Experimental Study of High-Altitude Simulation using Small-Scale Supersonic Diffuser

Lee, Ji-Hyung; Oh, Jong-Yun; Byun, Jong-Ryul

Journal of the Korea Institute of Military Science and Technology 2004;7(4):138-145.

Ji-Hyung Lee, Jong-Yun Oh, Jong-Ryul Byun

Agency for Defense Development

소형 초음속 디퓨저를 이용한 고고도환경 모사에 대한 시험적 연구

이지형, 오종윤, 변종렬

국방과학연구소 기술연구본부

Abstract

Experimental study was conducted on cylindrical supersonic diffuser in order to investigate the effects of the ratios of diffuser area to nozzle throat area (Ad/At), diffuser area to nozzle exit area (Ad/Ae), nozzle exit area to its throat area (Ae/At), and diffuser length to its diameter (L/D), the free volume of vacuum chamber, and the relative distance between nozzle exit and diffuser inlet on the diffuser performance. The study showed that the minimum diffuser starting pressure (Po/Pa)st increased monotonically with increase in (Ad/At) as predicted by the normal shock and momentum theory models and the volume of vacuum chamber affected vacuum pressure level during diffuser operation at lower value of (Ad/Ae). The results of this investigation will be utilized in the design of real-scale high-altitude simulation test facility.