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A Numerical Study of Compressible Lid Driven Cavity Flow with a Moving Boundary
Get PDFA two-dimensional (2-D), mathematical model is adopted to investigate the development of circulation patterns for compressible, laminar, and shear driven flow inside a rectangular cavity. The bottom of the cavity is free to move at a specified speed and the aspect ratio of the cavity is changed from 1.0 to 1.5. The vertical sides and the bottom of the cavity are assumed insulated. The cavity is filled with a compressible fluid with Prandtl number, Pr =1. The governing equations are solved numerically using the commercial Computational Fluid Dynamics (CFD) package ANSYS FLUENT 2015 and compared with the results for the primitive variables of the problem obtained using in house CFD code based on Coupled Modified Strongly Implicit Procedure (CMSIP). The simulations are carried out for the unsteady, lid driven cavity flow problem with moving boundary (bottom) for different Reynolds number, Mach numbers, bottom velocities and high initial pressure and temperature
Supplying the Asia-Pacific Theater: United States Logistics and the American Merchant Marine in World War II
Get PDFAmerica’s victory in World War II came from a number of successes such as production of war materiel, technological advances, and national mobilization on levels not seen before or since. America went into the war behind the Axis Powers both militarily and economically. The Great Depression had a devastating effect on merchant ship building in the United States during the 1930’s. In response, the U.S. Congress passed the Merchant Marine Act of 1936, which created the U.S. Maritime Commission whose mission was to modernize and build ships for the looming world war. Originally slated to build fifty ships a year for ten years as a part of the New Deal attack on a sagging economy, the Maritime Commission ended up building over 5,000 ships by the end of 1945. This paper examines the critical role of the civilian United States Merchant Marine in the struggle against the Japanese Empire
Poroacuatics Under Brinkman\u27s Model
Get PDFThrough perturbation analysis, a study of the role of Brinkman viscosity in the propagation of finite amplitude harmonic waves is carried out. Interplay between various parameters, namely, frequency, Reynolds number and beta are investigated. For systems with physically realizable Reynolds numbers, departure from the Darcy Jordan model (DJM) is noted for high frequency signals. Low and high frequency limiting cases are discussed, and the physical parameters defining the acoustic propagation are obtained.
Through numerical analyses, the roles of Brinkman viscosity, the Darcy coefficient, and the coefficient of nonlinearity on the evolution of finite amplitude harmonic waves is stud- ied. An investigation of acoustic blow-ups is conducted, showing that an increase in the magnitude of the nonlinear term gives rise to blow-ups, while an increase in the strength of the Darcy and/or Brinkman terms mitigate them. Finally, an analytical study via a regular perturbation expansion is given to support the numerical results.
In order to gain insight into the formation and evolution of nonlinear standing waves un- der the Brinkman model, a numerical analysis is conducted on the weakly nonlinear model based on Brinkman’s equation. We develop a finite difference scheme and conduct a param- eter study. An examination of the Brinkman, Darcy, and nonlinear terms is carried out in the context of their roles on shock formation. Finally, we compare our findings to those of previous results found in similar nonlinear equations in other fields.
So as to better understand the behavior of finite-amplitude harmonic waves under a Brinkman-based poroacoustic model, approximations and transformations are used to recast the Brinkman equation into the damped Burger’s equation. An examination is carried out for the two special solutions of the damped Burger’s equation: the approximate solution to the damped Burger’s equation and the boundary value problem given an initial sinusoidal pulse. The effects of the Darcy coefficient, Reynolds number, and nonlinear coefficient on these solutions are investigated
The Impact of Louisiana\u27s COMPASS Teacher Evaluation System on Principals in one School District: A Case Study
Get PDFAs teacher evaluation practices become increasingly high-stakes, principal observation has been made an important source of data in the evaluation process. Driven by the federal Race to the Top initiative, implementation of teacher evaluation systems has been rapid and questions remain about the preparedness of principals to successfully implement the new evaluation processes. The researcher conducted a qualitative case study that focuses on the implementation of the Louisiana Department of Education\u27s COMPASS teacher evaluation system and its impacts on principals in one school district. Interviews were conducted with six principals, a focus group was held with the four members of the district central office that supervise and support these principals, and two more focus group were held with selected teachers from the schools of each of the participating principals. Viewed through the lens of Transformational Leadership, data was collected, transcribed, analyzed, and organized into themes in order to present a practical and real-life perspective on how the COMPASS mandate has impacted principals. Findings indicate that principals perceive that COMPASS was implemented too quickly and they have had to change several of their practices as a result. Additionally, principals believe their biggest success in implementing COMPASS was supporting teachers, while they believe their biggest challenge in implementing COMPASS to be setting student learning targets that are both reasonable and challenging, and aligning school practices with those set forth in the COMPASS Rubric. Implications of this research include practical knowledge for current principals and administrators, and a ground-level view for policy makers regarding how mandates and change impact principals, as well as scholars seeking to understand the change process
Contemporary Arts Center: A Time of Transition
Get PDFThe following report documents my 480-hour internship from August 17th, 2015 to January 29th, 2016 in the Education and Public Programs Department at the Contemporary Arts Center (CAC). I worked closely with the Marketing and Visual Art Departments. I chose the organization to experience an environment that commits itself to presenting high quality performing and visual arts. This paper assesses the CAC’s history, present day status, and future outlook. It also offers suggestions on how certain aspects can be improved in order to extend the organization’s longevity. Over the course of five months I observed strengths, weaknesses, opportunities and threats to the organization. Additionally, using knowledge gained from my Arts Administration classes and personal observations, this paper offers predictions as to the organization’s future