Applied Mathematical Modelling最新文献

{"title":"Nonlinear dynamics of a misaligned and eccentric rotor system with three base motions","authors":"D.Y. Yang ,&nbsp;J.L. Huang ,&nbsp;W.D. Zhu","doi":"10.1016/j.apm.2025.116240","DOIUrl":"10.1016/j.apm.2025.116240","url":null,"abstract":"<div><div>Misalignment and eccentricity are common major faults in rotor systems, which significantly affect vibration characteristics of rotor systems. This study aims to investigate dynamic responses of a coupling-misaligned and eccentric rotor system supported by four ball bearings with cubic nonlinear contact stiffness under three base motions, i.e., base rolling, pitching, and hovering motions, contributing to a deeper understanding of vibration characteristics of rotor dynamic systems in space transportation equipment. Equations of motion of the rotor system under base motions are derived by using the Lagrangian method. The incremental harmonic balance method is used to obtain periodic solutions of the rotor system under base motions, and the Floquet theory along with the precise Hsu's method is employed to analyze stability of periodic solutions and their bifurcations. It is found that vibration intensity of the rotor system is not always aggravated under the effect of a base motion load, and it can even be suppressed in some conditions. Nevertheless, response characteristics at even multiples of the shaft rotation frequency for the misalignment fault remain significant, and these fault characteristics are consistent with those observed when the base is fixed. In addition, base motions affect the amplitude of the constant vibration response in frequency domain, leading to the deviation of disk center trajectories. Disk center trajectories shift direction varies with base motion types, potentially causing rotor-stator rubbing impacts at different locations. Furthermore, it is found that nonlinear behaviors of the rotor system change with base motions, including differences in bifurcation types and rotation speeds corresponding to bifurcations. These findings provide theoretical support for the structural design and fault diagnosis of transportation equipment that frequently undergoes spatial motions, such as aircraft engines.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116240"},"PeriodicalIF":4.4,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290534","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":"Long-term evolution model of the train-track interaction considering the concrete fatigue damage constitutive and numerical implementation","authors":"Liu Hubing ,&nbsp;Song Li ,&nbsp;Xu Lei ,&nbsp;Yu Zhiwu","doi":"10.1016/j.apm.2025.116243","DOIUrl":"10.1016/j.apm.2025.116243","url":null,"abstract":"<div><div>This paper integrates continuous damage mechanics and train-track coupled dynamic, a long-term evolution analysis model for the vehicle-track interaction considering the fatigue damage of the concrete materials is proposed, aiming to reveal the evolution mechanicians of the dynamic performance of system induced by the cyclic moving train. First, a spatial elastoplastic fatigue damage constitutive is introduced into the modelling of the vehicle-track interaction, and a numerical scheme based on the operator split method is employed to update the stress state and internal variables of track structure. Then, a consistent tangent modulus of damaged material is derived, and the quasi-static incremental method is applied to obtain the dynamic response of the track considering the material fatigue damage. In addition, a cyclic jump acceleration algorithm based on the damage variable extrapolation and prediction is constructed to achieve the high-cycle fatigue analysis of concrete, and the complete numerical implementation program is given to simulate the long-term behavior. Comprehensive comparisons of the dynamic response, i.e., stress, damage, and displacement, with published literature and ABAQUS model, demonstrate the accuracy and reliability of each part in this work. Finally, the distribution and evolution law of damage values and plastic strain of track under the train are investigated by the numerical examples, and the applicability of the long-term evolution model is elaborated. The wheel-rail dynamic effect is identified as the main internal factor that exacerbates the fatigue degradation of track structure. This work could be beneficial to accurate evaluation of the dynamic behavior evolution of track structure and train, and provides guidance for the maintenance of track structure.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116243"},"PeriodicalIF":4.4,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271538","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":"Kinematically incompatible Föppl-von Kármán plates: Analysis and numerics","authors":"Edoardo Fabbrini ,&nbsp;Andrés A. León Baldelli ,&nbsp;Pierluigi Cesana","doi":"10.1016/j.apm.2025.116234","DOIUrl":"10.1016/j.apm.2025.116234","url":null,"abstract":"<div><div>This work investigates isotropic thin plates where out-of-plane deformations arise due to membrane kinematic incompatibility of rotational type, specifically Volterra wedge disclinations, which are commonly observed in metal plates and graphene. Theoretical results are presented to guarantee the existence and regularity of equilibrium solutions in the presence of a finite number of disclinations and a dead load, under clamped boundary conditions. To solve the equilibrium equations, a numerical implementation is developed and applied to a series of parametric test studies. The finite element method adopted follows the Discontinuous Galerkin approach using continuous elements.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116234"},"PeriodicalIF":4.