Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
Articles 1 - 4 of 4
Full-Text Articles in Physics
A Study Of Flow Separation In Transonic Flow Using Inviscid And Viscous Cfd Schemes, James Andrew Rhodes
A Study Of Flow Separation In Transonic Flow Using Inviscid And Viscous Cfd Schemes, James Andrew Rhodes
Mechanical & Aerospace Engineering Theses & Dissertations
A comparison of flow separation in transonic flows is made using various computational schemes which solve the Euler and the Navier-Stokes equations of fluid mechanics. The flows examined are computed using several simple two-dimensional configurations including a backward facing step and a bump in a channel. Comparison of the results obtained using shock fitting and flux vector splitting methods are presented and the results obtained using the Euler codes are compared to results on the same configurations using a code which solves the Navier-Stokes equations.
On A Moving Boundary Problem Of Transitional Ballistics, Jen-Ing G. Hwang
On A Moving Boundary Problem Of Transitional Ballistics, Jen-Ing G. Hwang
Mathematics & Statistics Theses & Dissertations
A major problem which arises in computer simulation of the firing of a gun weapon is the development of numerical schemes which effectively account for the physics of projectile motion. The chief difficulty is that away from the projectile the calculation is ordinarily accomplished on a fixed numerical grid, whereas due to projectile movement some cells of the grid near the projectile undergo volume changes as the calculation proceeds. A local finite volume scheme is developed which accounts for the expansion or compression of cells fore-and-aft of the projectile. Through the process of numerical experiment, the effectiveness of the scheme …
A Numerical Study Of Three-Dimensional Vortex Breakdown, Robert Edward Spall
A Numerical Study Of Three-Dimensional Vortex Breakdown, Robert Edward Spall
Mechanical & Aerospace Engineering Theses & Dissertations
A numerical simulation of vortex breakdown using the time-dependent Navier-Stokes equations was performed. Unlike previous studies, the numerical algorithm, formulated in terms of the velocity and vorticity, was not restricted to axisymmetric flows. Prototype vortices were parameterized in terms of their Reynolds number and Rossby number. Two cases were studied extensively. In one case, a vortex was imbedded in a uniform free stream. In the other case, the axial velocity of the free stream was decelerated in the streamwise direction. For both cases breakdown occurred when the Rossby number was below a critical value. Vortex lines, particle traces and velocity …
Studies Of Radiation Effects In Three High Polymers, Heidi Rene-Mitchell Ries
Studies Of Radiation Effects In Three High Polymers, Heidi Rene-Mitchell Ries
Physics Theses & Dissertations
Three high polymers, Mylar®, Ultem®, and Kapton®, were irradiated to total doses of 1, 5, and 9.5 gigarad using 1-MeV electrons. The glass transition temperatures (Tg) of the materials before and after irradiation were measured using an AC electrical dissipation factor technique. From the Tg data, it was found that the electron radiation at these total doses results in net chain scissioning in Mylar and net crosslinking in Ultem, while self-mending is predominant in Kapton. The dielectric constant was measured before and after irradiation, but no significant changes due to irradiation were observed. Electron paramagnetic resonance (EPR) …