Zhiyuan Liu (, ), Yiqi Xiao (, ), Li Yang (, ), Wei Liu (, ), Gang Yan (, ), Yu Sun (, ), Yichun Zhou (, )
{"title":"Failure prediction of thermal barrier coatings on turbine blades under calcium-magnesium-alumina-silicate corrosion and thermal shock","authors":"Zhiyuan Liu \u0000 (, ), Yiqi Xiao \u0000 (, ), Li Yang \u0000 (, ), Wei Liu \u0000 (, ), Gang Yan \u0000 (, ), Yu Sun \u0000 (, ), Yichun Zhou \u0000 (, )","doi":"10.1007/s10409-024-24285-x","DOIUrl":"10.1007/s10409-024-24285-x","url":null,"abstract":"<div><p>Failure of thermal barrier coatings (TBCs) can reduce the safety of aero-engines. Predicting the lifetime of TBCs on turbine blades under real service conditions is challenging due to the complex multiscale computation required and the chemo-thermo-mechanically coupled mechanisms involved. This paper proposes a multiscale deep-learning method for TBC failure prediction under typical thermal shock conditions involving calcium-magnesium-alumina-silicate (CMAS) corrosion. A micro-scale model is used to describe local stress and damage with consideration of the TBC microstructure and CMAS infiltration and corrosion mechanisms. A deep learning network is developed to reveal the effect of microscale corrosion on TBC lifetime. The modeled spalling mechanism and area are consistent with the experimental results, with the predicted lifetime being within 20% of that observed. This work provides an effective method for predicting the lifetime of TBCs under real service conditions.\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":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579540","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}
Kandavkovi Mallikarjuna Nihaal, Ulavathi Shettar Mahabaleshwar, Dia Zeidan, Sang Woo Joo
{"title":"Impact of quadratic thermal radiation on MHD nanofluid flow across a stretching sheet with variable thickness: Xue and Yamado-Ota thermophysical model","authors":"Kandavkovi Mallikarjuna Nihaal, Ulavathi Shettar Mahabaleshwar, Dia Zeidan, Sang Woo Joo","doi":"10.1007/s10409-024-24405-x","DOIUrl":"10.1007/s10409-024-24405-x","url":null,"abstract":"<div><p>The work comparing the Yamada-Ota and Xue models for nanoparticle flow across a stretching surface has benefits in nanotechnology, medicinal treatments, environmental engineering, renewable energy, and heat exchangers. Most published nanofluid flow models assumed constant thermal conductivity and viscosity. With such great physiognomies in mind, the novelty of this work focuses on comparing the performance of the nanofluid models, Xue, and Yamada-Ota models on a stretched sheet with variable thickness under the influence of a magnetic field and quadratic thermal radiation. The altered boundary layer equations for momentum and temperature, subject to adequate boundary conditions, are numerically solved using an optimized, efficient, and extensive bvp-4c approach. The effects of non-dimensional constraints such as magnetic field, power index of velocity, wall thickness parameter, and quadratic radiation parameter on momentum and temperature profile in the boundary layer area are analyzed thoroughly and outcomes were illustrated graphically. Additionally, the consequences of certain distinctive parameters over engineering factors are also examined and results were presented in tabular form. From the outcomes, it is seen that fluid velocity slows down in the presence of a magnetic field but the opposite nature is observed in the case of temperature profile. With a higher index of velocity, the velocity profile decreases and the temperature field elevates. It has been found that the presence of quadratic convection improves the temperature field. The outcomes of the two models are compared. The Yamada-Ota model performed far better than the Xue model in the heat transfer analysis.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 6","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679647","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}
{"title":"A review on the deformation tracking methods in vision-based tactile sensing technology","authors":"Benzhu Guo \u0000 (, ), Shengyu Duan \u0000 (, ), Panding Wang \u0000 (, ), Hongshuai Lei \u0000 (, ), Zeang Zhao \u0000 (, ), Daining Fang \u0000 (, )","doi":"10.1007/s10409-024-24436-x","DOIUrl":"10.1007/s10409-024-24436-x","url":null,"abstract":"<div><p>In daily life, human need various senses to obtain information about their surroundings, and touch is one of the five major human sensing signals. Similarly, it is extremely important for robots to be endowed with tactile sensing ability. In recent years, vision-based tactile sensing technology has been the research hotspot and frontier in the field of tactile perception. Compared to