Investigation of the Propeller Blade Failure Load and the Associated Spindle Torque - JIP BlaFex

Abstract

The IACS Polar Class Rules define the maximum propeller blade / ice interaction loads to be expected once in a life time of a ship. Beside the ice loads used for the scantlings of propeller blade, the ultimate blade failure load is also defined in order to check the connection between the blade and the hub and the pitching system. However, controllable pitch propeller makers claim that the failure load generates too high spindle torques and results in one or two hub sizes larger propellers being against their long term experience with existing designs and rising costs for new projects. Hence, IACS initiated a common Joint Industry Project (JIP) with different propeller makers called “BlaFex”. The main goal is an experimental validation of the blade failure load and the associated spindle torque calculation. At present, two blades have been tested in elastic and plastic range using different points of load application. In advance and parallel, numerical simulations have been performed and their results will be given and compared with the measurements. In this paper the obtained test results are presented and conclusions are drawn with respect to the next tests and numerical simulations.