Acta Mechanica Sinica最新文献_第6页

Boussinesq problem of a finite elastic layer with the surface effect 具有表面效应有限弹性层的Boussinesq问题

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-21 DOI: 10.1007/s10409-024-24352-x

Hui Wu (, ), Sha Xiao (, ), Zhilong Peng (, ), Ning Jia (, ), Shaohua Chen (, )

{"title":"Boussinesq problem of a finite elastic layer with the surface effect","authors":"Hui Wu \u0000 (, ), Sha Xiao \u0000 (, ), Zhilong Peng \u0000 (, ), Ning Jia \u0000 (, ), Shaohua Chen \u0000 (, )","doi":"10.1007/s10409-024-24352-x","DOIUrl":"10.1007/s10409-024-24352-x","url":null,"abstract":"<div><p>Both the thickness effect and surface effect should be important in nano-indentation behavior of coatings due to the finite thickness and small indentation size. As a basic solution, the two-dimensional Boussinesq problem of a finite elastic layer bonded to a rigid substrate is studied in this paper, employing the surface-energy-density-based elastic theory. The Airy stress function and Fourier integral transform methods are adopted to solve the problem. A nalytical solutions of both the stress and displacement fields are well achieved for a finite elastic layer under a concentrated force and a uniform pressure. Unlike the classical solutions, it is discovered that both the thickness effect and surface effect will show significant influences on the Boussinesq elastic behaviors. The surface effect would harden the finite elastic layer and induce a more uniformly distributing displacements and stresses. Only when the thickness is sufficiently large, the Boussinesq solution of an elastic half space may represent that of a finite elastic layer case. A generalized hardness is further defined to include the coupling effects of thickness and surface for the Boussinesq problem of a finite elastic layer. Such a study would assist in the design and property evaluation of coatings and micro-devices with layer-substrate structures.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 9","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Mass-spring system modelling for biplane membrane flapping wings 双翼膜扑翼质量-弹簧系统建模

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-21 DOI: 10.1007/s10409-024-24093-x

Anh Tuan Nguyen, Thanh Dong Pham, Vu Dan Thanh Le, Quoc Tru Vu, Jae-Hung Han, Sang-Woo Kim

引用次数: 0

Physics-informed neural networks for predicting velocity and pressure fields from wave elevation based on Boussinesq model 基于Boussinesq模型预测波高程速度和压力场的物理信息神经网络

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-20 DOI: 10.1007/s10409-024-24322-x

Yao Hong (, ), Zhaoxin Gong (, ), Hua Liu (, )

{"title":"Physics-informed neural networks for predicting velocity and pressure fields from wave elevation based on Boussinesq model","authors":"Yao Hong \u0000 (, ), Zhaoxin Gong \u0000 (, ), Hua Liu \u0000 (, )","doi":"10.1007/s10409-024-24322-x","DOIUrl":"10.1007/s10409-024-24322-x","url":null,"abstract":"<div><p>The task of achieving high-accuracy full-field reconstruction in the realm of water waves is widely acknowledged as a challenge, primarily due to the sparsity and incompleteness of data measurement in both temporal and spatial dimensions. We develop a full-field velocity and pressure reconstruction approach for non-linear water waves based on physics-informed neural networks from the free surface measurement. The fully non-linear highly dispersive Boussinesq model is integrated to reduce the training cost by representing the three dimensional water wave problems in the horizontal two-dimensional plane with the inherent velocity distribution along water depth. A series of test cases, including the solitary waves, fifth-order Stokes waves, standing waves, and superimposed waves, are employed to evaluate the performance of the algorithm. The proposed novel neural networks are capable of accurately reconstructing the flow fields even when assimilating the limited and sparse free surface deformation data, which facilitates the development of detecting the flow characteristics in real ocean waves.</p></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 9","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142913028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Contact between deformed rough surfaces 变形粗糙表面之间的接触

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-20 DOI: 10.1007/s10409-024-24905-x

Liao-Liang Ke

引用次数: 0

Experimental study on unsteady flow of hydraulic conveying of a single coarse particle through a 90° bend 单粒粗颗粒90°弯道水力输送不稳定流动试验研究

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-20 DOI: 10.1007/s10409-024-24339-x

Hui Cheng (, ), Hong Xiong (, ), Yuxiang Chen (, ), Hong Zhu (, ), Chunliang Yu (, ), Guodong Zheng (, ), Yiyang Xing (, )

