致前庭淋巴液压力出现明显的径向差异,还会增强耳蜗内部的振动,对声音感知起到不可否认的调节作用。
{"title":"Fluid–solid coupling analysis of the whole spiral organ of Corti","authors":"Jiakun Wang,&nbsp;Junyi Liang,&nbsp;Bin Liu,&nbsp;Wenjuan Yao","doi":"10.1007/s11012-024-01761-x","DOIUrl":"10.1007/s11012-024-01761-x","url":null,"abstract":"<div><p>The complex fluid–solid coupling movement of macro–micro structures and lymphatic fluid in the cochlea plays a crucial role in the mechanism of sound perception in the human ear. However, previous studies have primarily focused on the macrostructure and overlooked the microstructure of the Organ of Corti (OC). In reality, the microstructure of the OC can regulate the vibration of the basilar membrane, which is important for sound perception. To address this, a three-dimensional spiral passive cochlear model containing a complete OC that conforms to the real physiology of the human ear was developed, but the significant amplification of its motion by the action of outer hair cells (OHC) in the living cochlea was not considered. The fluid–solid coupling calculations were conducted on this model, specifically examining the mechanical response of the OC microstructure and the pressure changes in the lymphatic fluid. The results showed that the lower stiffness structure in the OC has a lower stress level, which contributes to the realization of sound perception. As the frequencies increases, the region of peak stress and displacement in the OHC moves from the apex to the base of the cochlea, reflecting frequency-selective characteristics. The tunnel of the OC amplifies pressure waves at specific locations, enabling more accurate frequency recognition. Furthermore, the presence of the OC not only causes significant radial differences in lymphatic fluid pressure in the scala vestibule, but also enhances internal cochlear vibration, playing an undeniable regulatory role in the sound perception.Kindly check and verify edit made in article title.We have checked and verified the editing in the article title.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 9","pages":"1465 - 1479"},"PeriodicalIF":1.9,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141829936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A novel method of reconstructing planar flow field from given distribution of single velocity component: comparison to conventional divergence-free approach 从给定的单一速度分量分布重建平面流场的新方法:与传统无发散方法的比较
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-17 DOI: 10.1007/s11012-024-01771-9
Kenjiro Shimano, Suguru Shiratori, Hideaki Nagano

Measurements of a single flow velocity component are still prevalent due to their reasonable costs and some difficulties in multiple-component measurements. If the transverse component can be obtained additionally by a numerical technique, qualitative features of the flow will be understood more effectively. In this context, methods based on the 2-dimensonal divergence-free assumption have been widely used for problems in which a single velocity component is measured over a planar domain. In this study, the authors proposed a method of approximating the second planar velocity component by minimising an objective function expressed with divergence and vorticity so that the mass transport in the out-of-plane direction could be taken into consideration. The present method was tested with numerically produced 3-dimensional flows in a hexahedral chamber and a flow around a bluff body measured by particle image velocimetry. There was a tendency that the present method calculated the second velocity component with smaller errors than existing divergence-free approaches. It was also shown that the present method had a high capability to locate strong suction and generation caused by the mass transport in the out-of-plane direction. The present method is deemed promising for many one-component flow measurements in engineering and medicine.

