Longling Fan^1,*, Jing Yao ^{2, *}, Chun Yang³, Di Xu², Dalin Tang^{1, 4, §}

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.2, pp. 221-237, 2018, DOI:10.3970/cmes.2018.114.221

Abstract Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions. Patient-specific Echo-based left ventricle (LV) fluid-structure interaction (FSI) models were introduced to perform ventricle mechanical analysis, investigate flow behaviors, and evaluate the impact of myocardial infarction (MI) and hypertension on blood flow in the LV. Echo image data were acquired from 3 patients with consent obtained: one healthy volunteer (P1), one hypertension patient (P2), and one patient who had an inferior and posterior myocardial infarction (P3). The nonlinear Mooney-Rivlin model was used for ventricle tissue with material parameter values chosen to match echo-measure… More >

B. Liu¹, D. Tang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.2, pp. 55-60, 2011, DOI:10.3970/icces.2011.017.055

Abstract The effects of the non-Newtonian blood viscosity on the wall shear stress (WSS) of the blood flows in stenotic right coronary arteries have been investigated by computer simulations. The numerical calculations were performed using the Newtonian Model and the non-Newtonian models with the fluid obeying the Power Law and the Carreau models for the simulations of unsteady blood flows. The differences on the spatial and temporal WSS distribution patterns due to the different blood properties were compared. The computational results demonstrate that the blood viscosity properties do not affect the spatial WSS distribution pattern qualitatively. The region on the inner… More >

T. Ishikawa¹, H. Fujiwara¹, N. Matsuki², R. Lima³, Y. Imai¹, T. Yamaguchi²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 77-78, 2009, DOI:10.3970/icces.2009.009.077

Abstract In a small artery, the blood is no longer assumed as a homogeneous fluid, because the size of blood cells cannot be neglected compared to the generated flow field. In such a case, we need to treat the blood as a multi-phase fluid, and investigate the motion of individual cells in discussing the flow field. Blood may be modelled as a suspension of red blood cells (RBCs) in plasma, because about 99% of volume fraction of blood cells is RBCs.
In order to measure a blood flow experimentally, various methods have been employed. However, most of conventional techniques are difficult… More >

Gaiping Zhao¹, Feiyi Xia¹, Eryun Chen², Xiaoli Yu³, Zhaozhi Yang^3,*

Molecular & Cellular Biomechanics, Vol.14, No.1, pp. 47-57, 2017, DOI:10.3970/mcb.2017.014.049

Abstract Metastatic tumor blood perfusion and interstitial fluid transport based on 3D microvasculature response to inhibitory effect of angiostatin are investigated in this paper. 3D blood flow、interstitial fluid transport and transvascular flow are described by the extended Poiseuille’s, Darcy’s and Starling’s law, respectively. Numerical solutions reveal that angiostatin can promote improved blood perfusion and decrease elevated interstitial fluid pressure within the metastatic tumor microenvironment. Moreover, angiostatin can increase interstitial convection within the tumor and result in more efficient drug delivery and penetration within the metastatic tumor, which suits well with the experimental observations. Together, our results may provide therapeutic implications for… More >

PoojaJhunjhunwala¹, P.M. Padole², S.B. Thombre³

Molecular & Cellular Biomechanics, Vol.13, No.1, pp. 1-21, 2016, DOI:10.3970/mcb.2016.013.001

Abstract This paper presents Computational fluid dynamic (CFD) analysis of blood flow in three different 3-D models of left coronary artery (LCA). A comparative study of flow parameters (pressure distribution, velocity distribution and wall shear stress) in each of the models is done for a non-Newtonian (Carreau) as well as the Newtonian nature of blood viscosity over a complete cardiac cycle. The difference between these two types of behavior of blood is studied for both transient and steady states of flow. Additionally, flow parameters are compared for steady and transient boundary conditions considering blood as non-Newtonian fluid. The study shows that… More >

M. Moatamedi^∗, M. Souli^†, E. Al-Bahkali^‡

Molecular & Cellular Biomechanics, Vol.11, No.4, pp. 221-234, 2014, DOI:10.3970/mcb.2014.011.221

Abstract This paper describes the capabilities of fluid structure interaction based multi-physics numerical modelling in solving problems related to vascular biomechanics. In this research work, the onset of a pressure pulse was simulated at the entrance of a three dimensional straight segment of the blood vessel like circular tube and the resulting dynamic response in the form of a propagating pulse wave through the wall was analysed and compared. Good agreement was found between the numerical results and the theoretical description of an idealized artery. Work has also been done on implementing the material constitutive models specific for vascular applications. More >

Wei Huang^∗, Jun Shi^†, R. T. Yen^†,‡

Molecular & Cellular Biomechanics, Vol.9, No.4, pp. 269-284, 2012, DOI:10.3970/mcb.2012.009.269

Abstract The objective of our study was to develop a computing program for computing the transit time frequency distributions of red blood cell in human pulmonary circulation, based on our anatomic and elasticity data of blood vessels in human lung. A stochastic simulation model was introduced to simulate blood flow in human pulmonary circulation. In the stochastic simulation model, the connectivity data of pulmonary blood vessels in human lung was converted into a probability matrix. Based on this model, the transit time of red blood cell in human pulmonary circulation and the output blood pressure were studied. Additionally, the stochastic simulation… More >

Biyue Liu^∗, Dalin Tang^†

Molecular & Cellular Biomechanics, Vol.8, No.1, pp. 73-90, 2011, DOI:10.3970/mcb.2011.008.073

Abstract The objective of this work is to investigate the effect of non-Newtonian properties of blood on the wall shear stress (WSS) in atherosclerotic coronary arteries using both Newtonian and non-Newtonian models. Numerical simulations were performed to examine how the spatial and temporal WSS distributions are influenced by the stenosis size, blood viscosity, and flow rate. The computational results demonstrated that blood viscosity properties had considerable effect on the magnitude of the WSS, especially where disturbed flow was observed. The WSS distribution is highly non-uniform both temporally and spatially, especially in the stenotic region. The maximum WSS occurred at the proximal… More >

Bhaskar Chandra Konala^∗, Ashish Das^∗, Rupak K Banerjee^∗,†

Molecular & Cellular Biomechanics, Vol.8, No.1, pp. 1-20, 2011, DOI:10.3970/mcb.2011.008.001

Abstract Hemodynamic endpoints such as flow and pressure drop are often measured during angioplasty procedures to determine the functional severity of a coronary artery stenosis. There is a lack of knowledge regarding the influence of compliance of the arterial wall-stenosis on the pressure drop under hyperemic flows across coronary lesions. This study evaluates the influence in flow and pressure drop caused by variation in arterial-stenosis compliance for a wide range of stenosis severities. The flow and pressure drop were evaluated for three different severities of stenosis and tested for limiting scenarios of compliant models. The Mooney-Rivlin model defined the non-linear material… More >

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 >