As the size of the wind power becomes larger, the development of the assembly type wind power which is advantageous in transportation and installation is active. This advantage comes from the economic point of view, and the stiffener is applied to the inner side, so that the safety is high. Large wind power require door openings for maintenance. The door opening has an irregular cross-section, and an excessive stress active due to the door opening. In this paper, the stresses occurring around the door opening was analyzed. As a result, small stress values were appeared in the tower, as the number of stiffeners were increased. Also, stress values were decreased a little in the tower as the opening shape become to ellipse was closer.

Abstract
 1. 서론
 2. 본론
  2.1 설계기준
  2.2 풍력발전 타워 설계하중 해석
  2.3 설계하중 해석이론
  2.4 경계조건
  2.5 해석 결과
 3. 결론
 References

• 박상현(Kunsan National University) | Sang-Hyun Park
• 박명성(Kunsan National University) | Myoeng-Seong Park
• 김영철(Kunsan National University) | Young-Chul Kim
• 백태현(Kunsan National University) | Tae-Hyun Baek Corresponding Author