由于单流速分量测量成本合理,而多分量测量存在一些困难,因此单流速分量测量仍很普遍。如果能通过数值技术额外获得横向分量,就能更有效地了解流动的定性特征。在这种情况下,基于二维无发散假设的方法已被广泛用于测量平面域上单一速度分量的问题。在这项研究中,作者提出了一种通过最小化用发散和涡度表示的目标函数来逼近第二个平面速度分量的方法,从而将平面外方向的质量传输考虑在内。本方法通过六面体室中的三维流动和粒子图像测速仪测量的崖体周围的流动进行了测试。与现有的无发散方法相比,本方法计算第二速度分量的误差更小。研究还表明,本方法具有很强的定位能力,可以定位由平面外方向的质量输运引起的强吸力和生成力。本方法有望用于工程和医学领域的许多单分量流动测量。
{"title":"A novel method of reconstructing planar flow field from given distribution of single velocity component: comparison to conventional divergence-free approach","authors":"Kenjiro Shimano,&nbsp;Suguru Shiratori,&nbsp;Hideaki Nagano","doi":"10.1007/s11012-024-01771-9","DOIUrl":"10.1007/s11012-024-01771-9","url":null,"abstract":"<div><p>Measurements of a single flow velocity component are still prevalent due to their reasonable costs and some difficulties in multiple-component measurements. If the transverse component can be obtained additionally by a numerical technique, qualitative features of the flow will be understood more effectively. In this context, methods based on the 2-dimensonal divergence-free assumption have been widely used for problems in which a single velocity component is measured over a planar domain. In this study, the authors proposed a method of approximating the second planar velocity component by minimising an objective function expressed with divergence and vorticity so that the mass transport in the out-of-plane direction could be taken into consideration. The present method was tested with numerically produced 3-dimensional flows in a hexahedral chamber and a flow around a bluff body measured by particle image velocimetry. There was a tendency that the present method calculated the second velocity component with smaller errors than existing divergence-free approaches. It was also shown that the present method had a high capability to locate strong suction and generation caused by the mass transport in the out-of-plane direction. The present method is deemed promising for many one-component flow measurements in engineering and medicine.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 7","pages":"1191 - 1227"},"PeriodicalIF":1.9,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11012-024-01771-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141830023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Structural response of half-scale pumice concrete masonry building: shake table/ambient vibration tests and FE analysis 半比例浮石混凝土砌体建筑的结构响应:振动台/环境振动试验和有限元分析
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-08 DOI: 10.1007/s11012-024-01849-4
Ali Kaya, Boudjamaa Roudane, Süleyman Adanur, Fezayil Sunca, Ali Fuat Genç, Murat Gunaydin, Ahmet Can Altunişik

Seismic performance evaluation of masonry structures is of paramount importance for ensuring the safety and resilience of buildings in earthquake-prone regions. There are limited number of studies on pumice elements in the literature. In addition, there are almost no studies investigating the earthquake behavior of pumice masonry building as a whole structure. In this context, a comprehensive understanding of their seismic response and dynamic characteristics has been lacking. To address this knowledge gap, a shake-table experimental campaign was undertaken, wherein half-scale pumice masonry building was exposed to simulated seismic forces. To enhance the experimental findings, numerical simulations were performed to confirm and expand our comprehension of how the pumice masonry structure responds to dynamic forces. Integrating both experimental and numerical outcomes provides a holistic understanding of how pumice masonry buildings behave during seismic events. At the end of the experimental study, the frequency values of the pumice model were observed to decrease up to 23.5% in the modes compared to the undamaged state. In the numerical model, this value decreases up to 19.85%. For the undamaged and damaged model, the first three experimental mode shapes were similar to the numerical mode shapes. Both experimental and numerical results show that the expected damages occur in the same regions. These results show that nonlinear FE models can be helpful in determining potential damage model locations. The findings have implications for the seismic design and retrofitting of similar traditional masonry buildings, facilitating the development of resilient and sustainable engineering solutions in seismic-prone regions.