conventional tactile sensing technologies, vision-based tactile sensing technologies are capable of obtaining high-quality and high-resolution tactile information at a lower cost, while not being limited by the size and shape of sensors. Several previous articles have reviewed the sensing mechanism and electrical components of vision-based sensors, greatly promoting the innovation of tactile sensing. Different from existing reviews, this article concentrates on the underlying tracking method which converts real-time images into deformation information, including contact, sliding and friction. We will show the history and development of both model-based and model-free tracking methods, among which model-based approaches rely on schematic mechanical theories, and model-free approaches mainly involve machine learning algorithms. Comparing the efficiency and accuracy of existing deformation tracking methods, future research directions of vision-based tactile sensors for smart manipulations and robots are also discussed.\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 10","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10409-024-24436-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of low-frequency vibration isolators with high-static-low-dynamic characteristic via functionally graded beam systems","authors":"Yixin Huang \u0000 (, ), Yikun Yuan \u0000 (, ), Yichen Jia \u0000 (, ), Yang Zhao \u0000 (, )","doi":"10.1007/s10409-024-23501-x","DOIUrl":"10.1007/s10409-024-23501-x","url":null,"abstract":"<div><p>This paper presents a novel and simple approach to designing low-frequency vibration isolators via functionally graded beam systems. Without complex mechanisms and nonlinear devices, high-static stiffness and wide anti-resonance frequency bands can be achieved by optimizing material gradients and auxiliary masses. The discrete equation governing the bending and vibration of the beam system is established by employing Timoshenko’s theory and a Chebyshev spectral method. The dynamic characteristics, steady-state frequency response, and bending under static loads, are numerically calculated and used to evaluate its vibration isolation performance and support stiffness. The effects of the material gradient and auxiliary masses on the force transmissibility and static stiffness were investigated. It was found that adjusting the auxiliary masses can change the position of anti-resonance peaks, and tailoring axial material gradient can broaden the anti-resonance frequency bands. Exploiting these effects and describing the axial material distribution by the Chebyshev expansions, the constrained particle swarm optimization algorithm is adopted to design two low-frequency vibration isolators, in order to demonstrate the feasibility of using functionally graded materials to isolate low-frequency vibration and maintain structural stiffness. The results show that near the operating frequency, the transmissibility decays more than 93%, more importantly, the static stiffness is larger than 190 kN/m. This work shows a promising approach to vibration isolator design, i.e., tailoring functionally graded materials to precisely manipulate structural dynamic responses.</p></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 9","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995686","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}
{"title":"Cross-scale mechanical manipulation of mobile charges in centrosymmetric semiconductors via interplay between piezoelectricity and flexoelectricity","authors":"Chao Wei \u0000 (, ), Ziwen Guo \u0000 (, ), Jian Tang \u0000 (, ), Wenbin Huang \u0000 (, )","doi":"10.1007/s10409-024-24328-x","DOIUrl":"10.1007/s10409-024-24328-x","url":null,"abstract":"<div><p>Flexoelectricity, an electromechanical coupling between strain gradient and electrical polarization in dielectrics or semiconductors, has attracted significant scientific interest. It is reported that large flexoelectric behaviors can be obtained at the nanoscale because of the size effect. However, the flexoelectric responses of centrosymmetric semiconductors (CSs) are extremely weak under a conventional beam-bending approach, owing to weak flexoelectric coefficients and small strain gradients. The flexoelectric-like effect is an enhanced electromechanical effect coupling the flexoelectricity and piezoelectricity. In this paper, a composite structure consisting of piezoelectric dielectric layers and a CS layer is proposed. The electromechanical response of the CS is significantly enhanced via antisymmetric piezoelectric polarization. Consequently, the cross-scale mechanically tuned carrier distribution in the semiconductor is realized. Meanwhile, the significant size dependence of the electromechanical fields in the semiconductor is demonstrated. The flexoelectronics suppression is found when the semiconductor thickness reaches a critical size (0.8 µm). In addition, the first-order carrier density of the composite structure under local loads is illustrated. Our results can suggest the structural design for flexoelectric semiconductor devices.\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":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889691","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}
