检索结果-南通市图书馆

Simulation of submerged granular flows by development of a twophase incompressible explicit mesh-free method

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2023年第4期38卷 530-542页

作者： Tibing Xu Shuangke Sun Peng Wu State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research School of Civil & Environmental Engineering and Geography Science Ningbo University Faculty of Engineering and Applied Science University of Regina

The interaction between fluid and sediment particles is widely involved in hydraulic engineering problems. In the current study, an explicit incompressible mesh-free method in the framework of the Moving Particle Semi-implicit(MPS) method is proposed to simulate the interaction between the two phases in submerged conditions. The proposed method solves two sets of the continuity and momentum equations, respectively, for the fluid phase and the sediment phase according to the mixture theory. In the method, the pressure and velocity fields are explicitly calculated for the sediment phase with the solid concentration obtained from the mixture theory, in which a rheology model is used to account for the viscosity and shear stress. The governing equations for the fluid are solved using the predictor-corrector time-splitting scheme and the resulting Poisson equation for pressure is calculated using an explicit scheme. In each loop, the discretized points move according to the velocity of the fluid in the mesh-free Lagrangian approach. The proposed method is used to simulate the submerged granular flows including submerged granular column collapse, submerged granular sliding on slopes, and erodible dambreak flow. In the simulations, the parameters of particle distance and collision distance in the numerical method are investigated. It is found that the flow characteristics in the granular flows are reflected by the proposed method and the simulated free surface and water-sediment interface profiles are in good agreement with experimental observations.

关键词： mesh-free method Explicit method Mixture theory Sediment transport Water-sediment interface

Wavelet Multi-Resolution Interpolation Galerkin method for Linear Singularly Perturbed Boundary Value Problems

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第4期139卷 297-318页

作者： Jiaqun Wang Guanxu Pan Youhe Zhou Xiaojing Liu School of Management Science and Engineering Anhui University of Finance and EconomicsBengbu233030China Key Laboratory of Mechanics on Disaster and Environment in Western China The Ministry of EducationCollege of Civil Engineering and MechanicsLanzhou UniversityLanzhou730000China

In this study,a wavelet multi-resolution interpolation Galerkin method(WMIGM)is proposed to solve linear singularly perturbed boundary value problems.Unlike conventional wavelet schemes,the proposed algorithm can be readily extended to special node generation techniques,such as the Shishkin node.Such a wavelet method allows a high degree of local refinement of the nodal distribution to efficiently capture localized steep gradients.All the shape functions possess the Kronecker delta property,making the imposition of boundary conditions as easy as that in the finite element method.Four numerical examples are studied to demonstrate the validity and accuracy of the proposedwavelet method.The results showthat the use ofmodified Shishkin nodes can significantly reduce numerical oscillation near the boundary layer.Compared with many other methods,the proposed method possesses satisfactory accuracy and efficiency.The theoretical and numerical results demonstrate that the order of theε-uniform convergence of this wavelet method can reach 5.

关键词： Wavelet multi-resolution interpolation Galerkin singularly perturbed boundary value problems mesh-free method Shishkin node boundary layer

A mesh-free ALGORITHM FOR DYNAMIC IMPACT ANALYSIS OF HYPERELASTICITY

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2013年第4期26卷 362-372页

作者： De’an Hu Zhanhua Sun Chao Liang Xu Han State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan University

A mesh-free method based on local Petrov-Galerkin formulation is presented to solve dynamic impact problems of hyperelastic material.In the present method,a simple Heaviside test function is chosen for simplifying domain integrals.Trial function is constructed by using a radial basis function （RBF） coupled with a polynomial basis function,in which the shape function possesses the kronecker delta function property.So,additional treatment is not required for imposing essential boundary conditions.Governing equations of impact problems are established and solved node by node by using an explicit time integration algorithm in a local domain,which is very similar to that of the collocation method except that numerical integration can be implemented over local domain in the present method.Numerical results for several examples show that the present method performs well in dealing with the dynamic impact problem of hyperelastic material.

关键词： mesh-free method dynamic impact problem hyperelasticity explicit algorithm

维普期刊数据库

meshless methods Coupled with Other Numerical methods

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2005年第1期10卷 8-15页

作者： Y.T.GU G.R.LIU CentreforAdvancedComputationsinEngineeringScience(ACES) DepartmentofMechanicalEngineeringNationalUniversityofSingapore10KentRidgeCrescentSingapore119260Singapore

meshless or mesh-free (or shorten as Mfree) methods have been proposed and achieved remarkable progress over the past few years. The idea of combining Mfree methods with other existing numerical techniques such as the finite element method (FEM) and the boundary element method (BEM), is naturally of great interest in many practical applications. However, the shape functions used in some Mfree methods do not have the Kronecker delta function property. In order to satisfy the combined conditions of displacement compatibility, two numerical techniques, using the hybrid displacement shape function and the modified variational form, are developed and discussed in this paper. In the first technique, the original Mfree shape functions are modified to the hybrid forms that possess the Kronecker delta function property. In the second technique, the displacement compatibility is satisfied via a modified variational form based on the Lagrange multiplier method. Formulations of several coupled methods are presented. Numerical exam- ples are presented to demonstrate the effectiveness of the present coupling methods.

关键词： meshless method mesh-free method finite element method boundary element method coupling method stress analysis

维普期刊数据库

A Gravity Forward Modeling method based on Multiquadric Radial Basis Function

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2021年第S1期95卷 62-64页

作者： LIU Yan LV Qingtian HUANG Yao SHI Danian MENG Guixiang YAN Jiayong ZHANG Yongqian China Deep Exploration Center-SinoProbe Center Chinese Academy of Geological SciencesBeijing 100037China China University of Geosciences Wuhan 430074China

It is one of the most important part to build an accurate gravity model in geophysical exploration.Traditional gravity modelling is usually based on grid method,such as difference method and finite element method wide... 详细信息

关键词： geophysical exploration gravity forward modeling mesh-free method radial basis function

维普期刊数据库

mesh-free SIMULATION FOR COMPRESSION AND TWISTING BUCKLING OF SWCNTS USING HIGHER ORDER CAUCHY-BORN RULE

在线全文

学校读者我要写书评

暂无评论

MESH-FREE SIMULATION FOR COMPRESSION AND TWISTING BUCKLING O...