Periodic Reporting for period 2 - CoPropel (Composite material technology for next-generation Marine Vessel Propellers.)
Reporting period: 2023-12-01 to 2025-05-31
Beyond limitations in vibration, electric signature, and weight, conventional metal propellers also suffer from high production costs and complex maintenance, resulting in extended delays for replacement parts, ships being out of commission, and high operational expenses for shipyards. CoPropel introduces a holistic approach by developing composite marine propellers, offering superior corrosion resistance, significant weight reduction, tailored material properties, and reduced noise.
CoPropel has set forth an ambitious set of objectives, which encompass (i) designing a large-scale composite marine propeller utilizing the inherent anisotropy of composite materials, (ii) optimising the process for the manufacture of the composite propeller, (iii) developing an embedded structural health monitoring system, and (iv) validating the composite propeller's performance. The project also aims to assist in formulating new guidelines for composite marine propellers, communicate and disseminate the outcomes, and define a comprehensive roll-out strategy and business plan.
Ultimately, CoPropel is set to significantly boost European competitiveness in shipbuilding. The project will overcome current limitations in the maritime industry by introducing advanced composite materials and smart elements for real-time monitoring. This innovation fosters a new EU market for marine propulsion, leveraging existing European expertise in composites from sectors like aeronautics, automotive, and wind energy. Furthermore, CoPropel will advance beyond traditional design and production, crucially enhancing vessel safety through novel inspection, maintenance, and long-term damage monitoring. This holistic approach will significantly reduce the environmental footprint of the maritime industry, directly aligning with key EU policies on Gas Emissions (Directive 2012/33/EU) and Underwater Noise (Directive 2008/56/EU).
CoPropel has set forth an ambitious set of objectives, which encompass (i) designing a large-scale composite marine propeller utilizing the inherent anisotropy of composite materials, (ii) optimising the process for the manufacture of the composite propeller, (iii) developing an embedded structural health monitoring system, and (iv) validating the composite propeller's performance. The project also aims to assist in formulating new guidelines for composite marine propellers, communicate and disseminate the outcomes, and define a comprehensive roll-out strategy and business plan.
Ultimately, CoPropel is set to significantly boost European competitiveness in shipbuilding. The project will overcome current limitations in the maritime industry by introducing advanced composite materials and smart elements for real-time monitoring. This innovation fosters a new EU market for marine propulsion, leveraging existing European expertise in composites from sectors like aeronautics, automotive, and wind energy. Furthermore, CoPropel will advance beyond traditional design and production, crucially enhancing vessel safety through novel inspection, maintenance, and long-term damage monitoring. This holistic approach will significantly reduce the environmental footprint of the maritime industry, directly aligning with key EU policies on Gas Emissions (Directive 2012/33/EU) and Underwater Noise (Directive 2008/56/EU).
Within CoPropel two marine composite propellers incorporating an embedded Structural Health Monitoring (SHM) system were designed, manufactured and validated through testing.
The design was optimised using the concept of a flexible propeller .The orientation of the carbon fibres was tailored in order for the propeller to attain the shape of the metal propeller under the load at its operating point. On the other hand, the shape of the propeller at zero load is different to match the ideal pitch at other operating points . The manufacturing process incorporated certification steps, including blade balancing, vibration testing, and non-destructive inspection. The process was further optimized by numerical simulations for Resin Transfer Moulding (RTM) tooling and injection, alongside a Process Monitoring Optimization and Control (PMOC) system that enabled real-time monitoring. Two distinct SHM technologies were developed and deployed on CoPropel: (i) a distributed fiber optic sensing system and (ii) a strain gauge system, enabling wireless data transmission. A Life Cycle Assessment (LCA) was also performed to assess the composite propeller’s environmental impact compared to metal.
Through small scale static, ground vibration and hydrodynamic testing the manufacturing process, design assumptions, and numerical simulations were successfully validated. Additionally, the tests provided valuable insights on the performance of the composite propeller and enabled correlation of SHM data with theoretical models. Full-scale propeller design and manufacturing adhered to BV NI663 certification requirements, including material characterization, fatigue studies and prototype testing for the assembly solution. The composite propeller was mounted on “Le Palais” boat and a sea trials campaign in accordance with BV guidance was performed, testing the composite and the reference metal propeller for comparative analysis. The sea trials campaign was successful, and data analysis highlighted the advantages of composite materials for marine propellers.