砌体结构的抗震性能评估对于确保地震多发地区建筑物的安全和抗震能力至关重要。文献中关于浮石构件的研究数量有限。此外,将浮石砌体建筑作为一个整体结构来研究其地震行为的研究几乎为零。在这种情况下,对其地震响应和动态特性缺乏全面的了解。针对这一知识空白,我们开展了一项振动台实验活动,将半比例浮石砌体建筑暴露在模拟地震力下。为了加强实验结果,还进行了数值模拟,以确认和扩展我们对浮石砌体结构如何对动态力做出反应的理解。综合实验和数值结果,我们可以全面了解浮石砌体建筑在地震事件中的表现。实验研究结束时,观察到浮石模型的频率值与未损坏状态相比降低了 23.5%。在数值模型中,这一数值降低了 19.85%。对于未损坏和损坏模型,前三个实验模态振型与数值模态振型相似。实验和数值结果都表明,预期的损坏发生在相同的区域。这些结果表明,非线性 FE 模型有助于确定潜在的破坏模型位置。这些研究结果对类似传统砌体建筑的抗震设计和改造具有借鉴意义,有助于在地震多发地区开发具有抗震能力的可持续工程解决方案。
{"title":"Structural response of half-scale pumice concrete masonry building: shake table/ambient vibration tests and FE analysis","authors":"Ali Kaya,&nbsp;Boudjamaa Roudane,&nbsp;Süleyman Adanur,&nbsp;Fezayil Sunca,&nbsp;Ali Fuat Genç,&nbsp;Murat Gunaydin,&nbsp;Ahmet Can Altunişik","doi":"10.1007/s11012-024-01849-4","DOIUrl":"10.1007/s11012-024-01849-4","url":null,"abstract":"<div><p>Seismic performance evaluation of masonry structures is of paramount importance for ensuring the safety and resilience of buildings in earthquake-prone regions. There are limited number of studies on pumice elements in the literature. In addition, there are almost no studies investigating the earthquake behavior of pumice masonry building as a whole structure. In this context, a comprehensive understanding of their seismic response and dynamic characteristics has been lacking. To address this knowledge gap, a shake-table experimental campaign was undertaken, wherein half-scale pumice masonry building was exposed to simulated seismic forces. To enhance the experimental findings, numerical simulations were performed to confirm and expand our comprehension of how the pumice masonry structure responds to dynamic forces. Integrating both experimental and numerical outcomes provides a holistic understanding of how pumice masonry buildings behave during seismic events. At the end of the experimental study, the frequency values of the pumice model were observed to decrease up to 23.5% in the modes compared to the undamaged state. In the numerical model, this value decreases up to 19.85%. For the undamaged and damaged model, the first three experimental mode shapes were similar to the numerical mode shapes. Both experimental and numerical results show that the expected damages occur in the same regions. These results show that nonlinear FE models can be helpful in determining potential damage model locations. The findings have implications for the seismic design and retrofitting of similar traditional masonry buildings, facilitating the development of resilient and sustainable engineering solutions in seismic-prone regions.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 7","pages":"1159 - 1190"},"PeriodicalIF":1.9,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11012-024-01849-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimal design of inerter-based absorbers with amplified inertance: from the improved tuned liquid column damper inerter (ITLCDI) to the improved tuned mass damper inerter (ITMDI) and improved tuned inerter damper (ITID) 具有放大惰性的基于阻尼器的吸收器的优化设计:从改进型调谐液柱阻尼器阻尼器 (ITLCDI) 到改进型调谐质量阻尼器阻尼器 (ITMDI) 和改进型调谐阻尼器阻尼器 (ITID)
IF 2.7 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-07 DOI: 10.1007/s11012-024-01834-x
Chiara Masnata, Antonina Pirrotta

This paper presents the optimal design of improved inerter-based absorbers to effectively mitigate vibrations in structural systems. The improvement of the inerter is achieved by integrating it within a rhombus truss, composed of rigid rods interconnected by hinges. This arrangement exploits the geometrical amplification effect to enhance inertial properties, thus leading to superior control performance. Specifically, both ends of the inerter are anchored to opposite points along one diagonal of the rhombus, while along the other diagonal, one end is grounded, and the other is linked to the structural system itself or other mechanical systems. The motion of these systems triggers the activation of the inerter, contributing to vibration dissipation. Previous studies have combined this improved inerter with a spring-dashpot unit proposing the so-called Improved Tuned Inerter Damper (ITID). Extending prior research, this study integrates the improved inerter with common passive control devices, such as the Tuned Liquid Column Damper (TLCD) and Tuned Mass Damper (TMD), resulting in the development of the novel Improved Tuned Liquid Column Damper Inerters (ITLCDI) and Improved Tuned Mass Damper Inerter (ITMDI). The optimal calibration for the ITLCDI through an analytical approach is presented, assuming stochastic processes for modeling seismic actions. Furthermore, it discusses how the ITLCDI configuration can be adapted to yield the ITMDI and ITID configurations, providing closed-form solutions for all three absorbers. Validation of the proposed method is performed through numerical simulations, with a thorough analysis conducted to assess the effectiveness of the ITLCDI relative to the ITMDI and ITID configurations.

