Why Geared Engines?
Aeronautic market evolution is moving to geared engines since they generate promising architectures to reduce fuel consumption compared to turbofan engines. The Power transmission Gear Boxes (PGB) design is critical to increase the high power density at high operative speeds, and their design needs to increase the robustness taking into account manufacturing tolerances under hyperstatic conditions.
Experimental Design of Experiments
The OPTIMIZE project aims to realise a dedicated experimental Design of Experiments (DOE) to evaluate the effects on gear efficiency. The study employs a full factorial DOE with 4 X variables at 2 levels each, enabling a systematic analysis of how key geometric and manufacturing parameters influence power reduction gearbox performance.
Variables Under Study
| Variable | Symbol | Description |
|---|---|---|
| Pressure angle | — | Angle between the tooth profile and a radial line at the pitch point |
| Total cumulative pitch deviation | Fp | Maximum cumulative error in tooth spacing around the gear |
| Total profile deviation | Fα | Deviation of the actual tooth profile from the ideal involute form |
| Total helix deviation | Fβ | Deviation of the tooth flank helix from its nominal geometry |
Each variable is tested at two levels within a full factorial experimental matrix, allowing the project team to isolate main effects and interactions that govern gear efficiency under representative operating conditions.
Project Consortium
The experimental campaign is defined and executed by a consortium coordinated by DMP (Desarrollos Mecánicos y de Precisión, S.L.), with IK4-TEKNIKER as research alliance partner and Avio Aero as topic manager. Detailed partner roles and responsibilities are available on the Partners page.
A dedicated experimental Design of Experiments approach is central to the OPTIMIZE project's mission of advancing power reduction gearbox technology. By systematically varying key parameters such as gear geometry, lubrication conditions, and operating speeds, the project can isolate and quantify each factor's influence on overall gear efficiency. This methodical testing framework allows researchers to identify optimal design configurations that balance high power density with mechanical robustness. The hyperstatic conditions inherent in modern geared engine architectures demand precise understanding of how manufacturing tolerances affect real-world performance. Through carefully structured experiments, the project generates actionable data that informs more resilient gearbox designs capable of maintaining efficiency across demanding operational envelopes.
Geared engine architectures represent a significant evolutionary step in aeronautic propulsion, offering tangible reductions in fuel consumption compared to traditional turbofan designs. The power transmission gearbox sits at the heart of this innovation, operating under extreme conditions of speed and load while maintaining strict weight constraints. Increasing power density at high operative speeds requires innovative solutions to thermal management, lubrication, and structural integrity. The OPTIMIZE project addresses these challenges by developing design methodologies that account for the complex interactions between gear tooth contact patterns, housing deflections, and bearing preloads. This holistic approach ensures that next-generation gearboxes deliver both performance gains and the reliability required for aviation applications.