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Blade flutter is one of the major problems that designers of modern gas-turbine engines face. In this paper, a study of the influence of the design parameters on prediction of blade flutter in compressors of gas-turbine engines is presented. As a rule, the flutter of compressor blades is predicted using simplified criteria based on the experience of designing and refining engines. These empirical and probabilistic criteria are not applicable to evaluation of the flutter since the parameters in question are not among the decisive parameters for simplified criteria. In this work, the energy method is used. It is shown that the inter-blade tension value has a significant influence on the blade flutter prediction, while the effect of other design parameters under investigation on the blade flutter prediction is insignificant.

Panel flutter is a phenomenon of self-exciting vibrations of skin panels of flight vehicles moving at high speeds. There are two types of panel flutter. The first one is the coupled-mode flutter, which is caused by the interaction of two panel eigenmodes. The second type is the single-mode flutter, in this case the coalescence of eigenfrequencies and a significant change in the oscillation mode shape does not take place. The stability of the infinite series of thin elastic rectangular plates simply supported along all edges is investigated in this study. The non-zero flow yaw angle with supersonic leading edge is considered. We use potential flow theory to derive expression for the unsteady aerodynamic pressure distribution over the oscillating plate. The plate motion equation, after the substitution of expression for unsteady aerodynamic pressure, with simply supported boundary conditions, is an integro-differential eigenvalue problem for finding complex eigenvalues. We use the Bubnov–Galerkin procedure for finding eigenvalues. Thus, the flutter criterion is the sign of imaginary part of eigenvalue. Flutter boundaries for the first eigenfrequencies were computed for non-zero yaw angles We show how the single-mode and coupled-mode flutter boundaries are changed with the change of the yaw angle.