Impact of the Reduced Frequency on Pressure Distribution on the Lower Surface of a Supercritical Airfoil during Pitch-Pause-Return Motion
Author(s):
Article Type:
Research/Original Article (دارای رتبه معتبر)
Abstract:
Effects of reduced frequency, pause duration and stop angle on pressure distribution on the lower surface of thin supercritical airfoil undergoing the pitch-pause-return maneuver have been studied. The experiments have been performed in a subsonic wind tunnel for a fixed mean angle of attack and at constant amplitude. The reduced frequencies were from 0.01 to 0.12, and three stop angles were chosen during upstroke motion in below stall, near stall and post stall regions. For all angles of attack below the static stall, the pressure distributions are nearly identical at the rear quarter chord on the lower surface. For beyond the stall angles, the lower surface pressure distributions are observed to remain unchanged from the leading edge downstream to x⁄c=0.15. Also dynamic results show that the behavior of pressure distribution at the lower surface taps for all reduced frequencies and pause durations, are identical from leading edge to x⁄c=0.70 and are higher than the static values at zero angle of attack. However, the lower surface pressure distributions have been observed to be entirely different at the rear 30% chord for various pause angles, which can be deemed to be the signature of the unsteady Gortler vortices.
Keywords:
Language:
Persian
Published:
Amirkabir Journal Mechanical Engineering, Volume:52 Issue: 4, 2020
Pages:
141 to 150
magiran.com/p2106223
دانلود و مطالعه متن این مقاله با یکی از روشهای زیر امکان پذیر است:
اشتراک شخصی
با عضویت و پرداخت آنلاین حق اشتراک یکساله به مبلغ 1,390,000ريال میتوانید 70 عنوان مطلب دانلود کنید!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی نامحدود همه کاربران به متن مطالب تهیه نمایند!
توجه!
- حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران میشود.
- پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانههای چاپی و دیجیتال را به کاربر نمیدهد.
In order to view content subscription is required
Personal subscription
Subscribe magiran.com for 70 € euros via PayPal and download 70 articles during a year.
Organization subscription
Please contact us to subscribe your university or library for unlimited access!