Aeroelastics

Overview

AeroTex has experience in addressing a range of both static and dynamic aeroelastic issues. We have applied this knowledge for aircraft primes, research organisations and under collaborative research programmes.

We have extensive experience in the development of complex and innovative models to address specific issues as well as addressing more common fluid structure interactions problems.

AeroTex have also been involved in linking the aeroelastics and loads through to structural optimisation software.

Capabilities

Analysis Types

• Aero-structural interaction – staff at AeroTex have been involved in coupling aerodynamic and structural analysis codes.
  • Aerodynamic codes – Fluent, Newpan (both Steady and Unsteady coupling)
  • Structural Codes – Nastran and Modal models
• Aeroelastics analysis – production of flutter clearance documentation for an aircraft prime.
• Smart rotor blade analysis – coupling in Nastran including interaction with blade mounted control surfaces.
• Dynamic response analysis – based on unsteady aerodynamic data gathered during testing.
• Aeroservoelastics – analysis of system gains and design of notch filters.
• Non-linear aeroelastics analysis – use of bifurcation and numerical continuation to analyse both continuous and discrete non-linear systems

Advice

AeroTex has extensive experience in aeroelastic analysis and can advise customers on the best approaches to be taken to meet certification requirements.

• Requirements for certification.
• Stages in certification.
• Experience leading and conducting stiffness testing.
• Experience leading and conducting Ground Vibration Tests.
• Ground engineer during first flight and flutter envelope expansion trials.

Case Studies

Flutter Clearance for Rear Empennage

An aircraft prime requested that AeroTex provide Flutter support as part of clearance of their product for flight.

• Produced advice document describing analysis approach to be used during certification.
• Analysed Rear Empennage including variation in attachment stiffness to account for system non-linearity.
• Provided advice to address concerns expressed by Certification Authorities.

Quantification of Vibration under Aerodynamic Loading

A customer was developing a new version of their wind tunnel support system and requested that AeroTex support them in de-risking their developments.

• Production of trials and instrumentation plan.
• Instrument test model and support structure.
• Produce finite element model of support structure.
• Conduct hammer rap tests on test model.
• Use sub-structuring to link modal model to FE model of the support structure.
• Application of pressure data to hybrid model to recreate dynamic response and validate the modelling approach.
• Join new support model to the modal model of the wing to assess vibration response.

Rotorblade Aeroelastic Analysis

Under a research programme AeroTex were requested to conduct flutter analysis of a smart rotor blade.

• Using structural requirements data AeroTex produced a beam representation of the rotor blade.
• A separate model was produced of the control surface.
• Stripwise aerodynamic models were produced including scaling to account for the variation in speed along the blade.
• Models coupled to produce a flutter envelope.