Article
Multidisciplinary Sciences
Valentin Lychagin
Summary: This work investigates the algebraic and differential SO(3)-invariants of spherical harmonics, and explores the fields of rational algebraic and rational differential invariants in describing the regular SO(3)-orbits of spherical harmonics.
Article
Mechanics
M. S. Faltas, H. H. Sherief, Allam A. Allam, Baraa A. Ahmed
Summary: This study investigates the axisymmetric motion of a spherical particle at a porous interface under small Reynolds and capillary numbers, utilizing the Brinkman equation and slip boundary condition. A semi-analytical approach based on a collocation technique is used to obtain collocation solutions for the normalized hydrodynamic drag force and torque, showing good convergence under various conditions. The results for the normalized drag and torque coefficients are in good agreement with existing literature for limiting cases.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2021)
Article
Mathematics, Applied
Durmus Albayrak
Summary: In this paper, various theorems and relationships are examined using a generalized Laplace-type integral transform. The harmonic oscillator, initial-boundary problems, and integral equations in non-resisting and resisting mediums are solved through this integral transform. Additionally, the well-known Basel problem series is obtained using a similar approach. Moreover, a numerical comparison between the classical and newly introduced integral transforms is conducted.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Article
Mathematics
Xingxing Yue, Buwen Jiang, Xiaoxuan Xue, Chao Yang
Summary: A localized virtual boundary element-meshless collocation method (LVBE-MCM) is proposed to solve Laplace and Helmholtz equations in complex 2D geometries. The LVBE-MCM simplifies the traditional virtual boundary element method by locally approximating the physical quantities and avoiding the evaluation of singular integrals. Numerical experiments show that the LVBE-MCM is accurate, stable, and convergent for solving both Laplace and Helmholtz equations.
Article
Nuclear Science & Technology
M. T. Capilla, C. F. Talavera, D. Ginestar, G. Verdu
Summary: This study developed and validated node homogenization methods based on one and three-dimensional node equivalent problems to improve the treatment of rod cusping effect in volume weighted method. The numerical implementation of these techniques in a numerical approach based on general spherical harmonics showed the validity and convergence of P-1 and P-3 approximations in AECL-7236 PHWR benchmark transient, indicating the method's ability to provide accurate results for relative power and scalar flux with coarse spatial mesh combined with advanced homogenization techniques.
PROGRESS IN NUCLEAR ENERGY
(2021)
Article
Thermodynamics
Hany H. Sherief, Farid A. Hamza, Abd Ellatief M. Abd Ellatief
Summary: In this study, the 3D problems of generalized theory of thermoelasticity in spherical regions were investigated and the closed form solutions for temperature, displacement components, and stress tensor components were obtained using Laplace transform. This work is the first attempt to solve the full system of equations of generalized thermoelasticity in spherical regions without neglecting any governing equations.
JOURNAL OF THERMAL STRESSES
(2022)
Article
Engineering, Multidisciplinary
Jiaxing Cheng, Bangjian Liu, Xiaolin Cao, Zhaoxia Li
Summary: For the first time, the boundary element method known as Trefftz Method is used to solve fracture mechanics problems of quasicrystals. The collocation Trefftz method is demonstrated as an excellent numerical method for anti-plane fracture problems in quasicrystals plate, with focus on the effects of geometry size, loadings, and materials properties on fracture results. The study concludes that the Trefftz method is effective for materials with three dimensional constitutive relations like piezoelectric quasicrystals.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2021)
Article
Mathematics, Applied
Rim Gouia-Zarrad, Souvik Roy, Sunghwan Moon
Summary: This paper investigates a spherical Radon transform that maps a function to its surface integrals over spheres with a fixed angular span. Unique results are presented for the transform in the case of a fixed angular span, with simulation results for numerical inversion in the special case of the spherical cap Radon transform.
APPLIED MATHEMATICS AND COMPUTATION
(2021)
Article
Mathematics
Sandeep Kumar, Rajesh K. Pandey, H. M. Srivastava, G. N. Singh
Summary: This paper presents a convergent collocation method for finding the numerical solution of a generalized fractional integro-differential equation (GFIDE) using Jacobi poly-fractonomials. The GFIDE is defined in terms of the recently introduced B-operator and converges to Caputo fractional derivative and other fractional derivatives in special cases. The method's convergence and error analysis are established, and simulation results validate the theoretical findings for both linear and nonlinear cases of the considered GFIDEs.
