Bird Strike on Jet Fan Introduction Modelling of Bird Strike using EUROPLEXUS Full Lagrangian Approach Bird modelled by SPH elements (porous gelatine ma terial) - Europlexus is a general Finite Element software for non-linear dynamic analysis of Fluid-Structure systems subjected to fast transient dynamic loading. - Deal with large displacements/rotations and large strains. Methodology 1 st analysis in a rotating frame for the rotor und er centrifugal loading 2 nd analysis in a fixed frame: rotor + stator + bir d Initial stress distribution Deformed rotor Initial velocity and acceleration Power Reducer Rotor Dynamics Introduction Two coaxial shafts terminated by one pinion 2 times: 1 pinion coupled to three satellites mounted on a short shaft 6 shafts coupled with a bell Bell coupled with a propeller shaft Object Critical speeds of each shaft and of the whole system Torsion bending coupling Bending and axial loads on the propeller Input Pinion Fourier bi-harmonic elements 0 and 1 diameter Axial, torsion and bending Supported by ball bearings (axial and radial stiffness) Input Pinion Torsional mode and Bending mode Propeller shaft including the bell Shaft : Fourier biharmonic Bell : 3D super-element Validated with respect to a 3D model With rigidification due to the gear connection Propeller shaft including the bell Bell : 3D super-element With rigidification due to the gear connection Propeller shaft including the bell Validation Second stage shafts Beam models : short and long shafts Whole model Includes all the 8 shafts Gearing connection Casing: 3 additional super-elements Gear connections 12 gear connections (global model, constraints) Pressure angle Teeth flexibility (global model) relative displace ment Campbell diagrams 1:1 1: :11 Eigenmodes of the whole system Transient Analysis Imposed rotational speeds versus time Imposed torques Turbine Resisting torque at the propeller level Imposed geometrical errors at the gear connections ij = cos ( k (t) t + ki ) Transient Analysis Results: torques with error effect Conclusions Coupling of different modelling techniques: beam, Fourier, 3D and super-elements Bending and torsion behaviours have to be simult aneously taken into account for correct prediction Global model for gear connections taken into acco unt geometrical errors SAMCEF/ROTOR is adapted to study the Rotor Dynamics of Power Reducer Systems Cryogenic Turbopump Rotor Dynamics Introduction Rotor model Linking devices Casing model Critical speeds Sensitivity Harmonic response Transient response Rotor Model Axisymmetrical 2D Fourier model Semi-discretization in Fourier series and Modeling in a Meridian Plane with triangular and Quadrangular Volume elements. Harmonics with one Diameter coupled by the Gyroscopic Effect. Gyroscopic effect Pre-stress Anisotropy Rotor Model Material Properties function of temperature Equivalent properties for the blades Youngs Modulus Density Rotor Model Internal boundary conditions Locally free relative radial or circumferential displace ments Locally free relative axial displacements Rotor Model Super-element (Craig-Bampton method) Boundary nodes: bearings, seals, fluid forces, unbal ances Normal modes up to Hertz Linking Devices Stiffness and damping coefficients function of the rotational speed Labyrinth seals, smooth seals Alford s effect (turbines) Aerodynamic forces Added mass effect (fluid) Duplex Ball Bearings (clearances) Casing model Super-element (Craig-Bampton method) For different temperature maps Boundary nodes: bearings, seals, fluid forces, fixations Normal modes Casing model Validation of the super-element : free-free normal modes Mass Inertia Rigid body modes Eigenfrequencies Eigenmodes Modal stresses Critical Speed Analysis Campbell s Diagram Critical Speed Analysis Critical mode Critical Speed Analysis Energy distribution: strain, kinetic, dissipation Percentages (linking devices) Density (structure) Sensitivity Analysis Sensitivity of the eigenvalues with respect to parameters Variatio n Parameters: joints stiffness, damping coefficients Statistical Analysis Gaussian distribution Confidence range 1 s, 2 s, Harmonic Response Set of unbalances Non synchronous loads Harmonic Response Radial synchronous fixed force on the inducer Non synchronous 10 radial force on the impeller Harmonic Response Non linear response : clearances in bearing support s Multiple solutions in some frequency ranges