가시화 기법을 사용한 자유낙하하는 반구모델의 자세각 및 항력계수 측정

Abstract

In this work, the effect of attitude angle variation on drag coefficients of hemisphere in a Mach 6 flow has been investigated. Experiments were conducted in a shock tunnel and a free-falling technique was used to minimize flow disturbance by a sting. For attitude and drag coefficient measurements of a free-falling hemisphere, a free-falling technique based on a releasing mechanism with a stair-typed module and an electromagnet was developed. A shadowgraph technique was used for flow visualization using a high-speed camera.