Article
Nuclear Science & Technology
Abhishek Mishra, Aditi Ray, Tej Singh
Summary: This study derives the Simplified P-N (SPN) equations using a modified version of ansatz proposed by Pomraning and a variational method. New boundary and interface conditions for the SPN equations are derived based on the corresponding angular flux expression. The equivalence between the derived equations and a specific case of Generalized SPN (GSP(N)) proposed by Chao is demonstrated.
ANNALS OF NUCLEAR ENERGY
(2022)
Article
Engineering, Multidisciplinary
D. A. Hammad
Summary: The RLW and MRLW equations are numerically solved using Bernstein polynomials in both space and time directions based on Kronecker product. A new Bernstein collocation method is applied and convergence study is conducted. Conservation properties and accuracy testing are also investigated in this study.
AIN SHAMS ENGINEERING JOURNAL
(2021)
Article
Mathematics, Applied
Gabriel Beiner, William Verreault
Summary: We prove that the 2-sphere does not have symmetry of Lp norms of eigenfunctions of the Laplacian for p > 6, which addresses a question posed by Jakobson and Nadirashvili. In other words, there exists a sequence of spherical eigenfunctions *n, with eigenvalues An approaching infinity as n approaches infinity, such that the ratio of the Lp norms of the positive and negative parts of the eigenfunctions does not converge to 1 when p > 6. Our proof relies on fundamental properties of the Legendre polynomials and Bessel functions of the first kind.
JOURNAL OF SPECTRAL THEORY
(2023)
Article
Physics, Multidisciplinary
Bewar A. Mahmood, Shko A. Tahir, Karwan H. F. Jwamer
Summary: In this work, a numerical solution is investigated for generalized Kuramoto-Sivashinksy (GKS) problems using the collocation of the quantic B-spline (QBS) and high-order strong stability-preserving Runge-Kutta (SSPRK54) scheme. The proposed technique ensures efficiency and accuracy in capturing the natural behavior of the problems and requires less storage space.
Article
Engineering, Multidisciplinary
Yan Shang, Yu-Hao Mao, Song Cen, Chen-Feng Li
Summary: A new displacement-based Trefftz plate element is developed for size-dependent bending analysis of thin plate structures, incorporating the modified couple stress theory and generalized conforming theory, with satisfactory numerical performance.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2021)
Article
Telecommunications
Menguc Oner, Esra Sorguven
Summary: Diffusive molecular communications (DMC) rely on the Brownian motion of dedicated molecules to transmit information. This study investigates the directional signal propagation characteristics for a point source on a spherical surface and explores the effects of physical and chemical parameters on signal propagation in DMC channels.
IEEE COMMUNICATIONS LETTERS
(2022)
Article
Mechanics
Yang Chen, Zhenqiang Zhao, Dongfeng Li, Zaoyang Guo, Leiting Dong
Summary: This paper presents a micromechanics-based constitutive model for linear viscoelastic fiber-reinforced composites, which simplifies the study of mechanical responses by decomposing deformations and utilizing effective time-dependent relaxation functions and referred elastic stresses. The model facilitates studying the effective mechanical behaviors of composites in both time and frequency domains.
COMPOSITE STRUCTURES
(2021)
Article
Mechanics
Cezhou Chao, Hanlin Guo, Peng Yan, Leiting Dong
Summary: Biological staggered composites, such as bone, nacre, and dentin, possess superior energy dissipation capacity compared to conventional materials. Various staggered microstructures are observed, including symmetric and asymmetric staggered structures with nanoscale platelet thickness. A tension-shear chain model with tension region (TR) is proposed to investigate the synergy of platelet layouts, interface effects, and tension region. Optimal dynamic properties of staggered nanocomposites can be achieved by designing structures with suitable platelet layouts and distribution.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Aerospace
Xuan Zhou, Shuangxin He, Leiting Dong, Satya N. Atluri
Summary: In this paper, a reduced-order simulation approach is developed to achieve real-time prediction of crack growth in complex structures. By combining symmetric Galerkin boundary element method-finite element method (SGBEM-FEM) coupling method with machine learning methods, the proposed approach can automatically simulate hundreds of crack samples and establish the relation between crack sizes/shapes and crack-front stress intensity factors. This method provides a key simulation technology for realizing the digital twin of complex structures.
