Flow Characterization at Heated Air Supersonic Facility SBR-50

The supersonic wind tunnel facility SBR-50 at the University of Notre Dame was built in 2015 for experimental research related to shock wave (SW) interactions with obstacles and boundary layers (BL) as well as supersonic combustion and a plasma-based flow control. Currently, the facility provides the following range of flow parameters with a test section area at the nozzle exit of 76.2 x 76.2 mm: Mach number M=2 and 4, total pressure p(0)= 1-4 bar, stagnation temperature T-0= 300-775 K, and typical duration of the steady-state flow t = 0.5-2 s. One distinct feature of the facility is the Ohmic gas heater installed in a long plenum section. Objective of this study is to characterize flow in the SBR-50 facility, specifically the dynamics of the gas temperature. Two measuring methods were applied for collection of a detailed dataset: thermocouple measurements and schlieren-based thermal mark (laser spark) velocimetry. The experimental data are compared with 3D Navier-Stokes modelling of the gas parameters over the entire flowpath. Particularly, this study proves that the original facility schematics (the concept of a virtual piston in the plenum) allow for a longer operation with a constant stagnation temperature compared to a constant plenum volume with adiabatic cooling of the stored gas.

Automated summary

This study introduces the supersonic wind tunnel facility SBR-50 at the University of Notre Dame, which is used for experimental research on shock wave interactions, supersonic combustion, and plasma-based flow control. The objective of the study is to characterize the flow dynamics and gas temperature in the facility. Two measuring methods, thermocouple measurements and schlieren-based thermal mark velocimetry, were used to collect experimental data, which were compared with 3D Navier-Stokes modeling. The study demonstrates that the original facility schematics allow for longer operation with a constant stagnation temperature compared to adiabatic cooling.