Apparatus and method of active flutter control
US6195982A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1998 |
| Grant date | Mar 6, 2001 |
| Priority date | — |
| Expiry date | Dec 30, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D29/668
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A system for controlling aeromechanical instability or flutter in turbofan engines having fan blades employs a sensor, such as an off-blade static pressure sensor or proximity detector mounted on a turbofan engine at an inlet of a rotor of the engine for generating a signal to detect resonance of the turbofan blades at frequencies associated with flutter. A controller is coupled to the sensor for generating by spatial Fourier decomposition from the sensor signal a command signal comprising a real time amplitude component and a spatial phase of disturbances of a predetermined nodal diameter and coincident with a natural frequency of resonance of a predetermined structural mode of the fan blades in the stationary frame. An actuator, such as a bleed valve or acoustic speaker, is mounted on the turbofan engine for damping flutter dynamics in response to the amplitude of the command signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.