Meeting Abstract
Many examples exist in biology that involve a complex interaction between a flexible body and a surrounding fluid, such as the deformation of a fish fin, an insect wing, or the expansion and contraction of an arterial wall in response to a pulsing blood flow. Presently, this fluid-structure interaction (FSI) is acutely challenging to measure as separate measurement techniques are typically used for fluid flow measurement (e.g. Tomographic Particle Image Velocimetry [tomo-PIV]) and surface strains (e.g. photogrammetric methods; Digital Image Correlation [DIC]). A combined method incorporating simultaneous measurements would, therefore, be of widespread utility in biology as it would provide a more complete picture of observed phenomena as well as data for validating computational models. We conducted a series of experiments with the aim of developing a turnkey experimental FSI measurement system that combines the techniques of tomo-PIV and DIC. The first experiment focused on measuring the interaction between the pulsing blood flow in an artery and the deformation of a weakened section of the arterial wall simulating a highly-simplified abdominal aortic aneurysm (AAA). This was accomplished with a cast silicone elastomer model and a pulsing flow of glycerine-water fluid. The refractive index of the fluid and structure were matched to eliminate optical distortion. Simultaneous tomo-PIV and DIC measurements were accomplished using four highly sensitive sCMOS cameras to measure the fluid flow while two further cameras synchronously measured the aneurysmal wall deformation.
