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Full-Text Articles in Engineering
Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir
Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir
Theses and Dissertations
Scramjet engines are key for sustained hypersonic flights. Analytic models play a critical role in the preliminary design of a scramjet engine configuration. The objective of this research is to develop and validate a quasi-1D model for the scramjet engine encompassing inlet, isolator and combustor, to evaluate the impact of flight conditions and design parameters on the engine functionality. The model is developed assuming isentropic flow in the inlet with a single turn; modified Fanno-flow equations in the isolator that account for the area change of the core flow; and the combustor is modeled using Heiser-Pratt equations accounting for the …
Development And Implementation Of A Novel Resonantly Ionized Photoemission Thermometry Technique For One-Dimensional Measurements, Walker B. Mccord
Development And Implementation Of A Novel Resonantly Ionized Photoemission Thermometry Technique For One-Dimensional Measurements, Walker B. Mccord
Doctoral Dissertations
In this work, Resonantly Ionized Photoemission Thermometry (RIPT) is established and validated as a novel, non-intrusive, non-seeded, One-Dimensional (1D) line thermometry technique. The RIPT technique resonantly ionizes a target molecule via REMPI (Resonant Enhanced Multi-Photon Ionization) of selectively chosen rotational peaks within a resonant absorption band. Thus, efficiently ionizing and subsequently exciting local nitrogen molecules either by direct or indirect schemes. The excited nitrogen deexcites through photoemissions of the first negative band of N2+[molecular nitrogen], specifically near 390, 425, and 430nm [nanometers], that is then acquired as a 1D line signal. The signal strength at all transitions …
Upscaling And Development Of Linear Array Focused Laser Differential Interferometry For Simultaneous 1d Velocimetry And Spectral Profiling In High-Speed Flows, Kirk Davenport
Masters Theses
In this research a new configuration of linear array-focused laser differential interferometry (LA-FLDI) is described. This measurement expands on previous implementations of LA-FLDI through the use of an additional Wollaston prism. This additional prism expands the typical single LA-FLDI column into two columns of FLDI point pairs. The additional column of probed locations allows for increased spatial sampling of frequency spectra as well as the addition of simultaneous wall normal velocimetry measurements. The new configuration is used to measure the velocity profile and frequency content across a Mach 2 turbulent boundary layer at six wall normal locations simultaneously. Features of …
Hypersonic Conceptual Design Tool Comparison, James G. Wnek
Hypersonic Conceptual Design Tool Comparison, James G. Wnek
Browse all Theses and Dissertations
The many iterations needed to explore a design space in the conceptual design process preclude the use of time-consuming RANS CFD for all but a few flight conditions. This research focuses on identifying the level of fidelity needed to adequately predict the aerothermodynamic characteristics of hypersonic vehicles. Three tools with differing levels of fidelity – CBAERO, Cart3D, and Kestrel – were used to analyze the Generic Hypersonic Vehicle (GHV) at the design condition of Mach 5.85 and an off-design condition of Mach 4.5. The results are representative of the different design tools but are not definitive due to the mesh …
Design Of A Surrogate Hypersonic Inlet For The Hifire-6 Configuration, Joseph W. Mileski
Design Of A Surrogate Hypersonic Inlet For The Hifire-6 Configuration, Joseph W. Mileski
Browse all Theses and Dissertations
Shock wave-boundary layer interactions can significantly impact the operability of high-speed inlets by inducing flow separation. This flow separation is difficult to visualize in three-dimensional, inward-turning inlets because of the curved surfaces that form their internal flow paths. To remedy this challenge, a surrogate test article was created. Using the results from a previously completed Computational Fluid Dynamic (CFD) analysis of the HIFiRE-6, a surrogate inlet with a rectangular isolator section was streamline-traced, allowing for the use of schlieren imagery to capture the separation bubble. This thesis discusses the process of developing the test article. Experimental results from a planned …