Papers Published

  1. Crawley, E. F. and Hall, K. C., OPTIMIZATION AND MECHANISMS OF MISTUNING IN CASCADES., Journal of Engineering for Gas Turbines and Power, Transactions of the ASME, vol. 107 no. 2 (1985), pp. 418 - 426 .
    (last updated on 2007/04/10)

    An inverse design procedure has been developed for the optimum mistuning of a high bypass ratio shroudless fan. The fan is modeled as a cascade of blades, each with a single torsional degree of freedom. Linearized supersonic aerodynamic theory is used to compute the unsteady aerodynamic forces in the influence coefficient form at a typical blade section. The mistuning pattern is then numerically optimized using the method of nonlinear programming via augmented Lagrangians. The objective of the mistuning is to achieve a specified increase in aeroelastic stability margin with a minimum amount of mistuning. It is shown that a necessary but not sufficient condition for aeroelastic stability is that the blades be self-damped.

    TURBOMACHINERY - Blades;FANS - Mathematical Models;ROTORS - Performance;AERODYNAMICS;