Article
Mathematics
Hui Li
Summary: This paper studies the motion of a 1-D closed elastic string in a 2-D Stokes flow, introducing tangent angle and stretching functions to describe different deformations. By reformulating the problem into a parabolic system known as the contour dynamic system, the local well-posedness of the free boundary problem in Sobolev space is established under certain assumptions. It is proven that when initial configurations are sufficiently close to equilibrium, solutions can be extended globally and will converge exponentially to equilibrium state.
JOURNAL OF FUNCTIONAL ANALYSIS
(2021)
Article
Computer Science, Interdisciplinary Applications
Shang-Gui Cai, Johan Degrigny, Jean-Francois Boussuge, Pierre Sagaut
Summary: An improved coupling method of immersed boundary method and turbulence wall models on Cartesian grids is proposed to generate smooth wall surface pressure and skin friction at high Reynolds numbers. Various modifications are presented to enhance the near wall solution, and the validity of the method is demonstrated through numerical benchmark tests.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Automation & Control Systems
K. D. Do
Summary: This paper considers the problem of boundary feedback stabilization of an elastic body surrounding a viscous incompressible fluid. It gives a proof of global existence of a weak solution of the closed-loop system and handles the issue of unbounded forces induced by the fluid on the elastic body due to less regular initial values of the fluid velocity.
Article
Mathematics, Applied
Qinghe Wang, Mingyang Pan, Yu-Hau Tseng, Dongdong He
Summary: In this paper, an energy stable immersed boundary method is developed for solving deformable membrane problems with non-uniform density and viscosity. The evolution of the membrane is controlled by its tangent angle and arc length, which is different from the classic IB formulation. The proposed scheme is shown to be energy stable and capable of predicting the dynamics of extensible and inextensible interface problems with non-uniform density and viscosity.
JOURNAL OF SCIENTIFIC COMPUTING
(2023)
Article
Mathematics, Applied
Georis Billo, Michel Belliard, Pierre Sagaut
Summary: This passage discusses the importance of using numerical simulation tools in the development of new safety systems for nuclear reactors, and introduces the approach of combining different technologies to solve problems. Through validation in academic test cases, the linear interpolation technique has been found to increase accuracy while reducing computation time, and also demonstrates advantages in industrial test cases.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2021)
Article
Mathematics, Applied
Georis Billo, Michel Belliard, Pierre Sagaut
Summary: In this study, the Penalized Direct Forcing Method and linear interpolation techniques were used to simulate turbulent two-phase flows around complex geometries. The results showed that the weighted averaging method was faster in terms of execution time compared to the optimization method. Moreover, directional interpolation yielded the best results when dealing with complex geometries and relatively coarse meshes.
COMPUTERS & MATHEMATICS WITH APPLICATIONS
(2022)
Article
Mechanics
C. Chan, P. Schlatter, R. C. Chin
Summary: The flow physics of turbulent boundary layers was investigated using spectral analysis based on the spanwise scale decomposition of the Reynolds stress transport equation with data obtained from direct numerical simulation. The study revealed evidence of inverse turbulent kinetic energy transfer occurring in the near-wall region, as well as inverse transfer of Reynolds shear stress transport across the entire boundary layer. Interactions between large-scale structures and the free stream flow were also observed at the edge of the boundary layer.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Magnus Svard
Summary: This study focuses on deriving boundary conditions for the initial-boundary value Euler equations to establish an entropy bound for the physical (Navier-Stokes) entropy. The research begins by reviewing the entropy bound obtained for standard no-penetration wall boundary conditions and proposes a numerical implementation. The main results include deriving full-state boundary conditions and demonstrating that linear theory boundary conditions are unable to bound the entropy, requiring nonlinear bounds and additional boundary conditions. The theoretical findings are supported by numerical experiments.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Mathematics, Applied
John Sebastian H. Simon, Hirofumi Notsu
Summary: This study investigates the convective boundary condition (CBC) on an outflow boundary for flow problems governed by the Navier-Stokes equations, and establishes the existence and uniqueness results of solutions. Numerical observations of different flow conditions are made by comparing with other known outflow boundary conditions. The CBC has the properties of being natural from a mathematical viewpoint, allow for discussions on the existence and uniqueness of solutions, and can be easily implemented with numerical methods such as the Newton method and the adjoint method.
