Unsteady viscous flow causing rotor-stator interaction in turbines, part 1: Data, code pressure

A coupled experimental and computational study of the effects of the nozzle wake-rotor interaction is carried out to understand the cause and effects of the unsteady flow in turbine rotors. The paper is organized in two parts . Part 1 deals with the experimental and numerical program and interpretati on of the blade pressure field. The experiment was carried out in a low-spe ed turbine at 22.6% of the nozzle chord spacing between the rotor and the n ozzle, The laser Doppler velocimetry (LDV) data, acquired earlier, Is integ rated with the dynamic pressure measurements and numerical simulation to pr ovide an integrated interpretation. A systematic study has been carried out to evaluate the effect of the turbulence model and artificial dissipation on the accuracy of the numerical prediction. The steady flowfield, unsteady pressure at design and off-design conditions on both blade surfaces, and t he hub are presented, interpreted, and compared with the predictions from t he Navier-Stokes code. The predictions are in a good agreement with the dat a. The second part deals with the integrated interpretation of the unsteady velocity and pressure field, as well as the flow physics associated with t he nozzle wake transport and decay.