An analysis is carried out for the vortex core structure particularly on circumferential velocity in plateau region and its roll-up effects on the downwash behind wings of elliptic circulation distribution.
Widely used analytical models of Betz, Rankine and Lamb are generally not in acceptable agreement with experimental data of the maximum circumferential velocity, due to the fact that rotational energy and integral invariants are not satisfied. Thus, an attempt is made to satisfy them by applying, modifying and matching the conical flow model solution, because the variation of flow properties along free stream direction is very small compared to radial direction. The results indicate the existence of so called the overshoot region of circulation in the inner core.
The analysis of the effect of plateau region downstream of wing related to the downwash velocity shows that if AR/C$_L$ is greater than 9.107, the effect of plateau region on wing is negligible.
타원 양력 분포를 갖는 날개 뒤의 plateau 영역에서 순환 속도 분포와 plateau 영역이 날개에 미치는 roll-up 효과를 해석 하였다.
널리 사용 되는 model 들은 inner core 영역에서 속도 분포를 적절히 예측 하지 못 한다.
이를 개선 하기 위하여 conical flow 해를 도입해서 새로운 모형을 얻었다.
또 이 결과를 이용 해서 만약 $AR/C_L$ >9.107 이면 plateau 영역의 날개에 대한 영향이 충분히 작음을 보였다.