本文介绍了改进型感应器吸收器的优化设计,以有效缓解结构系统中的振动。吸收器的改进是通过将其集成在菱形桁架内实现的,菱形桁架由通过铰链相互连接的刚性杆组成。这种布置方式利用了几何放大效应来增强惯性特性,从而实现卓越的控制性能。具体来说,惯性体的两端沿菱形的一条对角线固定在相对的点上,而沿另一条对角线,一端接地,另一端与结构系统本身或其他机械系统相连。这些系统的运动会触发阻尼器的启动,从而起到消振作用。之前的研究将这种改进型阻尼器与弹簧-底盘装置相结合,提出了所谓的改进型调谐阻尼器(ITID)。本研究对之前的研究进行了扩展,将改进型阻尼器与常见的被动控制装置(如调谐液柱阻尼器 (TLCD) 和调谐质量阻尼器 (TMD))相结合,开发出新型改进型调谐液柱阻尼器阻尼器 (ITLCDI) 和改进型调谐质量阻尼器阻尼器 (ITMDI)。报告介绍了通过分析方法对 ITLCDI 进行优化校准的情况,并假设了地震作用建模的随机过程。此外,报告还讨论了如何调整 ITLCDI 配置以生成 ITMDI 和 ITID 配置,并为所有三个吸收器提供闭式解决方案。通过数值模拟对提出的方法进行了验证,并进行了全面分析,以评估 ITLCDI 相对于 ITMDI 和 ITID 配置的有效性。
{"title":"Optimal design of inerter-based absorbers with amplified inertance: from the improved tuned liquid column damper inerter (ITLCDI) to the improved tuned mass damper inerter (ITMDI) and improved tuned inerter damper (ITID)","authors":"Chiara Masnata, Antonina Pirrotta","doi":"10.1007/s11012-024-01834-x","DOIUrl":"https://doi.org/10.1007/s11012-024-01834-x","url":null,"abstract":"<p>This paper presents the optimal design of improved inerter-based absorbers to effectively mitigate vibrations in structural systems. The improvement of the inerter is achieved by integrating it within a rhombus truss, composed of rigid rods interconnected by hinges. This arrangement exploits the geometrical amplification effect to enhance inertial properties, thus leading to superior control performance. Specifically, both ends of the inerter are anchored to opposite points along one diagonal of the rhombus, while along the other diagonal, one end is grounded, and the other is linked to the structural system itself or other mechanical systems. The motion of these systems triggers the activation of the inerter, contributing to vibration dissipation. Previous studies have combined this improved inerter with a spring-dashpot unit proposing the so-called Improved Tuned Inerter Damper (ITID). Extending prior research, this study integrates the improved inerter with common passive control devices, such as the Tuned Liquid Column Damper (TLCD) and Tuned Mass Damper (TMD), resulting in the development of the novel Improved Tuned Liquid Column Damper Inerters (ITLCDI) and Improved Tuned Mass Damper Inerter (ITMDI). The optimal calibration for the ITLCDI through an analytical approach is presented, assuming stochastic processes for modeling seismic actions. Furthermore, it discusses how the ITLCDI configuration can be adapted to yield the ITMDI and ITID configurations, providing closed-form solutions for all three absorbers. Validation of the proposed method is performed through numerical simulations, with a thorough analysis conducted to assess the effectiveness of the ITLCDI relative to the ITMDI and ITID configurations.</p>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"23 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141546364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Chaotic dynamics of a continuous and discrete generalized Ziegler pendulum 连续和离散广义齐格勒摆的混沌动力学
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-05 DOI: 10.1007/s11012-024-01848-5
Stefano Disca, Vincenzo Coscia

We present analytical and numerical results on integrability and transition to chaotic motion for a generalized Ziegler pendulum, a double pendulum subject to an angular elastic potential and a follower force. Several variants of the original dynamical system, including the presence of gravity and friction, are considered, in order to analyze whether the integrable cases are preserved or not in presence of further external forces, both potential and non-potential. Particular attention is devoted to the presence of dissipative forces, that are analyzed in two different formulations. Furthermore, a study of the discrete version is performed. The analysis of periodic points, that is presented up to period 3, suggests that the discrete map associated to the dynamical system has not dense sets of periodic points, so that the map would not be chaotic in the sense of Devaney for a choice of the parameters that corresponds to a general case of chaotic motion for the original system.

