Keywords

Hypersonic Aerospace Vehicles, Thermal Management, Active Impingement Cooling, Supercritical Carbon Dioxide (sCO2), Conjugate Simulations, Power generation, Two Temperatures model, Leading edges

Abstract

This study addresses the critical need for effective thermal management in hypersonic vehicles facing intense heat at their leading edge due to high enthalpy flow. The objective is to propose an active impingement cooling system that ensures the structural stability and performance of these vehicles. This dissertation presents an in-depth exploration of the numerical simulations conducted on the hypersonic leading edge, focusing on a 3mm radius with active cooling utilizing supercritical carbon dioxide (sCO2) as the coolant. The research incorporates conjugate simulations that merge external hypersonic flow and sCO2 active cooling. Utilizing a thermodynamic non-equilibrium two-temperature model and various chemical models, including the 5-species Park's model and the 11-species Gupta's model, separate validations for the external hypersonic flow and internal sCO2 coolant flow were conducted. These validations facilitated combined simulations, underscoring the potential of maintaining metal temperatures within operational limits using sCO2 coolant. A comparative study of the 5- 5-species Park model and 11-species Gupta model demonstrated the former's effectiveness in predicting flow fields at Mach 7. Furthermore, this study shows the effect of varying the coolant tube-to-leading-edge distance (H/D), Thermal barrier coating thickness, and impingement angles, demonstrating improved heat transfer performance through these variations. A key aspect of this work is the exploration of converting hypersonic vehicle heat flux to power using the sCO2 cycle. The conceptual study, illustrated through the Mach 7 case, confirms the feasibility of harnessing power from aerodynamic heat flux, marking a significant progression in the field. This research contributes to the field by offering a detailed analysis of active impingement cooling for hypersonic leading edges, integrating real gas effects and multiple chemical models. The study adds novelty by investigating heat transfer enhancements through iv geometric variations and evaluating sCO2's potential as a coolant, addressing key facets of hypersonic vehicle thermal management.

Completion Date

2023

Semester

Fall

Committee Chair

Kapat, Jayanta

Degree

Doctor of Philosophy (Ph.D.)

College

College of Engineering and Computer Science

Department

Mechanical and Aerospace Engineering

Degree Program

Mechanical Engineering

Format

application/pdf

Identifier

DP0028085

URL

https://purls.library.ucf.edu/go/DP0028085

Language

English

Release Date

December 2023

Length of Campus-only Access

None

Access Status

Doctoral Dissertation (Open Access)

Campus Location

Orlando (Main) Campus

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