Application of an unsteady Navier-Stokes solver to transonic turbine designThis study presents a numerical evaluation of the performance of the first stage of a new-generation turbine design. The numerical method solves the two-dimensional Navier-Stokes equations using a system of patched grids. Three-dimensional effects of stream-tube contraction are also modeled. The study focuses on the effects of axial gap variation on the unsteady rotor-stator interactions and on stage performance. Results are presented for three different axial gaps. The results indicate that the unsteady interactions can be very large in this design. These interactions affect not only the stage efficiency but also substantially alter the time-averaged features of the flow. In particular, for the case of the smallest axial gap, it was found that there was an unsteady shock on the stator suction surface which spanned the gap region and impinged upon the moving rotor airfoils.
Document ID
19910059631
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Rangwalla, Akil A. (NASA Ames Research Center Moffett Field, CA, United States)
Madavan, Nateri K. (NASA Ames Research Center; Sterling Federal Systems, Inc. Moffett Field, CA, United States)
Johnson, Paul D. (Pratt and Whitney Group West Palm Beach, FL, United States)