Sailing Through the Waves of Competitive Racing with Fine Marine

Competitive sailing requires a good grasp of environmental dynamics, advanced technology, and refined strategies to achieve optimum performance. The America’s Cup and the Vendée Globe stand as paragons of yacht racing, where every detail is scrutinized for maximum efficiency. In the America’s Cup, for instance, teams are prohibited from conducting physical testing of their boats during certain periods, which places an even greater emphasis on simulation and computational methods.

This blog post examines the transformative impact of Fine Marine's advanced computational fluid dynamics (CFD) tools on race design simulations, highlighting how this technology enables precise analysis and validation of critical fluid dynamics phenomena, ultimately enhancing performance and efficiency in marine racing design.

Challenges of High-Stakes Racing

Competitions such as the America’s Cup and Vendée Globe inspire teams and sailors to explore new frontiers in technology. The America’s Cup features intense, short races requiring rapid decision-making and precise execution under varying weather conditions. Teams rely on CFD simulations to analyze weather forecasts and fine-tune designs that can adapt during the 15-minute sprints.

Meanwhile, the Vendée Globe is a grueling three-month race in which energy management and reliability are key. Design approaches diverge between using versatile boats that handle various conditions or specialized designs that excel in specific scenarios. Here, comprehensive performance mapping is crucial to ensure minimal adjustments, enabling long-term efficiency.

Fine Marine at the Core of Design Innovation

CFD is crucial for enhancing sailing performance through three primary applications. It assists in determining operational conditions by evaluating elements such as the sailing environment (whether inshore or offshore), race duration, and types of propulsion. Additionally, CFD examines the interplay between technical limitations like structural restrictions or class regulations while facilitating the optimization of performance across different sailing situations. Performance analyses investigate how the boat behaves under various wind and sea conditions, helping sailors enhance their competitive advantage.

About Fine Marine

Fine Marine is a cutting-edge CFD tool purpose-built for marine applications. Drawing on deep industry expertise, it tackles the complexities of sailing design with precision and efficiency. Acting as a virtual towing tank, it solves the Reynolds-averaged Navier-Stokes equations for incompressible flows and employs volume of fluid (VOF) methods to accurately model free surface modeling.

With full six-degrees-of-freedom (6DOF) body motion simulation and specialized modules, Fine Marine delivers unmatched insights into vessel behavior. This empowers designers to optimize performance under real-world operating conditions – whether racing or refining hull shapes for minimal drag and maximum stability.

Importance of Meshing for Marine Simulations

High-quality meshing is the foundation of effective CFD simulations. To capture key aerodynamic and hydrodynamic features, meshing must balance accurate geometry representation with manageable computational requirements. Techniques like the overset mesh method in Fine Marine allow for relative motion between boat and background meshes, ensuring high resolution even for complex geometries like asymmetrical hydrofoils.

Using several Overset domains for controlling rudder rotation in a simulation

The innovative "sock mesh" approach (curved domain that follows the shape of a foil with a structured mesh) further enhances simulation accuracy, reducing issues such as diamond cells and allowing for efficient mesh adaptation as the hydrofoil moves. These advancements ensure robust results, critical for designing high-performance, condition-adaptive boats.

Hydrodynamic Simulations and Solver Techniques

Hydrodynamic simulations rely on solver configurations to calculate resistance forces and optimize the boat's motions—including pitch, heel, leeway, and roll—under varying conditions. