A new method, herein referred to as Optimal Mode Decomposition (OMD), of finding a linear model to describe the evolution of a fluid flow is presented. The method estimates the linear dynamics of a high-dimensional system which is first projected onto a subspace of a user-defined fixed rank. An iterative procedure is used to find the optimal combination of linear model and subspace that minimis...

Arterial stenosis, for example Atherosclerosis, is one of the most serious forms of arterial disease in the formation of which hemodynamic factors play a significant role. In the present study, a 3-D rigid carotid artery with axisymmetric stenosis with 75% reduction in cross-sectional area is considered. Laminar blood flow is assumed to have both Newtonian and non-Newtonian behavior (generalize...

Vortices are long-lived features of geophysical and laboratory flows. They emerge in free-decay turbulence and govern the long-term evolution of the flow. In 2D flows, two vortices can grow by merger when they are like-signed. The process of vortex merger in 2D flows is well known for a pair of isolated vortices. Nevertheless, in a turbulent field, the velocity field created by neighboring vort...