Many industries have chimneys for ventilation of exhaust gases or smoke produced by a furnace, boiler, etc. Due to their height, the external air flowing over these tall chimneys exert aerodynamic forces on them. The structural integrity of these chimneys is, therefore, very important. When the airflow passes over the chimney at a low Reynolds number, the flow is symmetric. As the Reynolds number of the flow increases, the flow field becomes asymmetric, leading to the creation of periodic vortex structures in the flow. These are called Von Karman Vortices, and they detach periodically from the body creating a repeating pattern of swirling vortices behind it. When the frequency of these vortices matches the resonance frequency of these tall structures, it can induce violent oscillations in the structure that might damage or, worse, destroy the chimney. In this Sim Café example, we will consider the canonical problem of unsteady flow past a cylinder to understand the aerodynamic effects of wind on chimneys.
This SimCafe Course was developed by Dr. Rajesh Bhaskaran, Swanson Director of Engineering Simulation at Cornell University, and John Singleton Jr in partnership with Ansys. It serves as an e-learning resource to integrate industry-standard simulation tools into courses and provides a resource for supplementary learning outside the classroom. In this tutorial, we will learn about the CFD analysis of vortex shedding using Ansys Fluent.
For more ways to learn, check out the Cornell edX course, A Hands-on Introduction to Engineering Simulations at ansys.com/cornell.
Cornell University also offers a Fluid Dynamics Simulations Using Ansys online certificate authored by Dr. Rajesh Bhaskaran. Learn more here: https://ecornell.cornell.edu/fluiddynamics