In service health monitoring for Rotorcraft structures
Host institution
Politecnico di Milano (Italy)
Supervisors
Co-tutoring institution
Delft University of Technology (The Netherlands)
Start date
Strictly before end of May 2017
Duration
36 months + 12 month
Gross salary
39.820,00 € per year
Work location
Mainly Milano (Italy) and Delft (The Netherlands)
Objective
Sensor networks based on optical fibers (OF) have a great application potential to develop lightweight monitoring systems in modern aerospace structures since they can provide local and distributed measures of strain and temperature, being immune from electromagnetic disturbance and with several possibility of integration in the structures. Technology is mature to be implemented in real-world structures, but successful exploitation requires a multi-disciplinary approach to design feasible and effective Health and Usage Monitoring Systems (HUMS) that combine both the possibility of reconstruction of thermo-mechanical load conditions and of detecting local outliers originated by damage development.
The objective of the research is to develop and assess approaches to reconstruct the nominal strain fields during the variation of thermo-mechanical loads conditions and to predict the outliers induced by damage development at hot spots originated by the release of the stress state induced during the technological processes (curing, co-curing and secondary bonding), by the alteration of the load paths and the modification of thermal response due to damages. In particular, research will be focused on damage at the interfaces between composite layers and/or composite and metallic parts in hybrid structures.
A first part of the activity will be aimed at developing and assessing numerical approaches for a reliable prediction of strain states induced by technological process, in-service operation and damage development. Such phase will include manufacturing of sensorized representative coupons that will be monitored in all the phases of the process and during the mechanical tests carried out to promote progressive damage development at different temperatures.
A second part of the activity will consider a virtual prototype of a composite or composite/metallic hybrid component and will refine, apply and assess fast methods based on FEM and inverse FEM analyses to reconstruct nominal strain fields during varying thermo-mechanical load conditions by using a relatively dense sensor network. By combining such Usage Monitoring Systems with the numerical approaches developed and validated in the first phase, a HUMS will be designed for strain field detection and damage identification in specific structural hot spots.
Research profile
This researcher will be working at the Politecnico di Milano together with Technical of Delft to obtain a double doctorate award. The ESR will develop skills in composite FEM modeling, design and technological implementation of OF-based sensor networks, development of algorithms for data elaboration and statistical analysis.
Research field
• Rotorcraft
• Non-linear FEM analyses
• Process, Health and Usage Monitoring of Composite structures
• Composite materials
• Material science
Requirements
• Degree in aerospace, mechanical, or material engineering
• Experience with Nonlinear-FEM
• Ability to model composite material
• Ability to perform structural laboratory tests
• Background in structural engineering
Type of contract
The successful ESR applicant will be offered a 3-year full-time funded contract by Politecnico di Milano. The fourth year will be funded on a separate project details will be discussed during the selection interview.
Additional Eligibility criteria
English language (IELTS overall score 6.5; no sub-test less than 6.0)
