Design and Testing of an Intrusive Arm for Supersonic Flow Sampling

Intrusive probes are critical tools in supersonic wind tunnel testing, enabling direct measurement of flow properties such as pressure and heat flux. To support these measurements, a single-axis intrusive arm was designed and implemented in the Missouri S&T Supersonic Wind Tunnel. The system is designed to maintains precise probe positioning, while withstanding the aerodynamic loads, and preserving a dynamic seal between the test section and ambient environment. Its modular design accommodates a range of probe types for various research applications. This paper presents the design methodology, including structural, mechanical, and aerodynamic considerations, and details the integration process. System performance was validated through a series of tests using a total pressure probe, which confirmed stable Mach 3 flow across the test section and demonstrated the arm's ability to deliver accurate, repeatable measurements. The addition of the intrusive arm significantly enhances the facility’s diagnostic capabilities, providing a robust platform for advanced supersonic flow studies.