A Study of Hydroelastic Stability of Partially Cavitated Hydrofoils by Application of Quasisteady Theory

摘要

This report presents a stability analysis for partially cavitated hydrofoils, where the foil is represented by a flat plate. In the hydrodynamic force and moment representation, only the quasi-steady and apparent-mass contributions are retained; the wake effects, essential for unsteady theory, are neglected. The resulting flutter boundaries are compared to those obtained by applying the complete unsteady solution. It is shown that the behavior at low reduced frequencies is in agreement with the unsteady solution. In particular, the critical density ratio, which is (effectively) the lowest value of the density ratio at which flutter will occur, can be calculated exactly from the quasi-steady theory. (Author)