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Peripheral artery stents are commonly used as an alternative to invasive treatment for atherosclerosis. Design of stents has traditionally relied on structural Finite Element Analysis (FEA). Correct representation of kinematic boundary conditions in FEA models is very important for stent design. Moreover, real-time tracking of stent deformations and subsequent calculations of stresses can be potentially used during the endovascular procedures. The medical imaging data stream can be used for photogrammetric measurements of stent deformations. In this study, a method is proposed to couple FEA stress simulations with real-time image analysis. A customized testing machine was designed and fabricated to apply tension, twisting, and three points bending to various stents. A CCD camera was used to capture stent deflection images at 30 frames per second. Image processing algorithms and code were developed to identify stent boundaries and to measure deformation modes. The obtained deformations were applied as boundary conditions to FEA stent models. Stresses developed at different regions in the stent structure were observed and points of maximum stresses were recorded.

The aerodynamics of a straight edged and a swept edged blade are investigated using a commercial CFD code. RANS equations with SST k-ω equation were utilized to study the flow separation along the blades span in a stall region. The analysis results will be used to provide inputs to future designs to improve and to enable better prediction of the stall region. The computations were carried out in a narrow wind speed range of 14 m/s to 16 m/s which as per earlier analysis was near the stall point to further understand the locations of flow separations along the blade span. The study provides some insights in to the flow physics in the region around the wind turbine blade. An FE Analysis was also performed to further understand the maximum stress and displacement regions to further provide inputs to future designs. A comparison of maximum stress, deformation and structural vibration modes for the two blades were also done.

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