Non-Newtonian flow over the trailing edge of an airfoil

Results are presented from an experimental study of flow over a C4 airfoil in a shear-thinning non-Newtonian flow. A digital particle image velocimeter (DPIV) was used to measure the instantaneous velocity field in the trailing edge region of the airfoil placed at an angle of attack of 35°. This flow field is relevant to that occurring around hydrofoils of agitators used for mixing slurries. It is shown that the Kutta condition was not satisfied at the trailing edge region. This implies a low lift force coefficient for the airfoil. Features including velocity distributions and strain rate are presented based on measurement using the DPIV technique.