Article
Engineering, Multidisciplinary
Kailei Wang, Baoying Shen, Mingjing Li, Leiting Dong, Satya N. Atluri
Summary: The study developed a numerical method combining the Fragile Points Method (FPM) and an interface debonding model to predict the strength and crack growth of U-notched specimens made of brittle materials. The method allows for simulating crack initiation and propagation without prior knowledge of fracture patterns, providing a useful tool for engineering structural design practices.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Shuangxin He, Leiting Dong, Satya N. Atluri
Summary: This paper presents a weakly-singular SGBEM method for solving the fracture mechanics analysis problems of three-dimensional solid structures in thermal environments, transforming domain integrals induced by temperature fields into boundary integrals, retaining the advantages of SGBEM, and providing several examples for validation.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Mechanics
Yezeng Huang, Wei Shi, Hanlin Guo, Cezhou Chao, Mingjie Liu, Leiting Dong
Summary: This study investigates the interface effects on the viscoelastic properties of PDMS/SiO2 nanocomposites using a multiscale model. The molecular dynamics (MD) model of the interface at the nanoscale and the unit cell model of the nanocomposites at the mesoscale were combined to establish the model. The results show that the interface region has different viscoelastic properties compared to the pure PDMS matrix and bulk SiO2. The unit cell model demonstrates that the dynamic shear moduli of the nanocomposites can be significantly improved by the interface effects. This study reveals the mechanism of how interface effects enhance the viscoelastic properties of PDMS/SiO2 nanocomposites and can contribute to the design of nanocomposites with high stiffness and damping properties.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2022)
Article
Chemistry, Physical
Ke Chen, Xuke Tang, Binbin Jia, Cezhou Chao, Yan Wei, Junyu Hou, Leiting Dong, Xuliang Deng, Ting-Hui Xiao, Keisuke Goda, Lin Guo
Summary: Inspired by the heterophase structure of nacre, a centimetre-sized bulk material consisting of graphene oxide (GO) and amorphous/crystalline MnO2 nanosheets adhered together with polymer-based crosslinkers was prepared, exhibiting high flexural strength and fracture toughness. Experimental and numerical analyses revealed that the ordered heterophase structure and synergistic crosslinking interactions across multiscale interfaces contribute to the superior mechanical properties of the material.
Article
Computer Science, Interdisciplinary Applications
Konstantinos A. Mountris, Leiting Dong, Yue Guan, Satya N. Atluri, Esther Pueyo
Summary: Meshless methods are becoming popular for simulating cardiac electrophysiology without the need for a mesh. The Fragile Points Method (FPM) is introduced as a new meshless method that allows for accurate integration and improved efficiency, while enabling the imposition of essential boundary conditions.
JOURNAL OF COMPUTATIONAL SCIENCE
(2022)
Article
Engineering, Aerospace
Xuan Zhou, Daniele Oboe, Dario Poloni, Claudio Sbarufatti, Leiting Dong, Marco Giglio
Summary: In the field of adhesive bonding in aeronautic structures, debonding under fatigue loading is a common failure mode. Researchers have developed a joint distribution adaptation method for regression to address multi-output problems, demonstrating significant improvements in damage quantification accuracy. The proposed approach could potentially be integrated into fleet-level digital twins for heterogeneous systems with nominally identical components.
Article
Engineering, Aerospace
Fubin Zhao, Xuan Zhou, Chaoyang Wang, Leiting Dong, Satya N. Atluri
Summary: Setting inspection intervals based on accurate fatigue crack size prediction is crucial for maintaining the integrity of aeronautical structures. However, the current fixed interval inspection strategy faces challenges in managing aircraft with diverse damage states due to uncertainties in fatigue crack growth and prognosis. This study proposes an intelligent crack inspection strategy using a digital twin and a dynamic Bayesian network to adaptively set inspection intervals based on a reduced-order fracture mechanics simulation methodology, a validated fatigue crack growth model, and historical inspection results.