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241589","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":"Surrogate-based excavation trajectory generation of unmanned excavator under uncertainty","authors":"Tao Fu ,&nbsp;Zhengguo Hu ,&nbsp;Xueguan Song ,&nbsp;Guang Li ,&nbsp;Haifeng Yue","doi":"10.1016/j.apm.2025.116235","DOIUrl":"10.1016/j.apm.2025.116235","url":null,"abstract":"<div><div>Generating a reliable excavation trajectory is the essential precondition for unmanned excavators to achieve safe and energy-efficient operation. Conventional trajectory planning methods often oversimplify the geometric path by using predefined curve types for parameterization and typically neglect environmental uncertainties. These simplifications can constrain the optimization space and reduce the practical executability of the generated trajectories, ultimately limiting excavation performance and adaptability in complex, variable working conditions. To address this challenge, this study presents a surrogate-based excavation trajectory generation method that considers soil parameters uncertainty. First, the distributions of unknown parameters in soil mechanics equation are determined by minimizing discrepancies between measured and estimated excavation forces. Next, a surrogate‐based excavation trajectory generation method is proposed to enhance performance by increasing path flexibility, and reliability constraints are incorporated to mitigate the effects of soil excavability on autonomous operation. Finally, the methodology’s effectiveness is systematically validated through numerical experiments.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116235"},"PeriodicalIF":4.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144261380","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":"Semi-analytical FEM for modelling 3D guided waves scattering in an infinite plate","authors":"Chen Yang ,&nbsp;Junichi Nakaoka ,&nbsp;Sohichi Hirose","doi":"10.1016/j.apm.2025.116236","DOIUrl":"10.1016/j.apm.2025.116236","url":null,"abstract":"<div><div>Reconstructing true flaw shapes in three-dimensional (3D) structures using ultrasonic guided waves is still a challenging problem nowadays. Therefore, a thorough and visual analysis of 3D guided waves scattering interacting with defects is urgently needed. The 3D semi-analytical finite element method (FEM) proposed in this paper can not only have advantages on mesh reduction and need no absorption medium or perfectly matched layer to suppress the reflected waves compared to traditional FEM, but also can directly obtain the scattering coefficients of each guided wave to visualize the scattering phenomena and mechanism. Moreover, the virtual non-reflecting boundary is processed perfectly, thus eliminating all spurious reflected waves. A three-step strategy of this method is performed as follows: Firstly, the 3D scattered waves at the virtual boundary are represented by a series of Lamb and SH cylindrical guided waves of Bessel function form with unknown scattering coefficients; Secondly, utilizing the mode orthogonality, the unknown tractions at the virtual boundary are expressed in terms of the unknown scattering displacements at the virtual boundary via scattering coefficients; Thirdly, this linear relationship at the virtual boundary can be assembled into the global FEM matrix to solve the problem. This method is implemented to analyze the scattering phenomena due to symmetric defects in a 3D infinite plate. The correctness and effectiveness of the proposed method is finally validated compared with existing methods, and the scattering mechanisms of different defect types, shapes and sizes are discussed in detail.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116236"},"PeriodicalIF":4.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241068","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":"Task-space fixed-time bipartite tracking control for heterogeneous networked Euler-Lagrange systems","authors":"Runlong Peng ,&nbsp;Jinchen Ji ,&nbsp;Lixia Liu ,&nbsp;Zhonghua Miao ,&nbsp;Nan Li ,&nbsp;Jin Zhou","doi":"10.1016/j.apm.2025.116238","DOIUrl":"10.1016/j.apm.2025.116238","url":null,"abstract":"<div><div>This paper investigates the bipartite coordinated tracking control problem in the task-space of heterogeneous networked Euler-Lagrange systems in the fixed-time framework. A new neural network-based fixed-time hierarchical control approach is developed mainly under the directed graphs. Specifically, a distributed observer is firstly designed to estimate the desired position and velocity of the system in the fixed-time framework, and the neural network-based controller is proposed on this basis. The effect of system uncertainty is effectively mitigated and the chattering phenomenon is overcome, thus solving the bipartite coordinated tracking control problem of heterogeneous networked Euler-Lagrange systems at the control layer. In addition, the error can be kept within a small convergence region as derived by the fixed-time stability theory. Finally, the feasibility of the proposed control scheme is fully verified by numerical simulation.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116238"},"PeriodicalIF":4.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241590","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":"Numerical modelling of internal gravity waves generated by a thermal forcing in an anelastic atmospheric flow with vertical shear","authors":"Lucy J. Campbell","doi":"10.1016/j.apm.2025.116233","DOIUrl":"10.1016/j.apm.2025.116233","url":null,"abstract":"<div><div>A numerical model is presented for internal gravity waves generated by deep or shallow latent heating in the lower atmosphere. The configuration comprises a background fluid flow with vertical shear and vertical stratification in a two-dimensional computational domain. A thermal forcing term is included in the energy conservation equation for the fluid flow. This term is sinusoidal in the horizontal direction and localized in the vertical direction and it generates a perturbation in the form of an upward-propagating internal gravity wave with a horizontal wavelength corresponding to that of the thermal forcing oscillation. If there is no critical level where the background flow speed is equal to the wave phase speed, then the wave propagates to the upper boundary of the domain where a non-reflecting boundary condition or radiation condition is imposed numerically. With a vertically-sheared background flow, where a critical level is present, nonlinear wave-mean-flow interactions occur. Vertical fluxes of momentum and energy lead to the development of higher horizontal wavenumber and zero wavenumber components. There is a transfer of momentum and energy to the background flow which reduces the wave amplitude in the upper levels of the domain and results in changes in the background velocity and temperature and the development of regions of convective instability near the critical level.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116233"},"PeriodicalIF":4.