Many mathematical models involve flow equations characterized by nonconstant viscosity, and a Stokes-type problem with variable viscosity coefficient arises. Appropriate block diagonal preconditioners for the resulting algebraic saddle point linear system produce well-clustered spectra, except for a few interior isolated eigenvalues which may tend to approach zero. These outliers affect the con...

The steady mixed convection boundary layer flow near the lower stagnation point of a solid sphere, generated by Newtonian heating in which the heat transfer from the surface is proportional to the local surface temperature, is considered in this study. The governing boundary layer equations are first transformed into a system of non-dimensional equations via the non-dimensional variables, and t...

Optimal graft design has been an objective of many researchers to find correlations between hemodynamics and graft failure. Compared to planar grafts, the helical graft configurations improve hemodynamic performance including the promotion of flow mixing and reduction of flow stagnation regions. In order to evaluate the advantages and disadvantages of the suggested helical type bypass graft mod...

−− The transformation group theoretic approach is applied to the system of equations governing the unsteady boundary layer flow of a micropolar fluid near the rear stagnation point of a plane surface in a porous media. The application of a two-parameter group reduces the number of independent variables by two, and consequently the system of governing partial differential equations with boundary...

The main aim of this study was to determine the kinetic energy and momentum coefficients of a small trapezoidal irrigation canal. A laboratory setup with a cyclic flow of water was used. The flow cross section was divided into ten equal sections with nine verticals in between. Pitot static tube was used to measure static and stagnation pressure heads at 1, 2, 3, 4, 5, or 6 point on the vertical...

BACKGROUND Intra-arterial treatment of aneurysms by redirecting blood flow is a newer method. The redirection is based on a significantly more densely braided wire stent. The stent wall keeps the blood in the lumen of the stent and slows down the turbulent flow in the aneurysms. Stagnation of blood in the aneurysm sac leads to the formation of thrombus and subsequent exclusion of the aneurysm f...

The objective of this study is to fully characterize the flow within the HeartQuest ventricular assist device (VAD), a magnetically levitated centrifugal VAD, using particle image velocimetry (PIV) to identify regions of potential high shear or stagnation and validate and refine computational models of the flow. An acrylic model of the pump was designed and constructed to allow optical access i...

The aim of this project is to make up a comprehensive model of the dynamics and evolution of the Earth's mantle, and to simulate phenomena related with subduction. (1) With the global modeling in Earth-like spherical shell geometry, we made systematic research on the convection patterns for the wide range of Rayleigh numbers with phase transitions. The experimentally and seismologically plausib...

The steady, two dimensional flow of an incompressible micropolar fluid near the stagnation point on a vertical plate with prescribed surface heat flux is studied. The free stream velocity and the surface heat flux are assumed to be proportional to the distance from the stagnation point. Similarity transformation is employed to transform the governing partial differential equations to a set of o...