Star-Body Waveriders with Multiple Design Mach Numbers

A new type of star-body waverider is presented that has multiple design Mach numbers. A limitation of typical waverider configurations is that they have a single design Mach number, where the shock wave is attached to all of its leading edges. At this design Mach number, there is no flow spillage and the static pressure on the compression surfaces is maximized. The center wedge sections of the new star bodies have different flow deflection angles corresponding to different design Mach numbers, thereby generating lift and side force that can be used for increased range and maneuver capability. A baseline Mach 6, conventional star body, an equivalent volume cone, and three multiple-design-Mach-number star bodies are analyzed using three-dimensional, full Navier-Stokes computational fluid dynamics for Mach numbers of 4, 5, 6, 7, and 8 and an altitude of 100,000 ft. As expected, the conventional, single-design-Mach-number star body has higher skin-friction drag, lower wave drag, and lower total drag than the equivalent volume cone. Because the volumes of the multiple-design-Mach-number star bodies are greater than that of the cone, they have higher total drag than the cone, but the wave drag and drag coefficient are lower than the equivalent cone for some of the new configurations at higher Mach numbers. Before performing the analysis, it was assumed that the star body sectors at an on-design flow condition would have the greatest pressure levels. However, the computational fluid dynamics analysis showed that the star-body sectors with the maximum flow deflection (center wedge) angle produced the highest pressures, even at off design How conditions, where three-dimensional effects and pressure loss due to detached shocks and flow spillage are present. The asymmetric, two-, and triple-design-Mach-number star bodies produced lift that can be used for downrange and cross-range capability.