FLUID DYNAMIC Analysis of FLOW IN Orbiting Dishes

It is well documented that hemodynamic parameters, especially wall shear stress (WSS), have been shown to play important roles in altering various endothelial cellular responses, intracellular pathways and gene expression, and to have significant impacts on disease progression, such as atherosclerotic plaque development. However, the fluid dynamics in commonly used orbiting cell culture dishes and the effects of the resulting oscillating fluid flow on shear and endothelial cellular responses within the dishes have not previously been accurately determined due to the difficulty in characterizing the complex flow.  WSS in orbiting dishes is oscillatory rather than steady due to the travelling waveform and varies across the surface of the dish at any instant in time. The first part of this effort presents a cfd model which provides complete spatial and temporal resolution of oscillatory WSS over the bottom surface of an orbiting Petri dish throughout the orbital cycle.  The model was reasonably well validated by the limited analytical solution.A dimensional analysis study was then performed to describe flow and shear characteristics as a function of Slope ratio, Froude Number, and Stokes Number, which allows for a significant reduction in the computational effort to characterize flow characteristics in orbiting dishes. Transition points for each parameter were determined for low and hi values of the remaining parameters. The contribution of tangential and radial WSS components across the bottom surface was then determined as a function of each parameter.