Hydroelastic Effects on Propeller Blades in Steady Flow

Abstract

By early 70 's the steady hydroelastic response of the screw propeller's blade had been estimated by simple1) and improved2) methods based on the beam theory. Later it has been estimated by various FE methods, applying thin3) and thick shell4) or plate5) FE, as well as more sophisticated curved solid FE6). However, the present rules of most classification societies still include formulas for the required minimum blade thickness, which seem to have been derived from the cantilever beam theory. This thickness rule should be satisfied at 0.25R and 0.6R span positions. In addition some special strength estimations that have been carried out for propellers of unconventional form should be necessarily submitted for approval. In some literature we can find analyses of the distribution of blade stresses and deflections for ahead and astern motion in order to verify the reliability of applied thickness distribution. Atkinson and Glover7) presented interesting results concerning various hydroelastic effects and their influences on the hydrodynamic performance of propel- lers in the cases of different propeller outline and thick- ness distribution. Lin and Lin8) carried out coupled FE -lifting surface analysis of the effect of thickness on the *