APPLIED MATHEMATICS LETTERS
(2022)
Article
Mathematics, Applied
Tsegaye G. Ayele, Mulugeta A. Dagnaw
Summary: This paper considers the boundary-domain integral equations for a compressible Stokes system in 2D with variable coefficients. An appropriate parametrix is used to simplify the problem, and conditions are set to ensure unique solvability. Properties of potential operators and equivalence to the mixed boundary value problem are investigated and proved in appropriate Sobolev spaces.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Mathematics, Applied
Tsegaye G. Ayele, Mulugeta A. Dagnaw
Summary: This paper considers the Dirichlet and Neumann boundary value problems for the steady-state Stokes system of partial differential equations for a compressible viscous fluid with variable viscosity coefficient in a two-dimensional bounded domain. It shows the equivalence of the BDIE systems to the Dirichlet and Neumann BVPs and the invertibility of the corresponding boundary-domain integral operators in appropriate Sobolev spaces. The special properties of BDIEs in the two-dimensional case, compared to the three dimension, are due to the logarithmic term in the parametrix for the associated partial differential equations.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Mathematics, Applied
Yong Wang, Wenpei Wu
Summary: This study focuses on the initial-boundary value problems of the three-dimensional compressible elastic Navier-Stokes-Poisson equations under different boundary conditions for the electrostatic potential. The unique global solution near a constant equilibrium state in H-2 space is obtained, and it is proven that the solution decays to the equilibrium state at an exponential rate as time tends to infinity. This is the first result for the three-dimensional elastic Navier-Stokes-Poisson equations under various boundary conditions for the electrostatic potential.
ADVANCES IN NONLINEAR ANALYSIS
(2021)
Article
Computer Science, Interdisciplinary Applications
Antoine Michael Diego Jost, Stephane Glockner
Summary: The article proposes linear/quadratic square shifting methods to improve the accuracy and convergence of ghost-cell immersed boundary methods for Cartesian grids. The methods aim to increase the order of convergence while maintaining a maximum stencil size of 2, and are evaluated through a comprehensive verification and validation process.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Xinjie Ji, James Gabbard, Wim M. van Rees
Summary: This paper introduces a sharp-interface approach based on the immersed interface method for handling the one- and two-way coupling between an incompressible flow and rigid bodies using the vorticity-velocity Navier-Stokes equations. The authors develop a moving boundary treatment and a two-way coupling methodology that do not require the pressure field. Extensive testing shows that the resulting solver achieves second-order accuracy and provides efficiency benefits compared to a representative first-order approach.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Engineering, Multidisciplinary
Haifeng Ji, Feng Wang, Jinru Chen, Zhilin Li
Summary: This paper presents an immersed finite element (IFE) method for solving Stokes interface problems with a piecewise constant viscosity coefficient that has a jump across the interface. The method modifies the traditional finite element near the interface according to the interface jump conditions and proves the unisolvent property and optimal approximation capabilities of the IFE method. The stability and optimal error estimates are also derived rigorously.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Thermodynamics
Mithun Kanchan, Ranjith Maniyeri
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2019)
Article
Thermodynamics
Mithun Kanchan, Ranjith Maniyeri
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2020)
Article
Engineering, Mechanical
Mithun Kanchan, Ranjith Maniyeri
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2020)
Article
Engineering, Mechanical
Sri Charan Akula, Ranjith Maniyeri
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2019)
Article
Mechanics
Mithun Kanchan, Ranjith Maniyeri
FLUID DYNAMICS RESEARCH
(2020)
Article
Environmental Sciences
B. C. Anilkumar, Ranjith Maniyeri, S. Anish
Summary: This study aims to determine the optimal surface area of a solar cooker using heat loss and design equations, and evaluates the performance of the cooker with sensible heat storage materials. The results show that the cooker surface area is 0.36 m², with an iron grits:sand:brick powder:charcoal powder ratio of 1:2:2:3. The performance indicators including first and second figures of merit and thermal and exergy efficiency are calculated to be 0.085, 0.319, 16.1%, and 0.61% respectively, with the water temperature in the cooker maintained above 70°C until 6 PM.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Energy & Fuels
B. C. Anilkumar, Ranjith Maniyeri, S. Anish
Summary: This study aims to select the optimal phase change material (PCM) for solar box cookers by using multi-criteria decision-making methods and optimization algorithms, ultimately determining erythritol as the best choice. The computational procedure and iterative solver were used to calculate that erythritol requires less quantity compared to other PCMs, demonstrating good agreement with experimental studies.
