Biyue Liu^∗, Dalin Tang^†

Molecular & Cellular Biomechanics, Vol.7, No.4, pp. 193-202, 2010, DOI:10.3970/mcb.2010.007.193

Abstract A three dimensional mathematical model with a linear plaque growth function was developed to investigate the geometrical adaptation of atherosclerotic plaques in coronary arteries and study the influences of flow wall shear stress (WSS), blood viscosity and the inlet flow rate on the growth of atherosclerotic plaques using computational plaque growth simulations. The simulation results indicated that the plaque wall thickness at the neck of the stenosis increased at a decreasing rate in the atherosclerosis progression. The simulation results also showed a strong dependence of the plaque wall thickness increase on the blood viscosity and the inlet flow rate. The… More >

Mohammad Mashayekhi¹, Hossein M. Shodja^1,2, Reza Namakian¹

CMES-Computer Modeling in Engineering & Sciences, Vol.76, No.1, pp. 19-60, 2011, DOI:10.3970/cmes.2011.076.019

Abstract A meshless method called reproducing kernel particle method (RKPM) is exploited to cope with elastic-plastic fracture mechanics (EPFM) problems. The idea of arithmetic progression is assumed to place particles within the refinement zone in the vicinity of the crack tip. A comparison between two conventional treatments, visibility and diffraction, to crack discontinuity is conducted. Also, a tracking to find the appropriate diffraction parameter is performed. To assess the suggestions made, two mode I numerical simulations, pure tension and pure bending tests, are executed. Results including J integral, crack mouth opening displacement (CMOD), and plastic zone size and shape are compared… More >

Chun Yang^1,2, Dalin Tang², Satya Atluri³

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.1, pp. 53-78, 2011, DOI:10.3970/cmes.2011.072.053

Abstract Previously, we introduced a computational procedure based on three-dimensional meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data to quantify patient-specific carotid atherosclerotic plaque growth functions and simulate plaque progression. Structure-only models were used in our previous report. In this paper, fluid-stricture interaction (FSI) was added to improve on prediction accuracy. One participating patient was scanned three times (T1, T2, and T3, at intervals of about 18 months) to obtain plaque progression data. Blood flow was assumed to laminar, Newtonian, viscous and incompressible. The Navier-Stokes equations with arbitrary Lagrangian-Eulerian (ALE) formulation were used as the governing… More >

Chun Yang^1,2, Dalin Tang^2,3 Satya Atluri⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.57, No.1, pp. 51-76, 2010, DOI:10.3970/cmes.2010.057.051

Abstract Cardiovascular disease (CVD) is becoming the number one cause of death worldwide. Atherosclerotic plaque rupture and progression are closely related to most severe cardiovascular syndromes such as heart attack and stroke. Mechanisms governing plaque rupture and progression are not well understood. A computational procedure based on three-dimensional meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data was introduced to quantify patient-specific carotid atherosclerotic plaque growth functions and simulate plaque progression. Participating patients were scanned three times (T1, T2, and T3, at intervals of about 18 months) to obtain plaque progression data. Vessel wall thickness (WT) changes… More >

Chun Yang¹, Dalin Tang², Chun Yuan³, William Kerwin², Fei Liu³, Gador Canton³, Thomas S. Hatsukami^3,4, Satya Atluri⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.28, No.2, pp. 95-108, 2008, DOI:10.3970/cmes.2008.028.095

Abstract Atherosclerotic plaque rupture and progression have been the focus of intensive investigations in recent years. Plaque rupture is closely related to most severe cardiovascular syndromes such as heart attack and stroke. A computational procedure based on meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data was introduced to quantify patient-specific carotid atherosclerotic plaque growth functions and simulate plaque progression. Participating patients were scanned three times (T₁,T₂, and T₃, at intervals of about 18 months) to obtain plaque progression data. Vessel wall thickness (WT) changes were used as the measure for plaque progression. Since there was insufficient… More >

R. Han¹, M.S. Ingber¹, H.L. Schreyer¹

CMC-Computers, Materials & Continua, Vol.4, No.3, pp. 163-176, 2006, DOI:10.3970/cmc.2006.004.163

Abstract Decohesion is an important failure mode associated with fiber-reinforced composite materials. Analysis of failure progression at the fiber-matrix interfaces in fiber-reinforced composite materials is considered using a softening decohesion model consistent with thermodynamic concepts. In this model, the initiation of failure is given directly by a failure criterion. Damage is interpreted by the development of a discontinuity of displacement. The formulation describing the potential development of damage is governed by a discrete decohesive constitutive equation. Numerical simulations are performed using the direct boundary element method. Incremental decohesion simulations illustrate the progressive evolution of debonding zones and the propagation of cracks… More >