A5046147202- Bladed Disk Vibration Dynamics
- Brake Systems and Friction Analysis
- Dynamics and Control of Mechanical Systems
- Turbomachinery Performance and Optimization
- Structural Health Monitoring Techniques
- Tribology and Lubrication Engineering
- Adhesion, Friction, and Surface Interactions
- Vibration and Dynamic Analysis
- Mechanical stress and fatigue analysis
- Composite Structure Analysis and Optimization
- Probabilistic and Robust Engineering Design
- Railway Engineering and Dynamics
- Gear and Bearing Dynamics Analysis
- Hydraulic and Pneumatic Systems
- Model Reduction and Neural Networks
- Mechanical Engineering and Vibrations Research
- Electromagnetic Launch and Propulsion Technology
- Real-time simulation and control systems
- Statistical and Computational Modeling
- Vehicle Noise and Vibration Control
- Structural Engineering and Vibration Analysis
- Mathematical Biology Tumor Growth
- Advanced MEMS and NEMS Technologies
- Metal Forming Simulation Techniques
- Seismic Performance and Analysis
University of Stuttgart
2014-2024
University of Arizona
2015
Polytechnic University of Turin
2015
Numerical path continuation is commonly applied to determine how limit states of dynamical systems evolve with a free parameter. For high-fidelity models complicated nonlinear systems, the sequential nature inherent can become an unsurmountable obstacle. In present work, we propose new paradigm for obtaining targeted solution curves in parallelized way. The point departure low-fidelity model, which lower order and/or neglects certain nonlinear/coupling terms. simplifications must be as...
Thin-walled structures clamped by friction joints, such as aircraft skin panels are exposed to bending-stretching coupling and frictional contact. We propose an original sub-structuring approach, where the system is divided into thin-walled support regions, so that geometrically nonlinear behavior relevant only in former, contact latter. This permits derive reduced component models, principle, with available techniques. The Hurty-/Craig-Bampton method, combined interface reduction relying on...
For the first time, a fully-coupled Harmonic Balance method is developed for forced response of turbomachinery blades. The applied to state-of-the-art model turbine bladed disk with interlocked shrouds subjected wake-induced loading. recurrent partial opening and closing pre-loaded shroud contact causes softening effect, leading turning points in amplitude–frequency curve near resonance. Therefore, coupled solver embedded into numerical path continuation framework. Two variants are...
Abstract In this paper, a validation approach for turbine blade component test with frictional contacts is presented. The investigated system derived from high cycle fatigue setup, where base-excited in the clamped foot. setup has been extended by laser scanning vibrometry, force measurement platform, and feedback-controllers both level phase. At first, conventional of linearized model performed at low amplitudes to ensure correct modal basis reduction. After that, nonlinear behavior around...
Harmonic Balance is probably the most popular method for computing both periodic and quasi-periodic vibrations. To treat hysteresis in case, a marching procedure commonly used where evolution law that governs incremented discrete time until steady cycle reached. In present work, this generalized to case. The numerical examples demonstrate superior computational performance of proposed approach over state-of-the-art. latter requires representation internal variables defining state, which have...
Abstract In this paper, a validation approach for turbine blade component test with frictional contacts is presented. The investigated system derived from high cycle fatigue setup, where base-excited in the clamped foot. setup has been extended by laser scanning vibrometry, force measurement platform and feedback-controllers both level phase. At first, conventional of linearized model performed at low amplitudes to ensure correct modal basis reduction. After that, nonlinear behavior around...
Abstract In this paper, an experimental test rig for friction saturated limit cycle oscillations is proposed to provide a validation basis corresponding numerical methods. Having in mind the application of turbine blades, instrumented beam-like structure equipped with adjustable velocity feedback loop and dry frictional contacts designed investigated. After dimensioning by means simplified one-dimensional beam model time domain simulations, specific requirements design contact, excitation...
Abstract Measurements revealed the contribution of multiple traveling waves to flutter vibrations bladed disks. Saturated vibration, whether in this multi-wave or its better-understood single-wave form, is a nonlinear phenomenon. However, it still not understood what physical origin relevant nonlinearities are, and under conditions vibration occurs. Recent theoretical work suggests that can be explained by strongly frictional inter-blade coupling. The verity hypothesis strictly limited...
Since the first nonlinear forced response validation of frictionally coupled bladed disks, more than 20 years have passed, and numerous incremental modeling simulation refinements were proposed. With present work, we intend to assess how much improved since then. To this end, findings an exhaustive campaign designed systematically validate vibration prediction for different friction joints at blade roots, interlocked shrouds under-platform dampers. An original approach identification crucial...
Abstract Dry friction devices such as underplatform dampers are commonly included in turbine bladed disks designs to mitigate structural vibrations and avoid high cycle fatigue failures. The design of frictionally damped requires adequate models represent the contact. A widely used approach connects contact node pairs with normal tangential springs a Coulomb law. This simple model architecture is effective capturing softening behavior typically observed on structures subjected increasing...