Haoyu Wan, Heng Zhang, Zhizhu He^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 639-651, 2021, DOI:10.32604/fdmp.2021.012106

Abstract Treating coronary bifurcation stenosis is still a challenging task. Existing procedures still display a relatively small rate of success. This paper aims to investigate numerically the effect of bifurcation lesions with different structures on the dynamics of blood flow and related temperature. The problem geometry is parametrically varied by changing the bifurcation angle and radius. A finite volume method is used to simulate the three-dimensional flow. The effects induced by the structure of the stenosis, the artery bifurcation angle and radius, and the inlet velocity of blood are discussed in terms of flow pattern, pressure distribution, and shear stress at… More >

Yuanliang Tang^{1, 2}, Lizhong Mu¹, Ying He^{1, *}

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.2, pp. 281-296, 2020, DOI:10.32604/fdmp.2020.06760

Abstract The aim of this study is to develop a model of fluid and heat transfer in a biological tissue taking into account the exact structure of the related microvascular network, and to analyze the influence of structural changes of such a network induced by diabetes. A cubic region representing local skin tissue is selected as the computational domain, which in turn includes two intravascular and extravascular sub-domains. To save computational resources, the capillary network is reduced to a 1D pipeline model and embedded into the extravascular region. On the basis of the immersed boundary method (IBM) strategy, fluid and heat… More >

B. Mochnacki¹, E. Majchrzak²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.3&4, pp. 431-438, 2003, DOI:10.3970/cmes.2003.004.431

Abstract In the paper the analysis of transient temperature field in the domain of biological tissue subjected to an external heat source is presented. Because of the geometrical features of the skin the heat exchange in domain considered is assumed to be one-dimensional. The thermophysical parameters of successive skin layers (dermis, epidermis and sub-cutaneous region) are different, at the same time in sub-domains of dermis and sub-cutaneous region the internal heat sources resulting from blood perfusion are taken into account. The degree of the skin burn results from the value of the so-called Henriques integrals. The first and the second order… More >

Bohdan Mochnacki¹, Grażyna Kaluża²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.1, pp. 15-20, 2007, DOI:10.3970/icces.2007.001.015

Abstract This article has no abstract. More >

Ewa Majchrzak^*

Molecular & Cellular Biomechanics, Vol.10, No.3, pp. 201-232, 2013, DOI:10.3970/mcb.2013.010.201

Abstract Heat transfer processes proceeding in the living organisms are described by the different mathematical models. In particular, the typical continuous model of bioheat transfer bases on the most popular Pennes equation, but the Cattaneo-Vernotte equation and the dual phase lag equation are also used. It should be pointed out that in parallel are also examined the vascular models, and then for the large blood vessels and tissue domain the energy equations are formulated separately. In the paper the different variants of the boundary element method as a tool of numerical solution of bioheat transfer problems are discussed. For the steady… More >

Marek Jasiński^*

Molecular & Cellular Biomechanics, Vol.10, No.3, pp. 183-199, 2013, DOI:10.3970/mcb.2013.010.183

Abstract In the paper the numerical analysis of thermal processes proceeding in the biological tissue is presented. The tissue is subjected to the external heat flux and 2D problem is taken into account. In order to determine the influence of variations of thermophysical parameters of tissue on the value of Arrhenius injury integral the direct approach of sensitivity analysis is applied. On the basis of tissue damage fraction the thermal injury formation process is analysed. At the stage of numerical realization the boundary element method is used. In the final part of the paper the example of numerical simulation is shown. More >

Ze-Wei Zhang^*, Hui Wang^†, Qing-Hua Qin^∗,‡

Molecular & Cellular Biomechanics, Vol.9, No.1, pp. 31-54, 2012, DOI:10.3970/mcb.2012.009.031

Abstract This paper presents a hybrid finite element model for describing quantitatively the thermal responses of skin tissue under laser irradiation. The model is based on the boundary integral-based finite element method and the Pennes bioheat transfer equation. In this study, temporal discretization of the bioheat system is first performed and leads to the well-known modified Helmholtz equation. A radial basis function approach and the boundary integral based finite element method are employed to obtain particular and homogeneous solutions of the laser-tissue interaction problem. In the boundary integral based finite element formulation, two independent fields are assumed: intra-element field and frame… More >

Ewa Majchrzak¹

CMES-Computer Modeling in Engineering & Sciences, Vol.69, No.1, pp. 43-60, 2010, DOI:10.3970/cmes.2010.069.043

Abstract Heat transfer processes proceeding in domain of heating tissue are discussed. The typical model of bioheat transfer bases, as a rule, on the well known Pennes equation, this means the heat diffusion equation with additional terms corresponding to the perfusion and metabolic heat sources. Here, the other approach basing on the dual-phase-lag equation (DPLE) is considered in which two time delays τ_q, τ_T (phase lags) appear. The DPL equation contains a second order time derivative and higher order mixed derivative in both time and space. This equation is supplemented by the adequate boundary and initial conditions. To solve the problem… More >