Identification of distributed loads on propellers based on strain modal

Most noise and vibration produced during a ship's operation is attributable to the surface forces exerted on the propeller. Direct measurement of the load via sensors is challenging due to technological and economic limitations. This paper carries out an initial investigation on the distributed load identification technology of the propeller in the frequency domain and the generalized orthogonal domain, using the single-blade propeller as the research object and fully utilizing the unique benefits of Fiber Bragg Grating (FBG) sensors, including their small size, lightweight, resistance to corrosion, and ease of forming a sensing network. Simultaneously, the identification model for the propeller's distributed load is formulated based on the strain model and the Chebyshev orthogonal polynomial. To confirm the efficacy and precision of the developed model, the propeller's harmonic response is analyzed using the ANSYS workbench. Ultimately, the amplitude of the stress on the propeller is determined through the integration of simulation and experiment. The validity and accuracy of the model established are further confirmed by the identification error, which is <11 %.