축류압축기 회전익 후방의 허브부근에서 후류의 특성

Abstract

축규압축기 회전익의 후방유동장을 45? 단일경사열선을 이용하여 측정하였고 특히 회전익 후방유동중 허브부근의 후류특성을 절현비에 따라 제시하였다.

유종장은 회전익으로부터 회전에너지를 받기 때문에 회전익이 회전하는 방향으로 회전하며 스팬(span)의 중간위치에서 후류의 중심들은 이현방향과 거의 일치한다. 또한 허브부근에서 후류의 중심들은 절현비가 큰 경우 회전하는 방향으로 편향되어 나타나고 있으나 잘현비가 작은류의 중심들은 절현비가 작은 경우에는 회전익의 회전방향과 반대방향으로 편향되어 나타나는데 이는 후류의 경계와 결합된와류 때문인 것으로 보여진다. 이러한 사실은 절현비가 큰 경우 말발굽와류, 코너와규 그리고 후류가 뚜렷이 구별되어 나타나고 있으나 절현비가 작은 경우 이러한 와류들과 후류는 서로 결합되어 새로운 와류를 형성하는 것으로부터 알 수 있다. 이러한 효과는 스팬의 ?? 이 상에서 사라진다.

Measurement was made of the flow behind the rotor of a compressor by using a 45-degree-slanted hot wire. The characteristics of the wakd near the hub flow behind the rotor are investigated by the change of the pitch-chord ratio.

The flow field rotors in rotational direction bacause of the field accepting the energy from a roter. The trace fo the wake center in the mid-span region almost lies on an extended line in the chord-wise direction, irrespective of pitch-chord rations. In the hub region, the wake center is shifted toward the rotational direction in the case of large pitch-chord ratio but it is shifted toward the anti-rotational firection in the case of small one because of the vortex mising with the boundaries of the wake. Also Near the hub region the house shoe vortex, the corner vortex and the wake appear clearly in the large pitch-chord ratio, but in the small pitch chord ratio these vortices and the wake are combined and form a new vortex. This effect disappers in the upper region from the ??.

Measurement was made of the flow behind the rotor of a compressor by using a 45-degree-slanted hot wire. The characteristics of the wakd near the hub flow behind the rotor are investigated by the change of the pitch-chord ratio.

The flow field rotors in rotational direction bacause of the field accepting the energy from a roter. The trace fo the wake center in the mid-span region almost lies on an extended line in the chord-wise direction, irrespective of pitch-chord rations. In the hub region, the wake center is shifted toward the rotational direction in the case of large pitch-chord ratio but it is shifted toward the anti-rotational firection in the case of small one because of the vortex mising with the boundaries of the wake. Also Near the hub region the house shoe vortex, the corner vortex and the wake appear clearly in the large pitch-chord ratio, but in the small pitch chord ratio these vortices and the wake are combined and form a new vortex. This effect disappers in the upper region from the ??.