Mechanical Engineering Commons^™

Background And Available Potential Energy In Numerical Simulations Of A Boussinesq Fluid, Shreyas S. Panse

Masters Theses 1911 - February 2014

In flows with stable density stratification, a portion of the gravitational potential energy is available for conversion to kinetic energy. The remainder is not and is called “background potential energy”. The partition of potential energy is analogous to the classical division of energy due to motion into its kinetic and internal components. Computing background and available potential energies is important for understanding stratified flows. In many numerical simulations, though, the Boussinesq approximations to the Navier-Stokes equations are employed. These approximations are not consistent with conservation of energy. In this thesis we re-derive the governing equations for a buoyancy driven fluid …

The Effect Of Leaves And Steel Support Cables On The Dynamic Properties Of Northern Red Oak (Quercus Rubra) With Co-Dominant Trunks, Mark Reiland

Masters Theses 1911 - February 2014

Natural frequency and damping ratio were measured for ten forest grown northern red oak trees with co-dominant trunks. Steels support cables were installed in the canopies of five of the sample trees prior to measurement. Free vibration testing was performed during periods when leaves were and were not present. An accelerometer mounted at the base of the co-dominant union measured the acceleration time history during the free vibration testing. Natural frequency was determined from the acceleration time history using power spectral density analysis. Damping ratios were calculated from the power spectral density plots using the half power bandwidth method.

Trees …