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Effects of Incidence on Aerodynamic Losses in the Tip-Leakage Flow Region of a High-Turning Turbine Rotor Blade

입사각이 터빈 동익 팁누설유동 영역에서의 압력손실에 미치는 영향

  • 채병주 (금오공과대학교 기계공학부 대학원) ;
  • 이상우 (금오공과대학교 기계공학부)
  • Received : 2010.01.14
  • Accepted : 2010.03.18
  • Published : 2010.04.01

Abstract

The effect of incidence angle on the three-dimensional flow and aerodynamic loss in the tip leakage flow region downstream of a turbine rotor cascade has been investigated for two tip gap-to-chord ratios of h/c=0.0% (no tip gap) and 2.0%. The incidence angle is changed to be $i=-10^{\circ}$, $0^{\circ}$, and $5^{\circ}$. The results show that for $i=5^{\circ}$, secondary flows including the passage vortex are intensified noticeably, and there is a strong interaction between the passage and tip leakage vortices. For $i=-10^{\circ}$, however, the passage vortex is weakened significantly, so that there exists only a strong leakage-jet-like secondary flows near the casing wall. For h/c=0.0% and 2.0%, aerodynamic loss tends to increase with increasing i from $-10^{\circ}$ to $5^{\circ}$. A small increment of i in its positive incidence range results in a remarkable aerodynamic loss increase, while increasing i in the negative incidence range leads to a small change in the aerodynamic loss generation.

Keywords

References

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