{"title":"Experimental study on unsteady flow of hydraulic conveying of a single coarse particle through a 90° bend","authors":"Hui Cheng \u0000 (, ), Hong Xiong \u0000 (, ), Yuxiang Chen \u0000 (, ), Hong Zhu \u0000 (, ), Chunliang Yu \u0000 (, ), Guodong Zheng \u0000 (, ), Yiyang Xing \u0000 (, )","doi":"10.1007/s10409-024-24339-x","DOIUrl":"10.1007/s10409-024-24339-x","url":null,"abstract":"<div><p>Bends contribute to a flexible layout of pipeline system, but also lead to intensive energy costs due to the complex flow characteristic. This experimental study is conducted to investigate the impact of a single coarse particle on the flow field in a bend. The velocity profiles of fluid on the axial symmetry plane of the bend are measured using time-resolved particle image velocimetry. The flow structures are extracted using the proper orthogonal decomposition method. The results reveal that there is a shear-layer flow in the bend during the transportation. With the increase in particle size, the particle has a dominant influence on the flow energy distribution of the overall flow. The impact of particles on the first few energetic flows is mainly in the latter part of the transportation, both temporally and spatially. As the particle size decreases, the most energetic unsteady flow within the bend changes from the convective flow to the flow of the shear layer.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 5","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Buckling and post-buckling behavior of ideal and non-ideal FG-GPLRC beams in thermal environment 理想和非理想FG-GPLRC梁在热环境下的屈曲和后屈曲行为

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-20 DOI: 10.1007/s10409-024-24374-x

Wachirawit Songsuwan, Son Thai, Nuttawit Wattanasakulpong

{"title":"Buckling and post-buckling behavior of ideal and non-ideal FG-GPLRC beams in thermal environment","authors":"Wachirawit Songsuwan, Son Thai, Nuttawit Wattanasakulpong","doi":"10.1007/s10409-024-24374-x","DOIUrl":"10.1007/s10409-024-24374-x","url":null,"abstract":"<div><p>This investigation aims to analyze thermal buckling and post-buckling behavior of functionally graded graphene nanoplatelet-reinforced composite (FG-GPLRC) beams. The beams are classified into two types of ideal and non-ideal FG-GPLRC beams in which the ideal beams have smooth profiles of material distributions and another beams have layer-wise distributions of materials. The material profiles of the ideal beams are utilized as the controlling tracks for producing the material distributions of the non-ideal beams via a layer-to-layer integration technique. This technique confirms that the overall weight fraction of the materials is the same for both types of beams. The proposed models can be used to determine the material properties of the beams for further investigation on thermal buckling and post-buckling of the beams. Third-order shear deformation theory is employed to construct the energy equations of the problems, and then they are solved by the implementation of the Jacobi-Ritz method cooperating with the direct iteration procedure and Newton-Raphson technique. From our investigation, it can be disclosed that when non-ideal beams are created using ideal beams parabolic profile, the results differ significantly. However, the differences between the results of ideal and non-ideal beams can be eliminated by adding more layers.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 9","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

On the windward boundary layer transition over a hypersonic blunt cone with global stability analyses and experiments 高超声速钝锥迎风边界层转捩的全局稳定性分析与实验

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-20 DOI: 10.1007/s10409-024-24150-x

Kuo Chen (, ), Xiaohu Li (, ), Guohua Tu (, ), Bingbing Wan (, ), Bin Zhang (, ), Jianqiang Chen (, ), Jiufen Chen (, )

{"title":"On the windward boundary layer transition over a hypersonic blunt cone with global stability analyses and experiments","authors":"Kuo Chen \u0000 (, ), Xiaohu Li \u0000 (, ), Guohua Tu \u0000 (, ), Bingbing Wan \u0000 (, ), Bin Zhang \u0000 (, ), Jianqiang Chen \u0000 (, ), Jiufen Chen \u0000 (, )","doi":"10.1007/s10409-024-24150-x","DOIUrl":"10.1007/s10409-024-24150-x","url":null,"abstract":"<div><p>This paper investigates the effect of the angle-of-attack (AOA) on the windward boundary-layer stability over a blunt cone with a nose radius of 5 mm. We consider a free-stream Mach number of 6 and a unit Reynolds number of 4.0 × 10<sup>7</sup> m<sup>−1</sup> and conduct both wind-tunnel experiments and stability analyses for AOAs ranging from 2°–10° at intervals of 2°. The results suggest that, as the AOA increases, the pressure gradient across the spanwise range becomes more pronounced, and the windward-side boundary layer becomes thinner. Using bi-global stability analysis, two unstable three-dimensional modes (varicose and sinuous) are identified in the windward boundary layer at various AOAs. The most unstable mode is the varicose V1 mode, in which the amplitude peak is initially close to the windward centerline and gradually shifts to the centerline downstream. Hence, the primary unstable disturbance exhibits a “V-like” distribution along the streamwise direction, which is likely to cause the V-shaped transition front observed in the wind-tunnel experiments. The eN method based on bi-global analysis is used to predict the transition location along the centerline on the windward region of the cone. The results indicate that, as the AOA increases, the transition location shifts forward, in line with our experimental results. Moreover, linear stability theory accurately predicts the eigenfunction and growth rate of the V1 mode obtained from bi-global analysis. This indicates that linear stability theory can be used to predict transitions in the windward boundary layer of a blunt cone at large AOAs under the conditions studied in this paper.</p></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 10","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Some fundamental issues in buoyancy-driven flows with implications for geophysical and astrophysical systems 浮力驱动流的一些基本问题及其对地球物理和天体物理系统的影响

