Experimental Study of the Three-Dimensional Flow Field in an Annular Turbine Nozzle Guidevane

The paper describes the experimental investigation of the three-dimensional flow through a low-speed, low aspect ratio, high turning annular turbine nozzel guide vane. The flow is explored by means of double-head, four-hole pressure probes in twelve axial planes from upstream to far downstream of the blade row. The results are presented under the form of contour plots and spanwise pitch-averaged distributions of losses, flow angles, and static pressure distributions. The concept of presenting the evolution of the endwall boundary layer under the form of streamwise and crossflow velocity components is discussed in detail.