我们提出了关于广义齐格勒摆(受角弹性势和随动力作用的双摆)的可整性和向混沌运动过渡的分析和数值结果。考虑了原始动力系统的几种变体,包括重力和摩擦力的存在,以分析在进一步的外力(包括势能和非势能)存在时,可积分情况是否保留。特别关注了耗散力的存在,并用两种不同的公式对其进行了分析。此外,还对离散版本进行了研究。直到周期 3 的周期点分析表明,与动力系统相关的离散映射没有密集的周期点集,因此,对于与原始系统的一般混沌运动情况相对应的参数选择,映射不会是 Devaney 意义上的混沌。
{"title":"Chaotic dynamics of a continuous and discrete generalized Ziegler pendulum","authors":"Stefano Disca,&nbsp;Vincenzo Coscia","doi":"10.1007/s11012-024-01848-5","DOIUrl":"10.1007/s11012-024-01848-5","url":null,"abstract":"<div><p>We present analytical and numerical results on integrability and transition to chaotic motion for a generalized Ziegler pendulum, a double pendulum subject to an angular elastic potential and a follower force. Several variants of the original dynamical system, including the presence of gravity and friction, are considered, in order to analyze whether the integrable cases are preserved or not in presence of further external forces, both potential and non-potential. Particular attention is devoted to the presence of dissipative forces, that are analyzed in two different formulations. Furthermore, a study of the discrete version is performed. The analysis of periodic points, that is presented up to period 3, suggests that the discrete map associated to the dynamical system has not dense sets of periodic points, so that the map would not be chaotic in the sense of Devaney for a choice of the parameters that corresponds to a general case of chaotic motion for the original system.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 7","pages":"1139 - 1157"},"PeriodicalIF":1.9,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11012-024-01848-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Active design method and performance prediction of internal gear pairs with low sliding ratio 低滑动比内齿轮副的主动设计方法和性能预测
IF 1.9 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-04 DOI: 10.1007/s11012-024-01845-8
Wei Sheng, Zhengminqing Li, Xiaofeng Yu, Rongsheng Xi

Reducing relative sliding between tooth surfaces contributes to the improved reliability of gear operation. This paper presents an active design of an internal gear drive with low sliding ratio (LSR). In order to achieve a lower sliding ratio, the relationship between the sliding ratio and the contact path is established. The tooth profiles of the internal gear are determined based on a given contact path using a cubic function. Tooth interference issues arising during gear meshing and machining are systematically analyzed. Additionally, tooth profile features are illustrated through an example. The operating performance, including tooth strength and lubrication characteristics, is evaluated through a comparison with that of the traditional involute gear drive. Results indicate that the novel internal gear transmission exhibits excellent resistance to wear, bending, and lubrication performance. Finally, the rationality of the tooth profile design is validated through physical assembly.

减少齿面之间的相对滑动有助于提高齿轮运行的可靠性。本文介绍了低滑动比(LSR)内齿轮传动装置的主动设计。为了实现更低的滑动比,建立了滑动比与接触路径之间的关系。根据给定的接触路径,使用三次函数确定内齿轮的齿形。系统分析了齿轮啮合和加工过程中出现的齿干涉问题。此外,还通过实例说明了齿廓特征。通过与传统渐开线齿轮传动的比较,对包括齿强度和润滑特性在内的运行性能进行了评估。结果表明,新型内齿轮传动装置具有出色的抗磨损、抗弯曲和润滑性能。最后,通过物理装配验证了齿形设计的合理性。
{"title":"Active design method and performance prediction of internal gear pairs with low sliding ratio","authors":"Wei Sheng,&nbsp;Zhengminqing Li,&nbsp;Xiaofeng Yu,&nbsp;Rongsheng Xi","doi":"10.1007/s11012-024-01845-8","DOIUrl":"10.1007/s11012-024-01845-8","url":null,"abstract":"<div><p>Reducing relative sliding between tooth surfaces contributes to the improved reliability of gear operation. This paper presents an active design of an internal gear drive with low sliding ratio (LSR). In order to achieve a lower sliding ratio, the relationship between the sliding ratio and the contact path is established. The tooth profiles of the internal gear are determined based on a given contact path using a cubic function. Tooth interference issues arising during gear meshing and machining are systematically analyzed. Additionally, tooth profile features are illustrated through an example. The operating performance, including tooth strength and lubrication characteristics, is evaluated through a comparison with that of the traditional involute gear drive. Results indicate that the novel internal gear transmission exhibits excellent resistance to wear, bending, and lubrication performance. Finally, the rationality of the tooth profile design is validated through physical assembly.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"59 7","pages":"1121 - 1137"},"PeriodicalIF":1.9,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141546366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
CFD simulation of a Rushton turbine stirred-tank using open-source software with critical evaluation of MRF-based rotation modeling 使用开源软件对 Rushton 涡轮搅拌罐进行 CFD 模拟,并对基于 MRF 的旋转建模进行重要评估
IF 2.7 3区 工程技术 Q3 MECHANICS Pub Date : 2024-07-03 DOI: 10.1007/s11012-024-01824-z
Alfred Reid, Riccardo Rossi, Ciro Cottini, Andrea Benassi