Article
Engineering, Aerospace
Xuan Zhou, Claudio Sbarufatti, Marco Giglio, Leiting Dong, Satya N. Atluri
Article
Engineering, Mechanical
Xuan Zhou, Claudio Sbarufatti, Marco Giglio, Leiting Dong
Summary: Online damage quantification suffers from insufficient labeled data, but adopting domain adaptation can improve its accuracy. However, existing domain adaptation methods are not suitable for damage quantification as it is a regression problem with continuous labels. This study proposes a novel domain adaptation method, the Online Fuzzy-set-based Joint Distribution Adaptation for Regression, which converts real-valued labels into fuzzy class labels and measures distribution discrepancy to achieve accurate damage quantification. The proposed method is demonstrated to significantly improve damage quantification in a realistic environment, and it is expected to be applied to fleet-level digital twin considering individual differences.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Engineering, Aerospace
Fubin Zhao, Xuan Zhou, Shuangxin He, Chaoyang Wang, Leiting Dong, Satya N. Atluri
Summary: This study introduces a reduced-order modeling (ROM) method for predicting nonplanar crack growth in structural digital twins. The method represents the entire crack surface morphology using a B-spline surface, which captures its impact on crack growth. The proposed method demonstrates superior fracture mechanics parameter prediction and is three orders of magnitude more efficient than full-order simulation.
Article
Engineering, Multidisciplinary
Shuangxin He, Chaoyang Wang, Xuan Zhou, Leiting Dong, Satya N. Atluri
Summary: The Symmetric Galerkin Boundary Element Method is advantageous for linear elastic fracture and crack growth analysis of solid structures. However, when engineering structures are subjected to body forces such as rotational inertia and gravitational loads, additional domain integral terms will require meshing of the interior of the domain. This study develops a weakly-singular SGBEM for fracture analysis of three-dimensional structures considering rotational inertia and gravitational forces, transforming the domain integral terms into boundary integrals.
CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES
(2022)
Article
Engineering, Multidisciplinary
Kailei Wang, Mingjing Li, Peng Yan, Leiting Dong
Summary: The main goal of this study is to investigate the ballistic performance of multi-layered moderately-thick metallic targets. Experimental and numerical methods were used to analyze the influence of target configurations (interlayer connection and number of layers) on the ballistic performance. The results show that contacted and adhesive targets exhibit better performance than monolithic targets, and four-layered targets outperform eight-layered targets with the same connection type. Numerical simulations indicate that petal formation and friction play significant roles in the ballistic performance of the targets.
CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES
(2022)
Article
Engineering, Multidisciplinary
Dongliang Ji, Hui Cheng, Hongbao Zhao
Summary: The influence of crystal size on the macroscopic parameters of sandstone samples is studied using a rock model based on the Voronoi tessellated model. It is found that decreasing crystal size results in increased strength and elastic modulus. Strain energy density (SED) is shown to help explain the failure mechanisms of the sandstone samples. A constitutive model that considers the heterogeneity in elastic modulus and rock strength is developed and is in good agreement with experimental results. The study also identifies the triggering of surface damage on slopes by vibration excitation in engineering applications as well as proposes a constitutive model for quantitatively evaluating damage accumulation in mining tunnels.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Francesco Tornabene, Matteo Viscoti, Rossana Dimitri
Summary: This manuscript investigates the dynamic properties of doubly-curved shell structures laminated with innovative materials using the Generalized Differential Quadrature (GDQ) method. The displacement field variable follows the Equivalent Single Layer (ESL) approach, and the geometrical description of the structures is distorted by generalized isogeometric blending functions. Through non-uniform discrete computational grid, the fundamental equations derived from the Hamiltonian principle are solved in strong form. Parametric investigations show the influence of material property variation on the modal response of the structures.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Duy-Khuong Ly, Ho-Nam Vu, Chanachai Thongchom, Nguyen-Thoi Trung
Summary: This paper presents a novel numerical approach for nonlinear analysis and smart damping control in laminated functionally graded carbon nanotube reinforced magneto-electro-elastic (FG-CNTMEE) plate structures, taking into account multiple physical fields. The approach employs a multi-physical coupling isogeometric formulation to accurately capture the nonlinear strain-displacement relationship and the magneto-electro-elastic coupling properties. The smart constrained layer damping treatment is applied to achieve nonlinear damped responses. The formulation is transformed into the Laplace domain and converted back to the time domain through inverse techniques for smart control using viscoelastic materials.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Xiaoyang Xu, Jie Cheng, Sai Peng, Peng Yu