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241591","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":"Water quality prediction based on different kinds of water consumption in urban areas in China","authors":"Wenwen Wu ,&nbsp;Kaihe Shi ,&nbsp;Lifeng Wu","doi":"10.1016/j.apm.2025.116237","DOIUrl":"10.1016/j.apm.2025.116237","url":null,"abstract":"<div><div>At present, water environment pollution has become one of the most serious problems which threatens human life, health, and water resources. It is important to accurately predict the water quality status for the sustainable development and management of water resources. For the characteristics of water quality research with little data, grey model is chosen as a research tool. In this paper, a grey multivariate model with fractional order new information priority combination cumulative is proposed. The grey correlation analysis was firstly used to analyze the extent to which the water quality index of 16 cities in Anhui Province was affected by four different kinds of water consumption. Then, the proposed model was used to predict the water quality index of each city. The results show that 93.75 % of the cities believe that agricultural water consumption has a significant impact on water quality index, and 81.25 % of the cities believe that industrial water consumption has a significant impact on water quality index. Only 6.25 % and 1.25 % of the cities believed that domestic water consumption and ecological water consumption had a significant impact on water quality index. In addition, the improved model can greatly improve the prediction accuracy. In the future six years, the water quality index of 10 cities shows a decreasing trend, and the water quality index of 6 cities shows an increasing trend in Anhui Province. The results of the research provide a basis for the establishment of policies related to the sustainable development management of the regional water environment and help the construction of beautiful China.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116237"},"PeriodicalIF":4.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306235","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":"High-order multi-scale neural network method for quasi-static thermo-mechanical problems of composite materials","authors":"Jiale Linghu ,&nbsp;Weifeng Gao ,&nbsp;Hao Dong ,&nbsp;Yufeng Nie ,&nbsp;Shuqi Wang","doi":"10.1016/j.apm.2025.116232","DOIUrl":"10.1016/j.apm.2025.116232","url":null,"abstract":"<div><div>The high-accuracy simulation of multi-physics and multi-scale problems of composite materials with a neural network approach remains a challenging task due to costly computation and Frequency Principle. In this study, a novel high-order multi-scale neural network approach with high-accuracy and efficiency performance is developed to compute the quasi-static thermo-mechanical problems of composite materials, which combines the computational advantages of the high-order multi-scale method and the neural network-based method. In the computational framework of high-order multi-scale neural network, the high-order multi-scale method decomposes the original complex multi-scale problem into two parts, namely, the macroscopic homogenized problem and the microscopic unit cell problems. Then the neural network method mesh-free computes these two parts. In particular, revised physics-informed neural networks are developed to calculate macroscopic homogenized thermo-mechanical problems with significant order of magnitude differences between different physical fields. Finally, the accuracy and efficiency of the proposed high-order multi-scale neural network method are demonstrated by representative numerical examples of two- and three-dimensional simulations of composite materials.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116232"},"PeriodicalIF":4.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241067","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":"Distributed large-scale joint non-uniform UAV formation path planning based on global optimal guidance","authors":"Gang Hu ,&nbsp;Peidong He ,&nbsp;Guo Wei","doi":"10.1016/j.apm.2025.116239","DOIUrl":"10.1016/j.apm.2025.116239","url":null,"abstract":"<div><div>In the military field, the utilization of unmanned aerial vehicle (UAV) formations to carry out saturation attacks on enemy forces is the development trend of future war. Traditional path planning algorithms have the disadvantages of poor real-time performance, poor flexibility, poor scalability, and weak anti-jamming ability, which make these algorithms difficult to apply in the control of large-scale joint non-uniform military UAV formations. This paper proposes a path-planning method for large-scale, low-cost military UAVs, it addresses three key aspects: system design, path-planning algorithms, and UAV safety guarantee. In system design, we implement a distributed formation control system. In this setup, individual agents can perform flight tasks independently using autonomous algorithms without needing to communicate with a central control center. In path planning algorithms, we quantify the four interactions of UAVs and combine them with the linear separation force strategy to construct a set of behavior-based formation coordination control methods through a reasonable interaction combination method. By adding guided paths, based on the integration of behavior-based formation coordination control methods, this paper retains the advantages of global path planning algorithms, such as high success rate, and local path planning algorithms, such as real-time performance. By designing a distributed formation control system with strong robustness and incorporating an escape mechanism, the system benefits from both passive and active fault-tolerant control strategies. This significantly enhances the overall stability of the system. Ablation experiments demonstrate that the components of the formation control system proposed in this paper are reasonable. Simulation experiments indicate that the distributed large-scale joint non-uniform UAV formation real-time path planning method is secure, stable, adaptable to various planning environments, and exhibits a fast convergence speed for the formation. Additionally, it is scalable, flexible, and suitable for application in large-scale clusters, among other benefits.</div></div>","PeriodicalId":50980,"journal":{"name":"Applied Mathematical Modelling","volume":"148 ","pages":"Article 116239"},"PeriodicalIF":4.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144241066","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}