Computations of flows over a turbine blade

Abstract

To meet the needs of e©cient turbine blade designs, computational §uid dynamics (CFD) predictions of a complex three-dimensional (3D) §ow ¦eld in turbine blade passages have been incorporated in the design process during the last decade. Owing to the numerous advantages possessed by a 3D CFD technology, many industries already use a 3D blading technique in the design process of turbomachines. In addition, blade lean and sweep have been implemented to increase the blade row e©ciency. Experimental studies have shown some advantages of these features. However, most of the experimental results were combined with other features together as well, thus making it di©cult to determine the e¨ects of individual superior features. The development of CFD techniques has made it possible to do 3D turbulent §ow analyses in a very short time. In this study, numerical studies are presented to demonstrate the sweep e¨ects on a transonic compressor airfoil. The purpose of this study is to investigate the sweep e¨ects without changing other compressor blade features, i.e., keeping the blade out §ow angles and section shapes to be the same at design sections for all cases. Through this study, the sweep e¨ect in a transonic compressor rotor blade was tested. The results showed that the sweeps redistribute the §ow reducing the secondary §ow loss, depending on the baseline. It was shown that the forward sweep reduces the tip loading in terms of the static pressure coe©cient.