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Aerodynamic Shape Optimization of Helicopter Rotor Blades in Hover Using a Continuous Adjoint Method on Unstructured Meshes

비정렬 격자계에서 연속 Adjoint 방법을 이용한 헬리콥터 로터 블레이드의 제자리 비행 공력 형상 최적설계

  • 이상욱 (한국과학기술원 항공우주공학과 대학원) ;
  • 권오준 (한국과학기술원 항공우주공학과)
  • Published : 2005.01.01

Abstract

An aerodynamic shape optimization technique has been developed for helicopter rotor blades in hover based on a continuous adjoint method on unstructured meshes. The Euler flow solver and the continuous adjoint sensitivity analysis were formulated on the rotating frame of reference for hovering rotor blades. In order to handle the repeated evaluation of the design cycle efficiently, the flow and adjoint solvers were parallelized using a domain decomposition strategy. A solution-adaptive mesh refinement technique was adopted for the accurate capturing of the tip vortex. Applications were made for the aerodynamic shape optimization of Caradonna-Tung rotor blades and UH60 rotor blades in hover. The results showed that the present method is an effective tool to determine optimum aerodynamic shapes of rotor blades requiring less torque while maintaining the desired thrust level.

비정렬 격자계에서 continuous adjoint 방정식을 사용하여 제자리 비행을 하는 헬리콥터 로터 블레이드에 대한 공력 형상 최적설계 기법을 개발하였다. 효율적인 민감도 계산을 위해 회전좌표계에서 continuous adjoint 민감도 해석 기법을 유도하였다. 설계과정의 반복적인 수치계산의 효율을 높이기 위해서 영역 분할 기법에 기반을 둔 병렬처리 기법을 도입하였다. 끝단 와류의 정확한 포착을 위해서 끝단와류를 따른 격자적응을 수행하였다. 이러한 방법은 Caradonna와 Tung의 실험형상 및 UH60 헬리콥터 로터 블레이드의 공력 최적설계에 적용되었으며, 본 연구에서 사용된 최적설계 기법을 이용하면 일정한 추력을 유지하면서 요구동력을 현저하게 줄일 수 있음을 보였다.

Keywords

References

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