Fatigue analysis and remaining useful life

WHAT IS IT?
This turnkey consultancy service is an evolution of the hydroelastic strong coupling within seakeeping application Tdyn SeaFEM and FEA application Tdyn RamSeries, together with tools like OpenFAST, providing clients with advanced engineering calculation software, as well as the technical knowledge and expertise to address these highly complex technical problems.

Using these powerful tools, CIMNE Naval, UPM-CEHINAV, and COMPASS Ingeniería y Sistemas have developed a methodology based on Reduced Order Modeling (ROM), enabling the efficient calculation of stress, fatigue damage results and remaining useful life, accounting for all coupled effects (mooring loads, wind, currents, and waves) in the time domain.

WHAT IS ITS ADDED VALUE?
The methodology offered by this service revolutionizes the design, optimisation and verification process:

1. Drastically reduces computational times for structural dynamic analysis, which is typically a bottleneck, allowing the calculation of the large number of load cases required to analyze fatigue damage.
2. Solves the challenge of integrated load analysis for Floating Offshore Wind Turbines (FOWT).
3. Helps reduce costs (calculation times and result volumes) by providing near real-time insights into the design, enabling continuous optimization.
4. Can be used during the structural design phase to evaluate strength, fatigue damage, and remaining useful life, and can even be incorporated as a digital twin of the platform.
5. The analysis methodology complies with current regulatory codes from major Classification Societies, such as:
   • BV NI 572 DT R02 E, January 2019 – “Classification and Certification of Offshore Floating Wind Turbines”
   • BV NI 611 DT R01 E, November 2020 – “Guidelines for the Fatigue Assessment of Ships and Offshore Units”
   • DNV-RP-C203, September 2019 – “Fatigue Design of Offshore Steel Structures”
   • DNV-ST-0119, June 2021 – “Floating Wind Turbine Structures.”

WHO CAN BENEFIT FROM THIS SERVICE?
Any company or client looking to optimize, improve, verify, certify, or even start from scratch any floating platform design (FOWT or others).

Moreover, the entire supply chain involved can benefit from this methodology: designers, manufacturers, certification companies, and more.

WHAT DOES THIS SERVICE INCLUDE?

• Generation of FEA models from customer’s design data (CAD/drawings).
• Generation of seakeeping models for generation of the Modal RAOs’ points.
• Linearization of the customer’s mooring system design, together with the wind loads provided by the customer.
• Modal analysis (“wet” modes).
• Creation of the escenarios corresponding to the Fatigue Design Load Cases defined by the customer.
• Calculation of the stresses, strains and fatigue damage in the points defined by the customer (“hot spots”).
• Detailed reporting of the different results: customized graphical output with multiple contour fill map options, and graphs.
• Assessment of the results and advice on possible structural optimization actions and service life extension.

LINKS

Projects and Customers

• KOWL (developers and collaborators)

Technological Partners

• CEHINAV (developers and collaborators)
• CIMNE Naval (developers and collaborators)

Theoretical foundations

• High Fidelity Hydroelastic Analysis Using Modal Matrix Reduction
• Fatigue Damage calculation based on hydroelastic model