Engineering Commons^™

Entropy-Based Analysis For Application To Highly Compressible Flows, Ethan A. Vogel

Doctoral Dissertations

Matrix normalizations are a critical component of mathematically rigorous aerodynamics analysis, especially where kinematic and thermodynamic behaviors are of interest. Here, a matrix normalization based around the entropy of a perturbation is derived according to the principles of mathematical entropy analysis and using a general definition of entropy amendable to physical phenomena such as thermal nonequilibrium and caloric and thermal imperfection. This normalization is shown to be closely related to the contemporary Chu energy normalization, expanding the range of validity of that normalization and clarifying the details of its interpretation. This relationship provides a basis for deriving other normalizations. Entropy …

Sediment Resting, Entrainment And Depositional Patterns In A Gravel Bed: Connecting Bedload Transport With Turbulence Structure, Micah Alan Wyssmann

Doctoral Dissertations

This research is founded on the consideration that bedload transport in gravel-bed rivers is interrelated in many ways with turbulence structure. As such, the research includes semi-theoretical modeling and open-channel flume experimental studies that improve our understanding of bedload transport by incorporating knowledge about turbulence, in addition to improving our fundamental knowledge about turbulence.

The first study focused on sediment resting time, which is a minimally understood component of sediment virtual velocity. A semi-theoretical model for resting time that considers momentum transfer from near-bed turbulence was developed, calibrated, and verified. The formulation also included parameters that consider sediment size nonuniformity …