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-15 DOI: 10.1007/s10409-024-24287-x

Ke-Qing Xia (, ), Kai Leong Chong (, ), Guang-Yu Ding (, ), Lu Zhang (, )

{"title":"Some fundamental issues in buoyancy-driven flows with implications for geophysical and astrophysical systems","authors":"Ke-Qing Xia \u0000 (, ), Kai Leong Chong \u0000 (, ), Guang-Yu Ding \u0000 (, ), Lu Zhang \u0000 (, )","doi":"10.1007/s10409-024-24287-x","DOIUrl":"10.1007/s10409-024-24287-x","url":null,"abstract":"<div><p>Buoyancy-driven flows are prevalent in a wide range of geophysical and astrophysical systems. In this review, we focus on three pivotal effects that significantly influence the dynamics and transport properties of buoyancy-driven flows and may have implications for natural systems. These effects pertain to the role of boundary conditions, the impact of rotation, and the effect of finite size. Boundary conditions represent how the fluid flow interacts with different kinds of surfaces. Rotation, as the Earth’s rotation in geophysical systems or the whirling of astrophysical systems, introduces Coriolis and centrifugal forces, leading to the profound vortical structure and distinct transport property. Finite size, representing geometrical constraints, influences the behavior of buoyancy-driven flows across varying geometrical settings. This review aims to provide a holistic understanding of the intricate interplay of these factors, offering insights into the complex natural phenomena from the perspectives of the three effects.</p></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142913022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Kalman filter based state estimation for the flexible multibody system described by ANCF 基于卡尔曼滤波器的 ANCF 柔性多体系统状态估计

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-13 DOI: 10.1007/s10409-024-24373-x

Zuqing Yu (, ), Shuaiyi Liu (, ), Qinglong Tian (, )

{"title":"Kalman filter based state estimation for the flexible multibody system described by ANCF","authors":"Zuqing Yu \u0000 (, ), Shuaiyi Liu \u0000 (, ), Qinglong Tian \u0000 (, )","doi":"10.1007/s10409-024-24373-x","DOIUrl":"10.1007/s10409-024-24373-x","url":null,"abstract":"<div><p>The state estimation of the flexible multibody systems is a vital issue since it is the base of effective control and condition monitoring. The research on the state estimation method of flexible multibody system with large deformation and large rotation remains rare. In this investigation, a state estimator based on multiple nonlinear Kalman filtering algorithms was designed for the flexible multibody systems containing large flexibility components that were discretized by absolute nodal coordinate formulation (ANCF). The state variable vector was constructed based on the independent coordinates which are identified through the constraint Jacobian. Three types of Kalman filters were used to compare their performance in the state estimation for ANCF. Three cases including flexible planar rotating beam, flexible four-bar mechanism, and flexible rotating shaft were employed to verify the proposed state estimator. According to the different performances of the three types of Kalman filter, suggestions were given for the construction of the state estimator for the flexible multibody system.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 5","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Asynchronous deployment scheme and multibody modeling of a ring-truss mesh reflector antenna 环形桁架网状反射天线的异步部署方案和多体建模

IF 3.8 2区工程技术

Acta Mechanica Sinica Pub Date : 2024-11-13 DOI: 10.1007/s10409-024-24147-x

Baiyan He (, ), Kangkang Li (, ), Lijun Jia (, ), Rui Nie (, ), Yesen Fan (, ), Guobiao Wang (, )

{"title":"Asynchronous deployment scheme and multibody modeling of a ring-truss mesh reflector antenna","authors":"Baiyan He \u0000 (, ), Kangkang Li \u0000 (, ), Lijun Jia \u0000 (, ), Rui Nie \u0000 (, ), Yesen Fan \u0000 (, ), Guobiao Wang \u0000 (, )","doi":"10.1007/s10409-024-24147-x","DOIUrl":"10.1007/s10409-024-24147-x","url":null,"abstract":"<div><p>Mesh reflector antennas are the mainstream of large space-borne antennas, and the stretching of the truss achieves their deployment. Currently, the truss is commonly designed to be a single degree of freedom (DOF) deployable mechanism with synchronization constraints. However, each deployable unit’s drive distribution and resistance load are uneven, and the forced synchronization constraints lead to the flexible deformation of rods and difficulties in the deployment scheme design. This paper introduces an asynchronous deployment scheme with a multi-DOF closed-chain deployable truss. The DOF of the truss is calculated, and the kinematic and dynamic models are established, considering the truss’s and cable net’s real-time coupling. An integrated solving algorithm for implicit differential-algebraic equations is proposed to solve the dynamic models. A prototype of a six-unit antenna was fabricated, and the experiment was carried out. The dynamic performances in synchronous and asynchronous deployment schemes are analyzed, and the results show that the cable resistance and truss kinetic energy impact under the asynchronous deployment scheme are minor, and the antenna is more straightforward to deploy. The work provides a new asynchronous deployment scheme and a universal antenna modeling method for dynamic design and performance improvement.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 5","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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