Contact between deformable bodies is a dif- cult problem in the analysis of engineering systems. A new approach to contact has been implemented us- ing Material Point Method for solid mechanics, Bar- denhagen, Brackbill, and Sulsky (2000a). Here two im- provements algorithm are described. The rst include normal traction logic more appropriately determine free separation crite- rion. second provide numerical stability by scaling impulse when computational grid in- formation suspect, condition...

SUMMARY Convected particle domain interpolation (CPDI) is a recently developed extension of the material point method, in which shape functions on overlay grid are replaced with alternative functions, (by coupling underlying topology) facilitate efficient and algorithmically straightforward evaluation node integrals weak formulation governing equations. In original CPDI algorithm, herein called CPDI1, domains tracked as parallelograms 2‐D (or parallelepipeds 3‐D). this paper, method enhanced...

Angiogenesis is regulated by the local microenvironment, including mechanical interactions between neovessel sprouts and extracellular matrix (ECM). However, mechanisms controlling relationship of biophysical properties ECM to growth during sprouting angiogenesis are just beginning be understood. In this research, we characterized density microvascular topology in an vitro 3D organ culture model angiogenesis. We used these results design calibrate a computational demonstrate how changes...

Abstract An implicit integration strategy was developed and implemented for use with the material point method (MPM). incremental‐iterative solution around Newton's to solve equations of motion Newmark update kinematic variables. Test problems directly compared MPM solutions those obtained using an explicit code finite element (FE) code. Results demonstrated very good agreement FE predictions also illustrated several advantages in comparison calculations In particular, accuracy superior when...

The Material Point Method (MPM) has shown itself to be a powerful tool in the sim- ulation of large deformation problems, especially those involving complex geometries and contact where typical finite element type methods fre- quently fail. While these problems lead some impressive simulations solu- tions, there been lack basic analysis char- acterizing errors present method, even on simplest problems. number choices one when implementing suchas thechoiceofbasisfunctionsandboundary...

This paper reformulates the axisymmetric form of material point method (MPM) using generalized interpolation (GIMP) methods. The reformulation led to a need for new shape functions and gradients specific axisymmetry that were not available before. differ most from planar near origin where r = 0. A second purpose this was evaluate consequences on variety MPM extensions have been developed since original work MPM. These included convected particle domain integration (CPDI), traction boundary...

Understanding the factors that control extent of tissue damage as a result material failure in soft tissues may provide means to improve diagnosis and treatment injuries. The objective this research was develop test computational framework for study anisotropic subjected finite deformation. An constitutive model incorporating strain-based criteria implemented an existing solid mechanics software based on point method (MPM), quasi-meshless particle simulations mechanics. formulations were...

An experimental study of water flow in a T-shaped channel with rectangular cross section (20×20 mm2 inlet ID and 20×40 outlet ID) has been conducted for Reynolds number Re range based on geometry Re=56–422. Dynamical conditions T-channel the current are applicable to microscale. This supports large body numerical work, resolution interrogation region extended beyond previous studies. Laser induced fluorescence (LIF) permits detailed look at fields that evolve over broad where realistic...

AbstractRecent interest in the process of vascularisation within biomedical community has motivated numerous new research efforts focusing on angiogenesis. Although role chemical factors during angiogenesis been well documented, mechanical factors, such as interaction between angiogenic vessels and extracellular matrix, remains poorly understood. In vitro methods for studying exist; however, measurements available using techniques often suffer from limited spatial temporal resolutions. For...

Summary The material point method is well suited for large‐deformation problems in solid mechanics but requires modification to avoid cell‐crossing errors as extension instabilities that lead numerical (nonphysical) fracture. A promising solution convected particle domain interpolation (CPDI), which the integration used map data between particles and background grid deforms with particle, based on deformation gradient. While eliminating instability can be a benefit, it often desirable allow...

The standard velocity projection scheme for the Material Point Method (MPM) and a typical form of GIMP are exam­ ined. It is demonstrated that fidelity in­ formation transfer from particle representation to computational grid strongly dependent on density location. In addition, use non-uniform grids even par­ ticle sizes shown introduce error. An en­ hancement operation devel­ oped which makes already available veloc­ ity gradient information. This enhancement facil­ itates exact linear...

Summary Applying the convected particle domain interpolation (CPDI) to material point method has many advantages over original method, including significantly improved accuracy. However, in large deformation regime, CPDI still may not retain expected convergence rate. The paper proposes an enhanced formulation based on least square reconstruction technique. (CPLS) assumes velocity field inside as nonconstant. This is mapped background grid nodes with a moving squares reconstruction. In this...

Abstract Three-dimensional geometric descriptions of microstructure are indispensable to obtain the structure–property relationships snow. Because snow is a random heterogeneous material, it often helpful construct stochastic models that can be used model physical and mechanical properties In present study, Gaussian field-based reconstruction sieved sintered dry-snow sample with grain size less than 1 mm investigated. The one- two-point correlation functions samples as input for model....

Abstract A novel meshfree method is proposed that incorporates features of the material point (MPM) and generalized interpolation (GIMP) methods can be used within an existing MPM/GIMP implementation. Weighted least squares kernel functions are centered at stationary grid nodes to approximate field values gradients. Integration performed over cells background boundaries approximated with implicit surface. The avoids nearest‐neighbor searches while significantly improving accuracy MPM GIMP....