Matching Items (3)
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- All Subjects: Aerospace Engineering
- Genre: Masters Thesis
Description
This thesis seeks to further explore off-design point operation of gas turbines and to examine the capabilities of GasTurb 12 as a tool for off-design analysis. It is a continuation of previous thesis work which initially explored the capabilities of GasTurb 12. The research is conducted in order to: 1) validate GasTurb 12 and, 2) predict off-design performance of the Garrett GTCP85-98D located at the Arizona State University Tempe campus. GasTurb 12 is validated as an off-design point tool by using the program to predict performance of an LM2500+ marine gas turbine. Haglind and Elmegaard (2009) published a paper detailing a second off-design point method and it includes the manufacturer's off-design point data for the LM2500+. GasTurb 12 is used to predict off-design point performance of the LM2500+ and compared to the manufacturer's data. The GasTurb 12 predictions show good correlation. Garrett has published specification data for the GTCP85-98D. This specification data is analyzed to determine the design point and to comment on off-design trends. Arizona State University GTCP85-98D off-design experimental data is evaluated. Trends presented in the data are commented on and explained. The trends match the expected behavior demonstrated in the specification data for the same gas turbine system. It was originally intended that a model of the GTCP85-98D be constructed in GasTurb 12 and used to predict off-design performance. The prediction would be compared to collected experimental data. This is not possible because the free version of GasTurb 12 used in this research does not have a module to model a single spool turboshaft. This module needs to be purchased for this analysis.
ContributorsMartinjako, Jeremy (Author) / Trimble, Steve (Thesis advisor) / Dahm, Werner (Committee member) / Middleton, James (Committee member) / Arizona State University (Publisher)
Created2014
Description
In recent years, a new type of ionic salt based solid propellant, considered inert until the application of an electric current induces an electro-chemical reaction, has been under investigation due to its broad range of possible uses. However, while many electric propellant formulations and applications have been explored over the years, a fundamental understanding of the operational mechanisms of this propellant is necessary in order to move forward with development and implementation of this technology. It has been suggested that the metallic additive included in the formulation studied during this investigation may be playing an additional, currently unknown role in the operation and performance of the propellant. This study was designed to examine variations of an electric propellant formulation with the purpose of investigating propellant bulk volume electrical resistivity in order to attempt to determine information regarding the fundamental science behind the operation of this material. Within a set of fractional factorial experiments, variations of the propellant material made with tungsten, copper, carbon black, and no additive were manufactured using three different particle size ranges and three different volume percentage particle loadings. Each of these formulations (a total of 21 samples and 189 specimens) were tested for quantitative electrical resistivity values at three different pulse generator input voltage values. The data gathered from these experiments suggests that this electric propellant formulation’s resistivity value does change based upon the included additive. The resulting data has also revealed a parabolic response behavior noticeable in the 2D and 3D additive loading percentage versus additive particle size visualizations, the lowest point of which, occurring at an approximately 2.3% additive loading percentage value, could be indicative of the effects of the percolation phenomena on this material. Finally, the investigation results have been loosely correlated to power consumption testing results from previous work that may indicate that it is possible to relate propellant electrical resistivity and operating requirements. Throughout this study, however, it is obvious based on the data gathered that more information is required to be certain of these conclusions and in order to fully understand how this technology can be controlled for future use.
ContributorsBrunacini, Lauren (Author) / Middleton, James (Thesis advisor) / Dai, Lenore (Committee member) / Langhenry, Mark T (Committee member) / Arizona State University (Publisher)
Created2019
Description
The Doghouse Plot visually represents an aircraft’s performance during combined turn-climb maneuvers. The Doghouse Plot completely describes the turn-climb capability of an aircraft; a single plot demonstrates the relationship between climb performance, turn rate, turn radius, stall margin, and bank angle. Using NASA legacy codes, Empirical Drag Estimation Technique (EDET) and Numerical Propulsion System Simulation (NPSS), it is possible to reverse engineer sufficient basis data for commercial and military aircraft to construct Doghouse Plots. Engineers and operators can then use these to assess their aircraft’s full performance envelope. The insight gained from these plots can broaden the understanding of an aircraft’s performance and, in turn, broaden the operational scope of some aircraft that would otherwise be limited by the simplifications found in their Airplane Flight Manuals (AFM). More importantly, these plots can build on the current standards of obstacle avoidance and expose risks in operation.
ContributorsWilson, John Robert (Author) / Takahashi, Timothy T (Thesis advisor) / Middleton, James (Committee member) / White, Daniel (Committee member) / Arizona State University (Publisher)
Created2017