Effect of Pitch Variation on a Propeller Frequencies Analytically, Numerically and Experimentally

In this paper, effect of pitch variation on vibrations of a propeller variable pitch is studied numerically and experimentally. The free vibrations equations of a propeller blade were extracted using the Galerkin method. A three-dimensional scanner was utilized to obtain blade profile and static trust with the aim of determining propeller loading status. To obtain modal analysis, the simulation analysis was done using Abaqus software in rotating condition, and results were validated with experimental modal test in static status. Both of experimental and analytical methods results represent that with increasing pitch, the variations of natural frequency are reduced and increased at odd and even frequency modes, respectively. Considering the campbell diagram, no resonance problem was observed in the case of the propeller blade, at working period.