Aeroelastic Stability Analysis of Supersonic Cascades

Abstract

This paper presents three solutions for the analysis of supersonic flow past oscillating cascades with subsonic leading-edge locus. A quite elementary solution is first developed for the case of slowly oscillating finite and infinite flat plate cascades which provides simple analytical expressions for the unsteady pressure distributions. Comparisons with other solutions show generally excellent agreement. Furthermore, a previously developed linearized characteristics solution for finite flat plate cascades is applied to the case of superresonant blade motions. Again, the unsteady blade loading distributions are found to be in good agreement with Verdon’s recent infinite cascade solution for this case. Finally, a nonlinear method of characteristics solution for finite cascades is described which permits the analysis of blade thickness effects on flutter. At this time, only the inlet and passage flow computations have been completed which are compared with the available experimental information.