가스터빈 블레이드 내부 배열별 핀-휜 지름 변경에 따른 냉각 성능 특성 변화

국문 초록 (Abstract)

가스터빈 블레이드의 핀-휜 배열의 국소 냉각 성능을 조절하기 위하여 핀-휜의 지름 변경에 따른 효과를 분석하였다. 엇갈림 배열 핀-휜이 설치된 내부 유로의 3열의 지름이 다른 경우의 유동 및 열전달 특성 변화를 수치해석을 통해 분석하였다. 엇갈림 배열의 핀-휜이 설치된 기존 형상, 3열의 핀-휜 지름이 20% 증가된 형상, 3열의 핀-휜 지름이 40% 증가된 형상을 각각 비교하였다. 수치해석 결과 핀-휜 배열의 지름이 증가하는 경우 내부 유동의 유속이 가속되었으며, 3열의 핀-휜 지름이 향상된 영역의 국소 열전달 분포가 기존 형상에 비해 증가하는 것을 확인하였다. 또한 바닥면의 평균 열전달 분포가 증가하는 것을 확인하였다. 반면 증가된 지름의 크기로 인해 압력손실은 증가하였으나, 열성능계수는 1.2x 형상에서 0.4% 가량 증가하였다. 이를 통해 향후 가스터빈 핀-휜 냉각 유로 설계 시 핀-휜 지름 크기변경을 통해 냉각성능을 국소적으로 조절할 수 있는 것으로 판단된다.

다국어 초록 (Multilingual Abstract)

The effect of different diameters of pin-fin array was analyzed to control the cooling performance of internal passage of the gas turbine. Numerical simulations were conducted to determine the flow and thermal characteristics of two different diameter of pin-fin array effect. A staggered pin-fin array with same pin-fin diameter, 1.2x pin-fin array with 20% large pin-fin diameter at the bottom 2 array, and 1.4x pin-fin array with 40% large pin-fin diameter at the bottom 2 array were compared. The results showed that higher velocity was observed in large pin-fin array cases and different local heat transfer distributions were observed near large pin-fin arrays. Furthermore, the heat transfer distributions on the endwall increased. The friction factor increased owing to the installation of larger pin-fin, and thermal performance factor was increased to 0.4% in 1.2x pin-fin array. Therefore, installation of larger diameter pin-fin will be helpful in controlling the cooling performance of pin-fin array internal passage of gas turbine blades.

목차 (Table of Contents)

• 초록
• Abstract
• 1. 서론
• 2. 연구 방법
• 3. 연구 결과
• 4. 결론
• 참고문헌(References)

참고문헌 (Reference)

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