SAGE project, included in Clean Sky research project aimed at the demonstration of engines and technologies to reduce the fuel consumption and therefore reducing CO2 emissions in order to fulfil the European Aviation environmental objectives for 2020 of decrease 50% of CO2 emissions.
WELDMINDT project was focused on giving solutions for the inspection of welded components with limited access in Open Rotor Engines. This led to a cost reduction in Open Rotor Engines manufacturing and maintenance by reducing the time of inspections, facilitating the market entry of this more effective and cleaner engines.
Hence, indirectly the project results will have an important impact in environment, as well as the obvious industrial and technological impacts. Project’s main technical objectives were:
- Integrate in a single system shearography, Infrared Thermography and Ultrasonic inspection
- Use laser as a single excitation source for the inspection system
- Advance in the knowledge of pseudo-real defects generation in advanced materials with different welding processes
- Develop an automatic inspection system based on industrial robotics applications
- Develop a FEM based model valid for fast piece simulation
- Develop an “automatic” defect detection and sizing estimation software
As conclusion, directly or indirectly the following impacts were expected:
- The combination of multiple NDT techniques added to the use of advanced signal processing will increase the defect detection rate and size precision more than 20%,
- Change the aero-engine inspection time concept: from minutes-hours (or even days in maintenance) to seconds,
- Reduce simulation time more than 90% maintaining the precision,
- By means of flexible fibres and other techniques as mirrors gain access/vision to currently inaccessible parts,
- 30% fuel efficiency improvement.
During WELDMINDT project, the development as well as the capability of three novel non-destructive testing techniques (Active Thermography, Shearography and Laser Ultrasonics) was analysed. At the beginning of the project representative samples were manufactured which consisted of welds containing defects that resemble real conditions. The initial developments were assisted by Finite Element Modelling in order to better understand the underlying physical phenomena. As a result of extensive laboratory work for finding the best excitation and detection system some relevant conclusions were drawn.
Laser Ultrasonics was found to be a very promising technique for surface defect detection, although its maturity is not as high as in the other techniques. With respect to Shearography, a novel procedure was suggested that allows inspecting thin plates from the back side (opposite side of defects location). This is really advantageous for hidden areas inspection since the miniaturization of the system is not required. Finally, an automated inspection system was build based on Active Thermography as a proof of concept of the benefits of this technique for the project goals. This was performed in a relevant environment and over representative samples (part of a turbine). In addition, a miniaturization concept was suggested and proved at a lab scale.