A critical evaluation of the impact of the Multiple Reference Frame (MRF) technique on steady RANS simulations of a Rushton turbine stirred-tank is presented. The analysis, based on the open-source software OpenFOAM, is focused on the choice of the diameter and thickness of the MRF region and on their effect on the predicted velocity field and mixing times in the tank. Five diameters of the MRF region are compared for the same operating conditions of the turbine, showing limited differences in velocity profiles, which are found in general good agreement with available experimental data. Significant differences are nonetheless found in the predicted levels of turbulence intensity within the tank, with a considerable amount of artificially generated turbulence at the boundary of the MRF region for the largest diameters. The impact of the different predictions of the turbulent field on the modeling of the mixing process in the tank is evaluated by simulating the release of a passive scalar, using the frozen-flow field hypothesis. The results show changes in mixing times up to a factor of three when comparing MRF regions of different sizes. Thus, the present investigation highlights the importance of assessing the effect of the MRF zone size on numerical results as a standard practice in RANS based simulations of stirred-tanks.

本文对多参考框架(MRF)技术对 Rushton 涡轮搅拌槽稳定 RANS 模拟的影响进行了批判性评估。分析以开源软件 OpenFOAM 为基础,重点关注 MRF 区域直径和厚度的选择及其对预测速度场和搅拌罐内混合时间的影响。在涡轮机工作条件相同的情况下,对 MRF 区域的五种直径进行了比较,结果显示速度曲线的差异有限,与现有实验数据基本吻合。然而,水箱内湍流强度的预测水平存在显著差异,最大直径的 MRF 区域边界处存在大量人工产生的湍流。利用冻结流场假设,通过模拟被动标量的释放,评估了湍流场的不同预测对水槽内混合过程建模的影响。结果表明,在比较不同大小的 MRF 区域时,混合时间的变化可达三倍。因此,本研究强调了在基于 RANS 的搅拌罐模拟中,评估 MRF 区域大小对数值结果影响的重要性。
{"title":"CFD simulation of a Rushton turbine stirred-tank using open-source software with critical evaluation of MRF-based rotation modeling","authors":"Alfred Reid, Riccardo Rossi, Ciro Cottini, Andrea Benassi","doi":"10.1007/s11012-024-01824-z","DOIUrl":"https://doi.org/10.1007/s11012-024-01824-z","url":null,"abstract":"<p>A critical evaluation of the impact of the Multiple Reference Frame (MRF) technique on steady RANS simulations of a Rushton turbine stirred-tank is presented. The analysis, based on the open-source software OpenFOAM, is focused on the choice of the diameter and thickness of the MRF region and on their effect on the predicted velocity field and mixing times in the tank. Five diameters of the MRF region are compared for the same operating conditions of the turbine, showing limited differences in velocity profiles, which are found in general good agreement with available experimental data. Significant differences are nonetheless found in the predicted levels of turbulence intensity within the tank, with a considerable amount of artificially generated turbulence at the boundary of the MRF region for the largest diameters. The impact of the different predictions of the turbulent field on the modeling of the mixing process in the tank is evaluated by simulating the release of a passive scalar, using the frozen-flow field hypothesis. The results show changes in mixing times up to a factor of three when comparing MRF regions of different sizes. Thus, the present investigation highlights the importance of assessing the effect of the MRF zone size on numerical results as a standard practice in RANS based simulations of stirred-tanks.</p>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":"20 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Meccanica
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1