Anupam Krishnan¹, Anjana P. Anantharaman^2,*

Molecular & Cellular Biomechanics, Vol.19, No.2, pp. 77-88, 2022, DOI:10.32604/mcb.2022.018369

Abstract Computational Fluid Dynamics has become relevant in the study of hemodynamics, where clinical results are challenging to obtain. This paper discusses a 2-Dimensional transient blood flow analysis through an arterial bifurcation for patients infected with the Coronavirus. The geometry considered is an arterial bifurcation with main stem diameter 3 mm and two outlets. The left outlet (smaller) has a diameter of 1.5 mm and the right outlet (larger), 2 mm. The length of the main stem, left branch and right branch are fixed at 35 mm, 20 mm and 25 mm respectively. Viscosity change that occurs in the blood leads… More >

Mahmoud H. Taha¹, Mohamed A. Ramadan^2,*, Dumitru Baleanu^3,4,5, Galal M. Moatimid¹

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 969-983, 2020, DOI:10.32604/cmes.2020.010942

Abstract The current paper is concerned with a modified Homotopy perturbation technique. This modification allows achieving an exact solution of an initial value problem of the fractional differential equation. The approach is powerful, effective, and promising in analyzing some classes of fractional differential equations for heat conduction problems and other dynamical systems. To crystallize the new approach, some illustrated examples are introduced. More >

Farnaz Ismail¹, Mubashir Qayyum^{2, *}, Syed Inayat Ali Shah¹

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 825-845, 2020, DOI:10.32604/cmes.2020.011073

Abstract Modeling and analysis of thin film flow with respect to magneto hydro dynamical effect has been an important theme in the field of fluid dynamics, due to its vast industrial applications. The analysis involves studying the behavior and response of governing equations on the basis of various parameters such as thickness of the film, film surface profile, shear stress, liquid velocity, volumetric flux, vorticity, gravity, viscosity among others, along with different boundary conditions. In this article, we extend this analysis in fractional space using a homotopy based scheme, considering the case of a Non-Newtonian Pseudo-Plastic fluid for lifting and drainage… More >

Z. Neffah¹, H. Kahalerras^{1, *}, B. Fersadou¹

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.1, pp. 39-56, 2018, DOI:10.3970/fdmp.2018.014.039

Abstract A numerical study of heat and mass transfer in a non-Newtonian fluid in a parallel-plate channel partly filled with an anisotropic porous medium and subjected to an exothermic chemical reaction on its walls has been conducted. The flow field in the porous region has been modeled by the modified Brinkman-Forchheimer extended Darcy model for power-law fluids and a finite volume method has been used to solve the governing equations. The influence played by a variation of the anisotropic ratio on thermal conductivity, power-law index, Darcy number, and chemical reaction characteristics has been examined. We show that the anisotropy of a… More >

P. Jhunjhunwala^∗,†, P.M. Padole^∗,‡, S.B. Thombre^∗,§

Molecular & Cellular Biomechanics, Vol.12, No.1, pp. 37-47, 2015, DOI:10.3970/mcb.2015.012.037

Abstract CFD analysis plays an important role in the area of analysis of blood flow as in-vivo measurements of blood flow is costly and easily not accessible. This paper presents simulation of blood flow in healthy and stenosed coronary artery 2- D models. The simulation was done considering non-Newtonian behavior of blood and pulsatile nature of blood flow which is close to physical scenario. Pressure distribution, velocity distribution and wall shear were examined to understand their effect on Atherosclerosis. More >

T. Zhang^*

Molecular & Cellular Biomechanics, Vol.8, No.3, pp. 169-194, 2011, DOI:10.3970/mcb.2011.008.169

Abstract Cytoplasmic motion assumed as a steady state laminar flow induced by cytoskeleton stretching in a cell is determined and its effect on the mechanical behavior of the cell under externally applied forces is demonstrated. Non-Newtonian fluid is assumed for the multiphase cytoplasmic fluid and the analytical velocity field around the macromolecular chain is obtained by solving the reduced nonlinear momentum equation using homotopy technique. The entropy generation by the fluid internal friction is calculated and incorporated into the entropic elasticity based 8-chain constitutive relations. Numerical examples showed strengthening behavior of cells in response to externally applied mechanical stimuli. The spatial… More >

S.-C. Hsiao¹, M.S. Ingber²

CMC-Computers, Materials & Continua, Vol.1, No.1, pp. 51-58, 2004, DOI:10.3970/cmc.2004.001.051

Abstract The lateral migration of nonneutrally-buoyant spherical particles in Poiseuille flow is investigated numerically using the boundary element method. In particular, the steady, Navier-Stokes equations are solved using a classical domain integration method treating the nonlinear terms as pseudo-body forces. The numerical results for the lateral migration velocity are compared with experimental data. The numerical results indicate that the lateral migration velocity does not scale linearly with the Reynolds number. The methodology is extended to include non-Newtonian power-law fluids. The migration velocity is significantly affected for particles suspended in this class of fluids and can actually change direction for large values… More >

F. Wang¹, J.L. Li¹, B.X. Yang¹, N.A. Hill²

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.1, pp. 59-85, 2013, DOI:10.3970/cmes.2013.095.059

Abstract A gas-liquid two-phase model for the simulation of a power-law fluid mold filling process with the consideration of phase change is proposed, in which the governing equations for the melt and air in the cavity, including the mass conservation, momentum conservation and energy conservation equations, are unified into one system of equation. A revised Enthalpy method, which can be used for both the melt and air in the mold cavity, is proposed to describe the phase change during the mold filling. Finite volume method on non-staggered grid is used to solve the system. The level set method is used to… More >

K.Y. Volokh^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.1, pp. 87-101, 2013, DOI:10.3970/cmes.2013.092.087

Abstract In the laminar mode interactions among molecules generate friction between layers of water that slide with respect to each other. This friction triggers the shear stress, which is traditionally presumed to be linearly proportional to the velocity gradient. The proportionality coefficient characterizes the viscosity of water. Remarkably, the standard Navier-Stokes model surmises that materials never fail – the transition to turbulence can only be triggered by some kinematic instability of the flow. This premise is probably the reason why the Navier-Stokes theory fails to explain the so-called subcritical transition to turbulence with the help of the linear instability analysis. When… More >

G. Kosec¹, B. Šarler²

CMES-Computer Modeling in Engineering & Sciences, Vol.47, No.2, pp. 191-216, 2009, DOI:10.3970/cmes.2009.047.191

Abstract This paper explores an application of a novel mesh-free Local Radial Basis Function Collocation Method (LRBFCM) [Sarler and Vertnik (2006)] in solution of coupled heat transfer and fluid flow problems with solid-liquid phase change. The melting/freezing of a pure substance is solved in primitive variables on a fixed grid with convection suppression, proportional to the amount of the solid fraction. The involved temperature, velocity and pressure fields are represented on overlapping sub-domains through collocation by using multiquadrics Radial Basis Functions (RBF). The involved first and second derivatives of the fields are calculated from the respective derivatives of the RBF's. The… More >