{"title":"Nonlinear stability characteristics of piezoelectric cylindrical shells with flexoelectric effects","authors":"Wei Wang \u0000 (, ), Huilin Yin \u0000 (, ), Junlin Zhang \u0000 (, ), Jiabin Sun \u0000 (, ), Zhenhuan Zhou \u0000 (, ), Xinsheng Xu \u0000 (, )","doi":"10.1007/s10409-024-24412-x","DOIUrl":"10.1007/s10409-024-24412-x","url":null,"abstract":"<div><p>Unlike the post-buckling behaviors of classical piezoelectric cylindrical shell, the size-dependent effect of flexoelectric material and high strain gradient in the post-buckling process play an important role in the stability analysis of the micro/nano cylindrical shells. To reveal the impacts on the post-buckling of flexoelectric cylindrical shells, an accurate post-buckling model for the flexoelectric cylindrical shells under axial compression is proposed based on the higher-order shear deformation shell theory and von Karman geometrical nonlinearity. The size-dependent post-buckling equilibrium path with mode-jumping phenomena is obtained by using Galerkin’s method and Newton-Raphson method. The predicted results are in agreement with those reported in the open literature. A detailed parametric study is also carried out to investigate the influence of geometrical parameters, flexoelectric coefficients, and electric voltage on the size-dependent post-buckling behaviors of flexoelectric cylindrical shells.\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":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889810","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}
Libo Yu (, ), Weipeng Li (, ), Weizheng Lu (, ), Hui Feng (, ), Qihong Fang (, )
{"title":"Stress gradient versus strain gradient in polycrystalline high entropy alloy revealed by crystal plasticity finite element simulation","authors":"Libo Yu \u0000 (, ), Weipeng Li \u0000 (, ), Weizheng Lu \u0000 (, ), Hui Feng \u0000 (, ), Qihong Fang \u0000 (, )","doi":"10.1007/s10409-024-24267-x","DOIUrl":"10.1007/s10409-024-24267-x","url":null,"abstract":"<div><p>Gradient structures (GS) play a crucial role in achieving a balance between strength and plasticity in metals and alloys. However, there is still a lack of understanding of the mechanisms that maintain a plasticity gradient to prevent the premature failure of fine grains in GS materials. In this work, by incorporating experimental data and the Hall-Petch relationship, we develop a size-dependent crystal plasticity model to investigate the deformation mechanisms for enhancing the strength and plasticity in polycrystalline high entropy alloys. The simulations of the GS model align well with the experimental results, exhibiting strong strain and stress gradients to improve the mechanical properties. Under the conditions of significant deformation incompatibility, the strain gradient predominantly drives the enhancement of plasticity mechanisms. As the deformation incompatibility decreases, the stress gradient begins to play a significant role in comparison with the strain gradient. This shift is attributed to the regular variations in dislocation density within different domains. As the grain size gradients and loads decrease, the dislocation density becomes more uniform across the domains, hindering the formation of strong domain boundaries. While this may impede the activation of strain gradients, it facilitates the activation of stress gradients as a supplementary measure. By designing multilayered GS structures to alter the distribution of dislocation density, we can control the activation levels of stress and strain gradients, thereby influencing the plasticity mechanisms and mechanical properties of the material.\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 10","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889811","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}
