Hypersonic Ground Tests In Support of the Boundary Layer Transition (BOLT) Flight Experiment

Shock-induced heating and transition to turbulence in a hypersonic boundary layer

“…For this reason, the simulations employ an undisturbed laminar inflow. Figure 33 shows good agreement between the Stanton number distribution obtained from the simulations using charLES and from the experiments reported in Berridge et al (2018) and Thome et al (2019). The streaky structures in the Stanton number distribution, caused by cross-flow instabilities, are predicted by the simulations, particularly near the centreline, where the boundary layer is lifted by the stationary streamwise vortices with mushroom-like structures.…”

“…In the vicinity of the nose, the ratio of the nose radius to the minimum grid spacing in the wall tangent direction is 32, indicating sufficient resolution to resolve the locally large curvature of the vehicle edges. The simulations are compared with experiments performed in the Boeing-AFOSR Mach-6 Quiet Tunnel (BAM6QT) at Purdue University, which is known to have a very low level of free-stream disturbances (Schneider 2008;Berridge et al 2018). For this reason, the simulations employ an undisturbed laminar inflow.…”

“…The streaky structures in the Stanton number distribution, caused by cross-flow instabilities, are predicted by the simulations, particularly near the centreline, where the boundary layer is lifted by the stationary streamwise vortices with mushroom-like structures. Further quantitative comparisons are provided in figure 34 (Berridge et al 2018;Thome et al 2019). In the notation, L r represents the streamwise length of the vehicle.…”

Preflight Ground Test Analyses of the Boundary Layer Transition (BOLT) Flight Geometry

“…The BOLT flight test geometry was designed by JHUAPL [19,28]. Experimental testing of two 33% scale models will be discussed in this paper.…”

“…Johns Hopkins University Applied Physics Laboratory designed and fabricated a 33% scale model that was tested at TAMU, Purdue University, and NASA Langley Research Center. The scale was chosen based on testing requirements of the BOLT geometry within the Purdue Boeing/AFOSR M6QT (BAM6QT) [28]. Dimensions for the 33% scale model are shown in Fig.…”