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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Particle image velocimetry in an advanced, serpentine jet engine inlet duct

Tichenor, Nathan Ryan 15 May 2009 (has links)
The overarching objective of this research project was to gain improved basic understanding of the fluid mechanisms governing the development of secondary flow structures in complex, three-dimensional inlet ducts. To accomplish this objective, particle image velocimetry measurements were employed to document the mean and turbulent flow properties within the complex flow regions. Complimentary, surface oil flow visualizations and static pressures were obtained to aid in the interpretation of the PIV data. Using these diagnostic techniques, the formation of a pair of counter-rotating vortices was revealed. Two-dimensional PIV measurements were conducted along 20 planes near the two bends of the duct model. All data was collected with an incoming freestream of 40 m/s. Over 2000 image pairs were collected for each measurement location, which were then processed and averaged to generate mean velocity, variance intensity, and velocity gradient statistics. The data was analyzed and it was determined that the experimental PIV data corresponded well with the qualitative flow visualization. This research will contribute to the particle image velocimetry database and subsequent analyses, which will provide additional insight into the flow structure and provide a new database for numerical model validation.
12

Particle image velocimetry applications in complex flow systems

Ertürk Düzgün, Nihal 04 June 2012 (has links)
El objetivo principal de esta tesis es la mejora y la aplicación de la técnica PIV para analizar diferentes flujos de fluidos complejos en los sistemas que contienen partes sólidos móviles o estacionarias. Las partículas de alginato con/sin compuesto de fluoresceína incrustada se han desarrollado como una serie de elementos alternativos de siembra de nuevas aplicaciones de flujo para el PIV. Se ha encontrado que las micro-partículas de alginato tienen muchas ventajas sobre los tradicionales utilizados en sistemas de PIV. Un estudio amplio sobre el análisis del flujo en tres dimensiones de la bomba de engranajes externa se ha hecho por la técnica tiempo-resuelva PIV para investigar la dinámica y las estadísticas de flujo turbulento. Vorticidad y zonas turbulentas de alta energía cinética se han identificado dentro de la bomba de engranajes externa. La técnica PIV se ha aplicado de manera eficiente para analizar un intercambiador de calor de motor de flujo de bypass en un túnel del viento de bajo velocidad. Las partículas de alginato que contienen fluoresceína se han utilizado eficientemente en los experimentos que conducen a mejorar la calidad de la imagen PIV y analizar las estructuras de pequeña escala de los flujos. / The main objective of the thesis is the improvement and application of the PIV technique to analyse different complex fluid flows in systems that contain solid moving or stationary parts. The alginate particles with/without fluorescein compound imbedded have been developed as a new alternative flow seeding elements for PIV applications. It has been found that the alginate micro particles have many advantages over traditional ones used in PIV systems. A comprehensive study on the three-dimensional flow analysis of the external gear pump has been done by time-resolved PIV technique to investigate its turbulent flow dynamics and statistics. Vorticity and high turbulent kinetic energy areas have been identified inside the external gear pump. The PIV technique has been efficiently applied to analyse an engine bypass flow heat exchanger in a low speed wind tunnel. The alginate particles containing fluorescein have been efficiently used in the experiments that lead to improve the PIV image quality and analyse the small-scale structures of the flows.
13

Particle image velocimetry in an advanced, serpentine jet engine inlet duct

Tichenor, Nathan Ryan 15 May 2009 (has links)
The overarching objective of this research project was to gain improved basic understanding of the fluid mechanisms governing the development of secondary flow structures in complex, three-dimensional inlet ducts. To accomplish this objective, particle image velocimetry measurements were employed to document the mean and turbulent flow properties within the complex flow regions. Complimentary, surface oil flow visualizations and static pressures were obtained to aid in the interpretation of the PIV data. Using these diagnostic techniques, the formation of a pair of counter-rotating vortices was revealed. Two-dimensional PIV measurements were conducted along 20 planes near the two bends of the duct model. All data was collected with an incoming freestream of 40 m/s. Over 2000 image pairs were collected for each measurement location, which were then processed and averaged to generate mean velocity, variance intensity, and velocity gradient statistics. The data was analyzed and it was determined that the experimental PIV data corresponded well with the qualitative flow visualization. This research will contribute to the particle image velocimetry database and subsequent analyses, which will provide additional insight into the flow structure and provide a new database for numerical model validation.
14

Development of a time resolved scanning particle image velocimetry system for measurement of the small scales of turbulent flows

Torregrosa, Maria del Mar, January 2009 (has links)
Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Mechanical and Aerospace Engineering." Includes bibliographical references (p. 113-114).
15

Free-surface film flow of a suspension and a related concentration instability

Timberlake, Brian D. January 2004 (has links) (PDF)
Thesis (Ph. D.)--Chemical Engineering, Georgia Institute of Technology, 2004. / Ludovice, Peter, Committee Chair; Lee, Jay, Committee Member; Meredith, Carson, Committee Member; Morris, Jeff, Committee Member; Neitzel, Paul, Committee Member. Vita. Includes bibliographical references (leaves 120-123).
16

Particle image velocimetry study of shock-induced turbulent boundary layer separation

Hou, Yongxi, Clemens, Noel T., January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: Noel T. Clemens Vita. Includes bibliographical references. Also available from UMI.
17

A study of thermal counterflow in HE II using particle image velocimetry (PIV) technique

Zhang, Tao. Van Sciver, Steven W. January 2004 (has links)
Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Steven W. Van Sciver, Florida State University, College of Engineering, Department of Mechanical Engineering. Title and description from dissertation home page (viewed June 16, 2004). Includes bibliographical references.
18

Particle image velocimetry study of shock-induced turbulent boundary layer separation

Hou, Yongxi 28 August 2008 (has links)
Not available / text
19

Digital PIV techniques for studies of circular cylinder under oscillating flow

湯健東, Thung, Kin-tung, Dick. January 2000 (has links)
published_or_final_version / Civil Engineering / Master / Master of Philosophy
20

Advanced technology applied to PIV measurement

Pan, Xiao Bo January 1996 (has links)
No description available.

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