High-Speed Pressure-Sensitive Paint Measurements of a Hypersonic Vehicle

Date
2022
Authors
Elizondo, Valeria Delgado
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract

Surface pressure measurements are essential to evaluate aerodynamic loads on a vehicle during flight. Pressure-sensitive paint (PSP) is an optical experimental technique that is widely used in the aerodynamics field due to its capability to acquire pressure measurements with high spatial and temporal resolution . A fast-responding pressure sensitive paint (fast-PSP) was applied to a 5.7% scale, 3D printed model of the AFRL Initial Concept 3.X (IC3X) hypersonic vehicle at the UTSA Mach 7 Ludwieg Tube Wind Tunnel. A ruthenium-based Polymer/ceramic PSP (PC-PSP) was selected for this hypersonic application. Images of the model under steady conditions at M = 7.2 ± 0.2 flow were collected with a high-speed camera at 20k fps. A static calibration was performed to relate the luminescent emission of the paint to pressure over the range of 82.7 kPa to 0.386 kPa. An average surface pressure distribution of the model was obtained at both 0 and 2.5 AoA. Proper orthogonal decomposition (POD) analysis was done to characterize the structures that make up the pressure fields of this hypersonic vehicle. In addition, Schlieren images were collected to visualize flow structures and conical shock analysis was conducted to compare theoretical and experimental measurements. Other results such as power spectral density (PSD) and PSP derived pressures at various locations within the surface of the vehicle are presented. Details on the paint application methods and image processing techniques are provided. This work presents preliminary quantitative pressure measurements that will contribute as training data to aerothermodynamic machine learning models that are being developed as part of NASA's ULI Full Airframe Sensing Technology (FAST) project.

Description
This item is available only to currently enrolled UTSA students, faculty or staff.
Keywords
Fast PSP, Hypersonic Research, Hypersonic Wind Tunnel Testing, PC PSP, Porous PSP, Pressure Sensitive Paint
Citation
Department
Mechanical Engineering