Solutions in Aerospace Industry

The cost of design, production and operation, and time-to-market in general are of increasing importance in aerospace projects. Like other industries, future success will depend to a large extend in the ability to leverage the use simulation technologies and integrate the often complex processes of design, modeling, analysis, manufacturing and test.

The integration of finite element analysis with structural testing is a key area to look for synergy when optimizing processes. FEMtools can be used to increase the productivity of analysts and test engineers in many ways. Following is just an non-exhaustive overview of tasks in aerospace engineering where FEMtools can be applied:

Target mode selection - The results from baseline finite element analysis can be used for target mode selection.
Selection of optimal locations for sensors, actuators and suspension -
Identifying and exporting maser DOFs for system matrices reduction
Construction and export of a test model - Using this information, the FE model can be reduced to construct a test model which makes geometrical mapping of the FE and test model trivial.
Test-verification of FE models - Predictions of resonance frequencies and mode shapes can be validated against experimental results using commonly used criteria like Modal Assurance Criterion (MAC) and cross-orthogonality. The diagonal and off-diagonal values of these matrices are used in standard acceptance criteria.
Identification of damping
Structural dynamic modification
Substructuring
Sensitivity analysis
Component model updating
Assembled structure model updating
Multi-model updating
Force identification

Application Cases

Study of a Rotating Helicopter Blade

One of the most important analysis to determine the dynamic behavior of a rotating part is the determination of the Campbell diagram, that shows the variation of natural frequencies versus angular velocities. The basic idea is to validate the FE model of the blade using FEMtools and then to investigate the difference between the Campbell diagram obtained with the non updated model and the updated one. The model geometry and experimental results are provided by the NASA Technical Memorandum 4760.
(POLITECNICO DI TORINO)

References

J. Guggenberger, MI 17 Fire Firefighting Helicopter Boom - Validation and Updating of the Analytical Models. Presented at the 2002 NAFEMS Conference on Validation of FEM Analysis, November 13-14, Wiesbaden, Germany.
Download (PDF, 500 KB)

M. Mergeay, J.-S. Servaye, E. Dascotte, Integration of NVH Testing: A Case Study on a Spatial Structure. Presented at the 2002 International Seminar on Modal Analysis (ISMA), September 16-18, 2002, Leuven, Belgium.
Download (PDF, 755 KB)

E. Dascotte, A. Schoenrock, Validation and Updating of an Aeroengine Finite Element Model based on Static Stiffness Testing. Presented at the 2nd MSC Aerospace Conference, June 7-11, 1999, Long Beach, CA, USA.
Download (PDF, 233 KB)

For more, information on the topics and cases that are presented, contact us at info@femtools.com.