Aerodynamic study on straight, arc-swept and twisted stationary linear cascade blades

Abstract

A computational investigation has been carried out on the effects of sweep and twist in stationary linear cascades. Circular arc sweep has been applied to the datum cascade of straight cylindrical blades, i.e. spanwise constant stacking line curvature was prescribed. Positive sweep was applied near the endwalls, and the sweep angle distribution was symmetrical to the midspan plane. The straight and the arc-swept blades were studied at low, near-design, and high incidence angles of the straight blading. Twisted versions of the straight and the arc-swept blades were studied for spanwise constant inlet flow angle. The studies demonstrated the benefits of circular arc sweep for both untwisted and twisted blade rows, such as local loss reduction and uniformisation of cascade outlet axial velocity profile. Blade twist was found favourable from the aspect of endwall separation zone reduction.