Download or read book The effect of radial wall motion on the velocity field inside a flexible tube conveying a pulsatile flow written by Frank Joseph Raguso and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study presents the experimental velocity data captured inside the rigid and flexible tubes with steady and pulsatile flow. The purpose of this thesis is to understand how the fluid motion interacts with the surrounding walls and internal motion. An experimental setup was modeled on Siemens NX software and built in order to perform experiments. The inner diameter of both the rigid and flexible tube was 22.2 mm. Silica particles were added to the fluid in order to capture the fluid's movement with a high speed camera for Particle lmage Velocimetry processing. These data captured were analyzed in MATLAB, where velocity fields were calculated and graphed. A set of experiments were conducted to confirm that the entrance length in the setup was not sufficient to produce a developed flow. Largest fluctuations in the tube were seen in the case of flexible walls and a 2 second period. The centerline fluctuations for the 2 second period corresponded to approximately 0.0383 m/s, largest fluctuations for the 1 second period corresponded to approximately 0.0247 m/s, and largest fluctuations for the 3 seconds period corresponded to approximately 0.0111 m/s. The maximum velocity fluctuations also corresponded to the largest wall motion seen in the 2 seconds period cases. Wall motion disturbs the velocity profile by adding and removing energy in the flow at the same oscillation as the wall motion. Another mechanism for how a flexible wall can add velocity fluctuations to the flow occurred at the transition between the rigid tube and the flexible tube. At the flexible tube expansions, a natural step formed in the tube material transition region. A backward facing step added additional perturbations in the flow by creating a slug which affected the velocity profile downstream. ln conclusion, flexible walls result in more fluctuations due to the wall motion and the backward facing step.