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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.
31

Flow field investigation in pulse 1 motor of a two-pulse solid rocket motor

Qian, Xin 12 March 2009 (has links)
A water analogy technique was used in this investigation of the flow field in the pulse I motor of a two-pulse solid rocket motor. A full scale model of clear acrylic material was constructed to allow direct visual access of the flow field. The experiment, which was conducted with one of the VPI water analogy rigs, simulated the flow in the spent pulse I motor chamber after the pulse Il motor would have been ignited. The relations between the pattern and angle of the throughflow holes on the bulkhead--which separates the two motor chambers--and the downstream flow pattern in the pulse I chamber were assessed by changing the bulkhead model configuration for each test. Video records of the flow pattern were obtained through flow visualization tests, which used either fluorescein dye or air bubbles as the tracer. Also, hot water tests with thermocouple measurements were conducted as a means of investigating the rate of mixing of the propellent from the pulse Il motor with the gases in the pulse I motor chamber, as well as the migration of the pulse Il propellent along the wall of the pulse I motor casing. The test data show a clear relation between the hole arrangement on the bulkhead and the ensuing downstream flow pattern, as well as the rate of mixing along the wall of the pulse I motor casing. Consequently, the results provide directions for improving the performance of heat transfer insulation material on the wall of the pulse I motor through a prudent choice of the hole arrangement on the bulkhead. / Master of Science
32

Quasi-optimal steady state and transient maneuvers with and without thrust vectoring

Dwyer, Michael E. 29 September 2009 (has links)
Steady state and transient maneuver problems for a high performance fighter aircraft with and without thrust vectoring are investigated. The steady state aspect of these studies determines control combinations with and without thrust vectoring which optimize selected level-flight point performance criteria including minimum speed, maximum instantaneous range, and maximum sustained turn rate. The transient maneuvers are initiated from straight and level flight and include a longitudinal pitch-up to a desired fuselage pointing angle and a lateral-directional transition (wind-up) to a desired steady level turn rate. For the transient maneuvers, a full six-degree-of-freedom model of the aircraft is used with three conventional aerodynamic controls, throttle control and pitch and yaw thrust vectoring control. Each of the control time histories are parameterized so as to include both the rate and range limits of the controls. A nonlinear programming algorithm is used to determine the control parameter values which yield the minimum time to execute the prescribed maneuvers. Results indicate that thrust vectoring does not significantly change the steady state behavior in the scenarios investigated. However, flight times for the transient maneuvers are found to be reduced by up to 28%. The greatest effect of thrust vectoring occurs at low Mach number. / Master of Science
33

Investigation of the flow turning loss in unstable solid propellant rocket motors

Matta, Lawrence Mark 12 1900 (has links)
No description available.
34

Thermal and fracture behaviour of rocket motor materials / by Kim Martin Ide.

Ide, Kym Martin January 1997 (has links)
Bibliography: leaves 190-196. / vi, 197 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis analyses the way in which ageing, temperature and strain-rate affect the thermal and fracture properties of the polymeric components in the PICTOR rocket motor. The change in the thermal expansion behaviour of the propellant, inhibitor, epoxy and insulation is investigated. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 1997?
35

Design and analysis of rocket nozzle contours for launching pico-satellites /

Denton, Brandon Lee. January 2008 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (leaves 110-111).
36

Experimental and numerical study of a hydrogen peroxide / hydroxyl terminated polybutadiene hybrid rocket /

Farbar, Erin January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 163-172). Also available in electronic format on the Internet.
37

Propellant tank pressurization modeling for a hybrid rocket /

Fernandez, Margaret Mary. January 2009 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (leaves 70-73).
38

An efficient technique for structural reliability with applications /

Janajreh, Ibrahim Mustafa, January 1992 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 181-186). Also available via the Internet.
39

Fuel optimal low thrust trajectories for an asteroid sample return mission /

Rust, Jack W. January 2005 (has links) (PDF)
Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, March 2005. / Thesis Advisor(s): I. Michael Ross. Includes bibliographical references (p. 57-58). Also available online.
40

Internal flow investigation of an aft finocyl grain configuration in a solid rocket motor

Hetreed, Christopher F. 29 November 2012 (has links)
Cold-flow tests were conducted in mediums of air and water to investigate the internal flow field about the nozzle region of a proposed solid rocket motor (SRM) configuration that would potentially replace the current external boosters on NASA's Space Shuttle. One-eighth-scale clear acrylic models of the proposed submerged aft-dome and aft finned grain elements were constructed to simulate the aft segment of the SRM at ignition and 35 seconds into the firing sequence. Pressure, velocity, and turbulence profiles were obtained during cold air testing, while air bubbles and dye were used for flow visualization during water tunnel testing. The flow visualization experiments indicated the presence of strong inlet vortices, alternating vortex shedding from both grain models' fins, circumferential flow in the aft-dome and around the nozzle, and recirculatory flow in the aft-dome and near an upstream portion of the 35-second grain model. Data acquired during cold air testing showed a turbulent low-velocity flow field in the aft-dome for both grain models. With respect to pressure and mean velocity virtually the entire nozzle/aft-dome region exhibited a minimal sensitivity to nozzle vectoring. / Master of Science

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