Simulation Study On Bird-Strike Mechanical Damage Of Fan Blades For Aero-Engine

Based on the basis of the results of previous studies on the impact of birds, we studied bird strike on aero-engine blades deeply and explore the mechanism of high-speed rotating fan blade soft material injury. With modern and advanced numerical method, we conducted systematic research on FOD damage for high-speed rotating blades and get some meaningful conclusions. Calculated by the use of an iterative optimization software and get the excellent solution of the model parameters. Bird strike blade is random, the bird’s flight speed and impact area of uncertainty both as research object. Using mathematical statistics ternary number interval theory, determine the generalized probability density function method for structure stress of birds hit the blade structure, and get the generalized reliability formula of bird strike fan structure. The main contents are:1. A brief introduction to bird strike aircraft’s research background, the significance and research status quo at home and abroad. Then studied the theoretical basis and numerical methods of bird strike impact elastic dynamics and impact of foreign objects.2. Describe the soft material injury’s mechanism of high-speed rotating fan blades. Combined with numerical calculation, obtained the influences of relative impact of relative impact parameters on the blades caused by blade complex motion. The larger body translation velocity, or the greater the angular velocity, or impact location near the tip, then the initial impact of foreign objects relative velocity is larger, so the degree of blade damage is greater. The injury patterns will also change. The larger the angle, the greater the contact impact force and the damage to the blade.3. For the bird constitutive parameters of CFM56-5B model, we conduct finite element correction on it. Put the engine fan blades’ entity as a study object, establish the numerical simulation of an ideal model, and get a series of blade deformation maps, stress and displacement curve. In the end, we find the mechanical damage of bird strike CFM56-5B engine fan blades and the impact velocity and position has a great relationship.4. Calculating using ternary interval number theory. Determined the generalized probability density function method of bird strike blade structure stress and the probability generalized reliability for calculating formula of the blade structure.