Experimental Studies of Radiation and Plasma Effects behind the Incident Shock in LENS XX, and the Unsteady Flow Characteristics associated with 'Free Flight' Shroud and Stage Separation and Mode Switching in LENS II.

摘要

The LENS XX facility was developed principally to generate clean hypervelocity flows in which we can perform experiments to evaluate nonequilibrium and real gas effects in the shock layers surrounding vehicles flown at velocities from 3 km/s to 14 km/s, and to study shock layer radiation and the properties of plasmas surrounding hypersonic vehicles as they enter the earth s atmosphere and those of other planets. Currently our research is directed toward examining the radiation behind a shock front traveling at 10 km/s for direct comparison with measurements made in East Facility at NASA Ames and developing a test program to obtain ground test measurements to directly compare with measurements made earlier in flight in the FIRE-II and RAM-C programs. Spectrographic measurements of the radiation behind a shock wave traveling at 10 km/s are being conducted in the expansion tube section of the LENS XX tunnel while those to replicate flight data are being made in the test section of the LENS XX facility as illustrated in Figure 1(a) and (b) respectively.