State-of-the-Art Finite Element Modeling of Rotorcraft Main Rotor Blade for Bird Strike Damage Analysis

Abstract

This paper demonstrates the state-of-the-art composite modeling methodology to investigate the bird strike phenomenon using available numerical bird models through experimental tests and simulation tools. The present work is based on the application of nonlinear explicit finite element analysis to simulate the response of rotorcraft main rotor blade root end under high velocity impact load. The damage behavior of blade made of composites under soft body impact depends upon bird size, blade size, blade span-wise location of impact and bird orientation with respect to hitting location, blade rotational speed and rotorcraft cruise speed. Bird model is considered as hydrodynamic with length-to-diameter ratio of 2. A bird strike event is characterized by loads of high intensity and short duration. A transient explicit nonlinear finite element-based impact analysis using Autodyn has been carried out to predict bird strike resistance to withstand 1.0 kg bird at critical flight condition. Numerical analysis indicates that blades do not tear which agrees well with the physical test conducted.