Summary: In this study, a smoothed particle hydrodynamics (SPH) method is developed to simulate viscoelastic fluid flows governed by the Phan-Thien-Tanner (PTT) constitutive equation. The method is validated by comparing its solutions with those obtained by the finite volume method (FVM). The method is also used to simulate the impact behavior and dynamics of a viscoelastic droplet, and the influences of various parameters are investigated. The results demonstrate the accuracy and capability of the SPH method in describing the rheological properties and surface variation characteristics of viscoelastic fluid flows.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Xueying Zhang, Yangjiong Wu
Summary: This paper proposes a high resolution strategy for the localized method of approximate particular solutions (LMAPS). The strategy aims to improve the accuracy and stability of numerical calculation by selecting upwind interpolation templates. Numerical results demonstrate that the proposed high-resolution LMAPS is effective and accurate, especially for solving the Navier-Stokes equations with high Reynolds number.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Yong-Tong Zheng, Yijun Liu, Xiao-Wei Gao, Yang Yang, Hai-Feng Peng
Summary: Structures with holes are common in engineering applications. Analyzing stress concentration effects caused by holes using FEM or BEM is challenging and time-consuming. This paper proposes improved methods for simulating holes and cylinders, reducing the number of nodes while maintaining stress accuracy. Numerical examples demonstrate the accuracy and efficiency of the proposed methods.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Chein-Shan Liu, Chung-Lun Kuo
Summary: The paper presents two new families of fundamental solutions for the 3D Laplace equation and proposes the methods of pseudo fundamental solutions and anisotropic fundamental solutions, which outperform the traditional 3D MFS.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Sima Shabani, Miroslaw Majkut, Slawomir Dykas, Krystian Smolka, Esmail Lakzian
Summary: This study validates and simulates steam condensing flows using different condensation models and equations of state, identifying the most suitable model. The results highlight the importance of choosing the appropriate numerical model for accurately predicting steam condensation flows.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
D. L. Guo, H. H. Zhang, X. L. Ji, S. Y. Han
Summary: In this study, the mechanical behaviors of 2-D orthotropic composites with arbitrary holes were investigated using the numerical manifold method (NMM). The proposed method was verified and found to have good convergence and accuracy. Additionally, the effects of material principal direction and hole configurations on the mechanical behaviors of the orthotropic composites were revealed.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Giacomo Rosilho de Souza, Rolf Krause, Simone Pezzuto
Summary: In this paper, we propose a boundary element method for accurately solving the cell-by-cell bidomain model of electrophysiology. The method removes the degeneracy in the system and reduces the number of degrees of freedom. Numerical experiments demonstrate the exponential convergence of our scheme in space and several biologically relevant experiments are provided.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Riku Toshimitsu, Hiroshi Isakari
Summary: This study extends a recent paper by Lai et al. (2018) by introducing a novel boundary integral formulation for scalar wave scattering analysis in two-dimensional layered and half-spaces. The modified integral formulation eliminates fictitious eigenvalues and reasonable parameter settings ensure efficient and accurate numerical solutions. The proposed method is demonstrated to be effective through numerical examples.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Ebutalib Celik, Merve Gurbuz-Caldag
Summary: In this paper, a new meshless method based on domain decomposition for an L-shaped domain is proposed, which uses RBF-FD formulation at interface points and classical FD in sub-regions to improve the solution accuracy. The proposed numerical method is applied to simulate benchmark results for a divided-lid driven cavity and solve Navier-Stokes equations with Lorentz force term in a single-lid L-shaped cavity exposed to inclined magnetic field, and the flow structure is analyzed in terms of streamline topology under different magnetic field rotations and strengths.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Engineering, Multidisciplinary
Hanqing Liu, Fajie Wang, Lin Qiu, Cheng Chi
Summary: This paper presents a novel method that combines the singular boundary method with the Loop subdivision surfaces for acoustic simulation of complex structures, overcoming technical challenges in handling boundary nodes.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
