Arterioles with a curve shape are normally associated with a slow, blood flow, which led to a consequent emergence of thrombosis. In spite of the practical importance, there are not enough computational models that studied blood flow in very tiny diameters into one efficient framework. This study has addressed the dynamics of blood effects during porous medium and blood recirculation zones. Simulations of blood flow as a porous medium through an elbow artery have been investigated. The arteries have been treated as a porous medium. The blood is supplied with various geometries of arteries, which have different diameters. The outputs from numerical simulations have presented the details of blood flow patterns and the local distribution of blood flow along the artery. The effects of permeability, with respect to the variations in the Reynolds number (Re = 0.1,1 and 5) as well for changing porosity levels has been discussed. The effects due to different vessel diameters on the resultant distribution of velocity inside the vessel have been studied. Results are presented in the form of variations of velocity distributions and local variations of flow rates through the vessel dimensions. Simulations are compared with the available data and a good agreement is found. The study shows to be potentially useful to evaluate the role of porosity and flow conditions when the body is subjected to diseases.

The problem of entropy generation and mixed convection in a nanofluid trapezoidal cavity with an internal solid cylinder is studied numerically using the finite difference method. The bottom wall is thermally insulated while the upper wall slides with uniform velocity from left to right and cooled isothermally. Remainder of these walls are kept adiabatic. Water-based nanofluids with \Al2O3 nanoparticles are chosen for the investigation. The Boussinesq approximation is applicable. The influence of Reynolds number, Richardson number, dimensionless radius of the solid cylinder, location of the solid cylinder and nanoparticles of volume fraction on streamlines, isotherms, isentropic as well as the local and average Nusselt number were investigated. It was found that the location and size of the solid cylinder are important control parameters for optimizing heat transfer and Bejan number within the partially heated trapezoid cavity.