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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.
1

Nonlinear combustion instability in liquid propellant rocket engines

Powell, Eugene Alexander 12 1900 (has links)
No description available.
2

A theoretical study of nonlinear longitudinal combustion instability in liquid propellant rocket engines

Lores, Manuel Edward 05 1900 (has links)
No description available.
3

Technique for the optimization of the powerhead configuration and performance of liquid rocket engines

St. Germain, Brad David 08 1900 (has links)
No description available.
4

The conceptual design of a Mars nuclear landing and ascent vehicle utilizing indigenous propellant /

Zubrin, Robert M. January 1992 (has links)
Thesis (Ph. D.)--University of Washington, 1992. / Vita. Includes bibliographical references (leaves [144]-153).
5

Techniques to Assess Acoustic-Structure Interaction in Liquid Rocket Engines

Davis, R. Benjamin January 2008 (has links)
Thesis (Ph. D.)--Duke University, 2008. / Includes bibliographical references.
6

Aerospace design optimization using a real coded genetic algorithm

Dyer, John David, Hartfield, Roy J., January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 83-85).
7

Simulations of a sub-scale liquid rocket engine transient heat transfer in a real gas environment /

Masquelet, Matthieu M. January 2006 (has links)
Thesis (M. S.)--Aerospace Engineering, Georgia Institute of Technology, 2007. / Ruffin, Stephen, Committee Member ; Seitzman, Jerry, Committee Member ; Menon, Suresh, Committee Chair.
8

Investigation of injector system and gas generator propellant for aft-injected hybrid propulsion /

Pilon, Bryan January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 194-202). Also available in electronic format on the Internet.
9

Comparing Radiation Shielding Potential of Liquid Propellants to Water for Application in Space

Czaplewski, John 01 March 2021 (has links) (PDF)
The radiation environment in space is a threat that engineers and astronauts need to mitigate as exploration into the solar system expands. Passive shielding involves placing as much material between critical components and the radiation environment as possible. However, with mass and size budgets, it is important to select efficient materials to provide shielding. Currently, NASA and other space agencies plan on using water as a shield against radiation since it is already necessary for human missions. Water has been tested thoroughly and has been proven to be effective. Liquid propellants are needed for every mission and also share similar characteristics to water such as their density and hydrogenous composition. This thesis explores the shielding potentials of various liquid propellants as they compare to water for the purpose of providing an additional parameter when choosing propellants for any given mission. Testing propellants is done by first creating an experimental setup involving radioisotope sources Cs-137 and Co-60, a column of liquid with variable depths, and a Geiger-Mueller tube. Water and three other liquids: acetone, 70% isopropyl alcohol, and 12% hydrogen peroxide are physically tested and their linear attenuation coefficients are calculated. Then, the test setup is replicated in CERN’s Monte Carlo base radiation transport code, FLUKA. Although the calculated linear attenuation outputs from FLUKA are discrepant from experimental results by an average of 34%, they produce the same trends. FLUKA is used to expand upon experimental results by simulating a multitude of liquid propellants and comparing them all to water. FLUKA has the ability to simulate all propellants including hydrogen, oxygen, hydrazine, and dinitrogen tetroxide. Most of the tested propellants are found to have similar, to within 35%, gamma radiation linear attenuation coefficients as compared to water. The gamma radiation in this thesis’s experiment and simulations comes from Cs-137 and Co-60 radioisotope sources. For gamma radiation from the Co-60 source, liquid hydrogen provides 90% less attenuation than water and nitric acid and AF-M315E provide 35% and 38% more attenuation than water respectively. For gamma radiation emitted by Cs-137, liquid hydrogen, isopropyl alcohol, and methane have 90%, 35%, and 29% less attenuation than water respectively. Dinitrogen tetroxide, hydrogen peroxide, AF-M315E, and nitric acid have 34%, 41%, 46%, and 52% greater attenuation coefficients than water respectively. The liquids that are similar to water for the Cs-137 source have linear attenuation coefficients within 20% of water’s. Ultimately, most of the tested liquid propellants are shown to shield against radiation at a similar rate to water. Thus, an additional parameter for choosing liquid propellants on any given mission should be their radiation shielding capabilities.
10

Validated Prediction Of Pressurant Gas Requirements In Cryogenic Run Tanks At Subcritical And Supercritical Pressures

De Quay, Laurence 11 December 2009 (has links)
The development, testing, and use of liquid propellant and hybrid rocket propulsion systems for spacecraft and their launch vehicles routinely involves the use of cryogenic propellants. These propellants provide high energy densities that enable high propulsive efficiency and high engine thrust to vehicle weight ratios. However, use of cryogenic propellants also introduces technical problems not associated with other types of propellants. One of the major technical problems is the phenomenon of propellant tank pressurant and ullage gas collapse. This collapse is mainly caused by heat transfer from most of the ullage gas to tank walls and interfacing propellant, which are both at temperatures well below those of this gas. Pressurant gas is supplied into cryogenic propellant tanks in order to initially pressurize these tanks and then to maintain required pressures as propellant is expelled from these tanks. The cryogenic propellants expelled from the tanks feed rocket engine assemblies, subassemblies, and components at required interface pressures and mass flow rates. The net effect of pressurant and ullage gas collapse is increased total mass and mass flow rate requirements of pressurant gases. For flight vehicles this leads to significant and undesirable weight penalties. For rocket engine component and subassembly ground test facilities this results in high construction and operational cost impacts. Accurate predictions of pressurant gas mass transfer and flow rate requirements are essential to the proper design of systems used to supply these gases to cryogenic propellant tanks. While much work has been done in the past for predicting these gas requirements at low subcritical tank pressures, very little has been done at supercritical tank pressure conditions and there are selected cases where errors of analytical predictions are high. The objectives of this study are to develop a new generalized and improved computer program to determine pressurant gas requirements at both subcritical and supercritical tank pressure conditions, and then evaluate and validate the consistent accuracy of this program over a wide range of conditions by comparison of program results to empirical data.

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