The latest addition to the gas dynamics was in 2018 with the installation of the quad-sonic wind tunnel (QSWT). The QSWT is a blow down tunnel comprising four interchangeable converging-diverging nozzles that produce Mach numbers of 2, 3, 4 and 5 through a 4-inch x 6-inch (H x W) test section. A rendering of the QSWT concept is shown in Figure 1a alongside a digital image after fabrication and installation.
The floor of the QSWT has several removable inserts that provide access to the test section and for mounting different test hardware. Figure 2a shows a generic conical shaped test article during testing in QSWT. Run times are on the order of 10s of seconds, depending on the nozzle and starting tank pressure. Figure 2b illustrates a run time of 35 seconds of the Mach 5 nozzle using a starting tank pressure of 1000 psi. Given the charge rate of the compressor, several extended run times of the QSWT can be performed during a typical workday. Several static wall pressure sensing taps are placed throughout the QSWT and are monitored using a 16 channel gas pressure scanner during each run.