The design was optimised using the concept of a flexible propeller .The orientation of the carbon fibres was tailored in order for the propeller to attain the shape of the metal propeller under the load at its operating point. On the other hand, the shape of the propeller at zero load is different to match the ideal pitch at other operating points . The manufacturing process incorporated certification steps, including blade balancing, vibration testing, and non-destructive inspection. The process was further optimized by numerical simulations for Resin Transfer Moulding (RTM) tooling and injection, alongside a Process Monitoring Optimization and Control (PMOC) system that enabled real-time monitoring. Two distinct SHM technologies were developed and deployed on CoPropel: (i) a distributed fiber optic sensing system and (ii) a strain gauge system, enabling wireless data transmission. A Life Cycle Assessment (LCA) was also performed to assess the composite propeller’s environmental impact compared to metal.
Through small scale static, ground vibration and hydrodynamic testing the manufacturing process, design assumptions, and numerical simulations were successfully validated. Additionally, the tests provided valuable insights on the performance of the composite propeller and enabled correlation of SHM data with theoretical models. Full-scale propeller design and manufacturing adhered to BV NI663 certification requirements, including material characterization, fatigue studies and prototype testing for the assembly solution. The composite propeller was mounted on “Le Palais” boat and a sea trials campaign in accordance with BV guidance was performed, testing the composite and the reference metal propeller for comparative analysis. The sea trials campaign was successful, and data analysis highlighted the advantages of composite materials for marine propellers.
The CoPropel project successfully developed a deformable composite propeller with variable pitch, eliminating complex mechanical control. A robust, manufacturing process for composite blades on a metal hub was established, incorporating Process Monitoring & Optimization Control (PMOC) and Structural Health Monitoring (SHM) systems. The design and manufacturing process for composite propellers is no longer a prototype but an industrial product. Small-scale and large-scale trials validated the design, performance and ease of assembly (50% lighter). Sea trials demonstrated significant power gains on the shaft line (up to 19%) thanks to the variable pitch of the blades. Fuel savings of circa 4% were measured. There was no discernible difference in the boat's manoeuvrability between the composite and metal propellers. Finally, BV updated the guidance note NI663, establishing new certification criteria for composite marine propellers.
These advancements drive innovation in the Marine Industry and pave the way for more energy-efficient vessels, reduced operational costs and enhanced safety. The exploitation of the full potential of CoPropel innovations and their expansion in the market depends on targeted future research to address the key points identified in CoPropel. New propeller designs that initiate from the properties of the composite to optimise the shape of the propeller in conjunction with refined hydrodynamic numerical simulations that take into account the hull and cavitation are needed. The design of the assembly solution can be improved by reducing the thickness of the hub to achieve a shape similar to a metal propeller. It will also be necessary to consider the impact resistance and erosion of the composite blade coating to ensure the reliability of the product. To guarantee fuel savings and reduced noise emissions, it will be essential to consider the existing shaft line (engine, shaft balancing). Monitoring and inspection require PMOC system upgrades for unified software, X-ray inspection for accurate porosity detection, and miniaturized SHM systems providing wireless communication and user-friendly software. Ultimately, full BV certification is paramount for commercialization.
These advancements drive innovation in the Marine Industry and pave the way for more energy-efficient vessels, reduced operational costs and enhanced safety. The exploitation of the full potential of CoPropel innovations and their expansion in the market depends on targeted future research to address the key points identified in CoPropel. New propeller designs that initiate from the properties of the composite to optimise the shape of the propeller in conjunction with refined hydrodynamic numerical simulations that take into account the hull and cavitation are needed. The design of the assembly solution can be improved by reducing the thickness of the hub to achieve a shape similar to a metal propeller. It will also be necessary to consider the impact resistance and erosion of the composite blade coating to ensure the reliability of the product. To guarantee fuel savings and reduced noise emissions, it will be essential to consider the existing shaft line (engine, shaft balancing). Monitoring and inspection require PMOC system upgrades for unified software, X-ray inspection for accurate porosity detection, and miniaturized SHM systems providing wireless communication and user-friendly software. Ultimately, full BV certification is paramount for commercialization.