Numerical Investigation of Transitional Flow Through a Low-Pressure Turbine Cascade

Abstract

Subsonic transitional flow through a low-pressure turbine cascade is investigated numerically by a comprehensive series of computations. Large-eddy simulations are performed at an inlet Mach number of 0.06 for a range of Reynolds numbers. The calculations employ a fourth-order compact scheme to represent spatial derivatives, which is used in conjunction with a sixth-order low-pass Padetype non-dispersive filter operator. A time-implicit approximately-factored finite-difference algorithm is utilized, and Newton-like subiterations are applied to achieve second-order temporal and fourth-order spatial accuracy. The computational domain is partitioned into a series of zones which were distributed on individual processors of a massively parallel computing platform. Solutions were obtained for chord inlet Reynolds numbers of 2.5, 5.0, and 10.0× 10. Features of the flowfields are examined, and large-eddy simulations are compared with twodimensional computations, and with experimental data.