Flow Characterization of the UTSA Hypersonic Ludwieg Tube

Abstract

The characterization of a hypersonic impulse facility is performed using a variety of methods including Pitot probe scans, particle image velocimetry, and schlieren imaging to verify properties such as the velocity, Mach number, wall boundary layer thickness, and freestream turbulence intensity levels. The experimental results are compared to the numerical simulations of the facility performed with Ansys Fluent to compare the design and operational conditions. The presentation of results in this manuscript is prefaced by a description of the facility and its capabilities. The UTSA Ludwieg tube facility can produce a hypersonic freestream flow with a Mach number of 7.2 ± 0.2 and unit Reynolds numbers of up to 200 × 106 m−1. The Pitot probe profiles of the 203-mm-square test section indicate a 152 ± 10 mm square freestream core with turbulence intensity values ranging from 1% to 2%. Schlieren imaging of the oblique shockwaves on a 15° wedge model provided an alternate means of verifying the Mach number. Particle image velocimetry and previous molecular tagging velocimetry results showed a good agreement with the Pitot probe data and numerical simulations in the key parameters including freestream velocity, wall boundary layer velocity profiles, and wall boundary layer thickness.

Thermal Evaluation of the Initial Concept 3.X Vehicle at Mach 7

“…The freestream velocity was found to be 885 m/s [21]. A detailed description of this facility's design, construction, and capabilities is presented by Bashor et al [28] and Hoffman et al [29][30][31]. A summary of the test conditions for the experimental campaign is provided in Table 1.…”

“…[32]. The data obtained were processed to mitigate noise, similarly to the PSP experimental campaign described in Dhanagopal et al [31].…”

Fast-Responding Pressure-Sensitive Paint Measurements of the IC3X at Mach 7.2

“…The experimental campaign was conducted at the hypersonic Ludwieg Tube Wind Tunnel facility located at UTSA. This facility can generate a freestream Mach number of 7.2 ± 0.2 [28,29]. Figure 1 illustrates a CAD rendering of the UTSA Mach 7 wind tunnel, highlighting its main components.…”