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Projects: Projects for Investigator
Reference Number EP/K005456/1
Title Active Vibration Control of Parametrically Excited Systems
Status Completed
Energy Categories Renewable Energy Sources(Ocean Energy) 10%;
Not Energy Related 90%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr M Ghandchi Tehrani
No email address given
School of Engineering Sciences
University of Southampton
Award Type Standard
Funding Source EPSRC
Start Date 30 April 2013
End Date 29 April 2015
Duration 24 months
Total Grant Value £98,985
Industrial Sectors Aerospace; Defence and Marine; Construction; Transport Systems and Vehicles
Region South East
Programme NC : Engineering
 
Investigators Principal Investigator Dr M Ghandchi Tehrani , School of Engineering Sciences, University of Southampton (100.000%)
  Industrial Collaborator Project Contact , Ove Arup & Partners Ltd (0.000%)
Project Contact , AgustaWestland (0.000%)
Web Site
Objectives
Abstract This project considers active vibration control of parametrically excited systems (PES). The problem is to develop control strategies for the suppression, or enhancement, of parametric resonances in engineering systems. Active control has the potential to control large amplitudes of vibration and modify the dynamics of the system very efficiently. It is particularly suitable for PES since the dynamics of PES are periodic-time dependent. The appearance of the periodic-time-dependent parameter in the dynamic equation results in a complex response including inherent instabilities, or combined resonances of summed or difference type. Understanding the dynamics of PES and its control is thus the main objective of this research.The control strategy that will be used for PES is based on the receptance method developed by the applicant for linear time-invariant systems. The method has significant advantages, since there is no requirement for knowledge of system matrices, no requirement for model reduction techniques and no requirement for observers to estimate the unmeasured states. The method is entirely based on the measured vibration data; therefore the dynamics of the actuators, sensors and filters are all included in the design of the controller. Other control strategies based on the Floquet theory will also be developed. The control techniques will be implemented on a cable-supported structure, representing a cable-stayed bridge, to demonstrate the practical application of the active control on PES.Many engineering structures are subjected to parametric excitation, which is produced by some external loads interacting with the structure. In civil engineering, Aratsu Bridge in Southern Japan is an example where parametric resonance was the origin of the cracks close to the anchorages. Parametric resonance occurs when the structural frequency coincides with a specific ratio of the parametric excitation frequency. For instance in the Skarnsundet Bridge in Norway, a vertical deck frequency was exactly twice the fundamental cable frequency. Vibration control can be achieved by moving the structural frequency away from that specific ratio using pole placement techniques.In aerospace, parametric resonance can cause flutter of airplane wings due to the interaction of the wing with the aerodynamic loads. Recently, a fatal accident occurred involving a prototype of a business jet due to the tail-plane flutter, and the research aims to develop methods by which such instability can be controlled.In marine engineering, parametric resonance can occur in riser systems due to the interaction of the risers with surface waves. The undesirable dynamic behaviour of these risers can be avoided using tension control. If parametric excitation is not included in the design of these risers, the wave induced vibration can result in instability and even catastrophic failure, thereby causing severe environmental and economic damage so that a more flexible method of active control would make the system safer. The research will also be beneficial in the design of the energy converters such as floaters since it can enhance the parametric resonance, which is used to extract significant amount of power from the wave energy
Publications (none)
Final Report (none)
Added to Database 08/10/12