JOURNAL OF ENERGY STORAGE
(2021)
Proceedings Paper
Computer Science, Theory & Methods
Vedant Dhruv, Ujwal Mishra, Ranjith Maniyeri
MATHEMATICAL MODELLING AND SCIENTIFIC COMPUTING WITH APPLICATIONS, ICMMSC 2018
(2020)
Proceedings Paper
Engineering, Mechanical
Mithun Kanchan, Ranjith Maniyeri
RECENT ASIAN RESEARCH ON THERMAL AND FLUID SCIENCES, AJWTF7 2018
(2020)
Proceedings Paper
Engineering, Mechanical
Deepak Kumar Kolke, M. Arun, Ranjith Maniyeri
RECENT ASIAN RESEARCH ON THERMAL AND FLUID SCIENCES, AJWTF7 2018
(2020)
Proceedings Paper
Engineering, Mechanical
Ranjith Maniyeri, Sangmo Kang
RECENT ASIAN RESEARCH ON THERMAL AND FLUID SCIENCES, AJWTF7 2018
(2020)
Article
Thermodynamics
Himanshu Madhukar Patil, Ranjith Maniyeri
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2019)
Article
Thermodynamics
Jagadeesh Indukuri, Ranjith Maniyeri
INTERNATIONAL JOURNAL OF HEAT AND TECHNOLOGY
(2018)
Article
Engineering, Multidisciplinary
Jagadeesh Varma Indukuri, Ranjith Maniyeri
ALEXANDRIA ENGINEERING JOURNAL
(2018)
Proceedings Paper
Physics, Applied
Mithun Kanchan, Ranjith Maniyeri
ADVANCES IN MECHANICAL DESIGN, MATERIALS AND MANUFACTURE
(2018)
Article
Engineering, Multidisciplinary
A. A. Aganin, A. I. Davletshin
Summary: A mathematical model of interaction of weakly non-spherical gas bubbles in liquid is proposed in this paper. The model equations are more accurate and compact compared to existing analogs. Five problems are considered for validation, and the results show good agreement with experimental data and numerical solutions. The model is also used to analyze the behavior of bubbles in different clusters, providing meaningful insights.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Hao Wu, Jie Sun, Wen Peng, Lei Jin, Dianhua Zhang
Summary: This study establishes an analytical model for the coupling of temperature, deformation, and residual stress to explore the mechanism of residual stress formation in hot-rolled strip and how to control it. The accuracy of the model is verified by comparing it with a finite element model, and a method to calculate the critical exit crown ratio to maintain strip flatness is proposed.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Shengwen Tu, Naoki Morita, Tsutomu Fukui, Kazuki Shibanuma
Summary: This study aimed to extend the finite element method to cope with elastic-plastic problems by introducing the s-version FEM. The s-version FEM, which overlays a set of local mesh with fine element size on the conventional FE mesh, simplifies domain discretisation and provides accurate numerical predictions. Previous applications of the s-version FEM were limited to elastic problems, lacking instructions for stress update in plasticity. This study presents detailed instructions and formulations for addressing plasticity problems with the s-version FEM and analyzes a stress concentration problem with linear/nonlinear material properties.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Bo Fan, Zhongmin Wang
Summary: A 3D rotating hyperelastic composite REF model was proposed to analyze the influence of tread structure and rotating angular speed on the vibration characteristics of radial tire. Nonlinear dynamic differential equations and modal equations were established to study the effects of internal pressure, tread pressure sharing ratio, belt structure, and rotating angular speed on the vibration characteristics.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
X. W. Chen, Z. Q. Yue, Wendal Victor Yue
Summary: This paper examines the axisymmetric problem of a flat mixed-mode annular crack near and parallel to an arbitrarily graded interface in functionally graded materials (FGMs). The crack is modeled as plane circular dislocation loop and an efficient solution for dislocation in FGMs is used to calculate the stress field at the crack plane. The analytical solutions of the stress intensity factors are obtained and numerical study is conducted to investigate the fracture mechanics of annular crack in FGMs.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Xumin Guo, Jianfei Gu, Hui Li, Kaihua Sun, Xin Wang, Bingjie Zhang, Rangwei Zhang, Dongwu Gao, Junzhe Lin, Bo Wang, Zhong Luo, Wei Sun, Hui Ma
Summary: In this study, a novel approach combining the transfer matrix method and lumped parameter method is proposed to analyze the vibration response of aero-engine pipelines under base harmonic and random excitations. The characteristics of the pipelines are investigated through simulation and experiments, validating the effectiveness of the proposed method.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Xiangyu Sha, Aizhong Lu, Ning Zhang
