Turbomachine Rotor Damping for Zero-Dephasing Vibration Modes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern turbomachine rotor modules are sensitive to aeroelastic phenomena, particularly vibration modes with zero dephasing, which lead to instabilities and reduced lifetime due to coupling between the fluid and structure, and existing damping systems are ineffective for these modes.
Innovation Solution
A turbomachine assembly with a damping device attached between two rotor modules, featuring a head with a radial external surface for friction contact and attachment feet connected to the modules, effectively damping vibrational movements by controlling tangential flexibility and amplitude, specifically addressing zero-dephasing modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing damping systems are used between blade platforms, then vibration modes with nonzero dephasing are dampened, but vibration modes with zero dephasing remain ineffective
Solution Approach 1:
The damping device moves from the traditional inter-platform location to a new dimensional position at the blade root level, where it can intercept and dampen zero-dephasing vibration modes that propagate through the rotor module attachments, thereby expanding the coverage of vibration modes without compromising existing damping capabilities
Solution Approach 2:
The damping device acts as an intermediary element installed between rotor modules at the attachment level, mediating the transmission of vibrational energy and providing a new pathway for energy dissipation that complements the existing inter-platform damping systems
2Productivity
If rotor modules operate in instability region, then aerodynamic performance is improved, but vibrational instabilities accelerate wear and reduce lifetime
Solution Approach 1:
The damping device provides preliminary anti-action by preemptively dampening zero-dephasing vibration modes before they can propagate through the rotor module and cause accelerated wear, thereby protecting the system's lifetime while allowing operation in the aerodynamically optimal instability region
Solution Approach 2:
The damping device converts the harmful vibrational energy generated during operation in the instability region into beneficial heat energy through friction and viscoelastic dissipation, thereby protecting the rotor module from wear while maintaining high aerodynamic performance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces vibrational instabilities across all vibration modes, including those with zero dephasing, thereby extending the lifetime and ensuring safe operation of turbomachine rotor modules by dissipating energy through friction and viscoelastic materials.
Implementation Method 1
a head, said head comprising a first radial external surface supported with friction against an internal surface of the platform of the first blade
Implementation Method 2
dissipating energy through friction and viscoelastic materials
Data Source
AI summary
The invention relates to a turbomachine assembly (1) comprising:a first rotor module (2) comprising a disk (21), a first blade (20) being mounted on the external periphery of the disk (21), the first blade (20) comprising a platform (25) and a support (27),a second rotor module (3), connected to the first rotor module (2) by means of at least two attachments (22) and comprising a second blade of smaller length than the first blade (20), anda damping device (4) attached to the attachment (22) between the first (2) and the second (3) rotor module so as to dampen their vibrational movements during operation, and comprising:a head (40) comprising a first radial external surface (42) supported with friction against the platform (25), andtwo attachment feet (41) extending on either side of the support (27) of the first blade (20).