{"title":"A novel paradigm for solving PDEs: multi-scale neural computing","authors":"Wei Suo \u0000 (, ), Weiwei Zhang \u0000 (, )","doi":"10.1007/s10409-024-24172-x","DOIUrl":"10.1007/s10409-024-24172-x","url":null,"abstract":"<div><p>Numerical simulation is dominant in solving partial differential equations (PDEs), but balancing fine-grained grids with low computational costs is challenging. Recently, solving PDEs with neural networks (NNs) has gained interest, yet cost-effectiveness and high accuracy remain a challenge. This work introduces a novel paradigm for solving PDEs, called multi-scale neural computing (MSNC), considering spectral bias of NNs and local approximation properties in the finite difference method (FDM). The MSNC decomposes the solution with a NN for efficient capture of global scale and the FDM for detailed description of local scale, aiming to balance costs and accuracy. Demonstrated advantages include higher accuracy (10 times for 1D PDEs, 20 times for 2D PDEs) and lower costs (4 times for 1D PDEs, 16 times for 2D PDEs) than the standard FDM. The MSNC also exhibits stable convergence and rigorous boundary condition satisfaction, showcasing the potential for hybrid of NN and numerical method.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 6","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679847","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}
Abir Dardouri, Cherif Othmani, Issam Ben Salah, Bo Zhang (, ), Anouar Njeh
{"title":"Guided waves in sandwich plates: revealing an approximate threshold of contrast material properties for Legendre polynomial method limitations","authors":"Abir Dardouri, Cherif Othmani, Issam Ben Salah, Bo Zhang \u0000 (, ), Anouar Njeh","doi":"10.1007/s10409-024-24272-x","DOIUrl":"10.1007/s10409-024-24272-x","url":null,"abstract":"<div><p>Legendre polynomial method is well-known in modeling acoustic wave characteristics. This method uses for the mechanical displacements a single polynomial expansion over the entire sandwich layers. This results in a limitation in the accuracy of the field profile restitution. Thus, it can deal with the guided waves in layered sandwich only when the material properties of adjacent layers do not change significantly. Despite the great efforts regarding this issue in the literature, there remain open questions. One of them is: “what is the exact threshold of contrasting material properties of adjacent layers for which this polynomial method cannot correctly restitute the roots of guided waves?” We investigated this numerical issue using the calculated guided phase velocities in 0°/<i>φ</i>/0°-carbon fibre reinforced plastics (CFRP) sandwich plates with gradually increasing angle <i>φ</i>. Then, we approached this numerical problem by varying the middle layer thickness <i>h</i><sub>90°</sub> for the 0°/90°/0°-CFRP sandwich structure, and we proposed an exact thickness threshold of the middle layer for the Legendre polynomial method limitations. We showed that the polynomial method fails to calculate the quasi-symmetric Lamb mode in 0°/<i>φ</i>/0°-CFRP when <i>φ</i> > 25°. Moreover, we introduced a new Lamb mode so-called minimum-group-velocity that has never been addressed in literature.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7109,"journal":{"name":"Acta Mechanica Sinica","volume":"41 6","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679750","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}
Yanhe Tao (, ), Qintao Guo (, ), Jin Zhou (, ), Jiaqian Ma (, ), Wenxing Ge (, )
{"title":"A two-step variational Bayesian Monte Carlo approach for model updating under observation uncertainty","authors":"Yanhe Tao \u0000 (, ), Qintao Guo \u0000 (, ), Jin Zhou \u0000 (, ), Jiaqian Ma \u0000 (, ), Wenxing Ge \u0000 (, )","doi":"10.1007/s10409-024-24224-x","DOIUrl":"10.1007/s10409-024-24224-x","url":null,"abstract":"<div><p>Engineering tests can yield inaccurate data due to instrument errors, human factors, and environmental interference, introducing uncertainty in numerical model updating. This study employs the probability-box (<i>p</i>-box) method for representing observational uncertainty and develops a two-step approximate Bayesian computation (ABC) framework using time-series data. Within the ABC framework, Euclidean and Bhattacharyya distances are employed as uncertainty quantification metrics to delineate approximate likelihood functions in the initial and subsequent steps, respectively. A novel variational Bayesian Monte Carlo method is introduced to efficiently apply the ABC framework amidst observational uncertainty, resulting in rapid convergence and accurate parameter estimation with minimal iterations. The efficacy of the proposed updating strategy is validated by its application to a shear frame model excited by seismic wave and an aviation pump force sensor for thermal output analysis. The results affirm the efficiency, robustness, and practical applicability of the proposed method.</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":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142679799","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}