Summary: This paper investigates the stress and displacement of a layered soil with a fractional-order viscoelastic model under time-varying loads. The correctness of the solutions is validated using numerical methods and comparison with existing literature. The research findings are of significant importance for exploring soil behavior and its engineering applications under time-varying loads.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Thuy Dong Dang, Thi Kieu My Do, Minh Duc Vu, Ngoc Ly Le, Tho Hung Vu, Hoai Nam Vu
Summary: This paper investigates the nonlinear torsional buckling of corrugated core sandwich toroidal shell segments with functionally graded graphene-reinforced composite (FG-GRC) laminated coatings in temperature change using the Ritz energy method. The results show the significant beneficial effects of FG-GRC laminated coatings and corrugated core on the nonlinear buckling responses of structures.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Zhihao Zhai, Chengbiao Cai, Qinglai Zhang, Shengyang Zhu
Summary: This paper investigates the effect of localized cracks induced by environmental factors on the dynamic performance and service life of ballastless track in high-speed railways. A mathematical approach for forced vibrations of Mindlin plates with a side crack is derived and implemented into a train-track coupled dynamic system. The accuracy of this approach is verified by comparing with simulation and experimental results, and the dynamic behavior of the side crack under different conditions is analyzed.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
James Vidler, Andrei Kotousov, Ching-Tai Ng
Summary: The far-field methodology, developed by J.C. Maxwell, is utilized to estimate the effective third order elastic constants of composite media containing random distribution of spherical particles. The results agree with previous studies and can be applied to homogenization problems in other fields.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Kim Q. Tran, Tien-Dat Hoang, Jaehong Lee, H. Nguyen-Xuan
Summary: This study presents novel frameworks for graphene platelets reinforced functionally graded triply periodic minimal surface (GPLR-FG-TPMS) plates and investigates their performance through static and free vibration analyses. The results show that the mass density framework has potential for comparing different porous cores and provides a low weight and high stiffness-to-weight ratio. Primitive plates exhibit superior performance among thick plates.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Bence Hauck, Andras Szekrenyes
Summary: This study explores several methods for computing the J-integral in laminated composite plate structures with delamination. It introduces two special types of plate finite elements and a numerical algorithm. The study presents compact formulations for calculating the J-integral and applies matrix multiplication to take advantage of plate transition elements. The models and algorithms are applied to case studies and compared with analytical and previously used finite element solutions.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Wu Ce Xing, Jiaxing Wang, Yan Qing Wang
Summary: This paper proposes an effective mathematical model for bolted flange joints to study their vibration characteristics. By modeling the flange and bolted joints, governing equations are derived. Experimental studies confirm that the model can accurately predict the vibration characteristics of multiple-plate structures.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Pingchao Yu, Li Hou, Ke Jiang, Zihan Jiang, Xuanjun Tao
Summary: This paper investigates the imbalance problem in rotating machinery and finds that mass imbalance can induce lateral-torsional coupling vibration. By developing a model and conducting detailed analysis, it is discovered that mass imbalance leads to nonlinear time-varying characteristics and there is no steady-state torsional vibration in small unbalanced rotors. Under largely unbalanced conditions, both resonant and unstable behavior can be observed, and increasing lateral damping can suppress instability and reduce lateral amplitude in the resonance region.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Yong Cao, Ziwen Guo, Yilin Qu
Summary: This paper investigates the mechanically induced electric potential and charge redistribution in a piezoelectric semiconductor cylindrical shell. The results show that doping levels can affect the electric potentials and mechanical displacements, and alter the peak position of the zeroth-order electric potential. The doping level also has an inhibiting effect on the first natural frequency. These findings are crucial for optimizing the design and performance of cylindrical shell-shaped sensors and energy harvesters.
APPLIED MATHEMATICAL MODELLING
(2024)