Date of Award
Corinne S. Lengsfeld, Ph.D.
Computational fluid dynamics, Finite element analysis, Fluid--solid ineraction, Fluid--structure interaction, FSI, Multiphysics modeling
Fluid-structure interaction (FSI) modeling is a method by which fluid and solid domains are coupled together to produce a single result that cannot be produced if each physical domain was evaluated individually. The work presented in this dissertation is a demonstration of the methods and implementation of FSI modeling into an industry-appropriate design tool. Through utilizing computationally inexpensive equipment and commercially available software, the studies presented in this work demonstrate the ability for FSI modeling to become a tool used broadly in industry.
To demonstrate this capability, the cases studied purposely include substantial complexity to demonstrate the stability techniques required for modeling the inherent instabilities of FSI models that contain three-dimensional geometries, nonlinear materials, thin-walled geometries, steep gradients, and transient behavior. The work also modeled scenarios that predict system failure and optimal design to extend service lifetime, thereby expanding upon current FSI literature. Four independent studies were performed, evaluating three separate modes of failure in FSI models, to demonstrate that FSI modeling is a viable design tool for widespread industry use.
The first study validates FSI modeling techniques by comparing the results of a thin-walled FSI geometry model under hydrostatic forces with existing experimental data.
The second study explored a parametric study that evaluated the factors influencing an FSI model containing a highly complex thermal-fluid fatigue model. This model involved dynamically changing temperature loads resulting in significant thermal expansion that led to material yielding and dynamic fatigue life.
The third study evaluated a thermal-fluid conjugate heat transfer problem. The model was tuned, validated, and optimized for lifetime, and the validation of the system was performed using experimental data.
The final study modeled the highly complex fluid and solid phenomena involved in a peristaltic pump where the goal was to demonstrate that the lifetime performance of the tubing could be altered by changing the geometry, material properties, and operating temperature. The model in this final study combined all the methods and techniques from the three earlier studies and applied them to a thin-walled tube geometry with nonlinear and temperature-dependent material properties to create large solid deformation and fluid motion.
Sederstrom, Donn R., "Methods and Implementation of Fluid-Structure Interaction Modeling into an Industry-Accepted Design Tool" (2016). Electronic Theses and Dissertations. 1197.
Received from ProQuest
Donn R. Sederstrom