A theoretical model for flow about a circular-arc aerofoil with separation

• Main Author: Cyr, Stephane
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-1992
• Subjects: Mechanical engineering
• ISBN: 9780315748644; 0315748648

The aim of the present research is to develop a theoretical model that could predict the trailing-edge separation over a circular-arc aerofoil and its effect on the pressure distribution, and on the lift. The model uses sources, in a potential flow, to simulate the effect of the separated region on the pressure distribution. An integral method, turbulent boundary-layer development, combined with the irrotational pressure distribution on the circular-arc predicts the point of separation. To make sure that trailing-edge separation is present alone and mostly to avoid any difficulties in predicting the boundary-layer flow after reattachment, the aerofoil is studied at design incidence. Two different circular-arc aerofoils were tested; one of 10% and one of 18% camber. The calculation for the 10% aerofoil did not predict any separation at design incidence, which was confirmed experimentally. The theoretical model predicted the right position of separation for the 18% aerofoil. It also provided a good simulation of the pressure distribution, including the right value for the base pressure and a good prediction of the lift. It follows that the pressure distribution when integrated, gives a good estimate of the pressure or form drag. (Abstract shortened by UMI.)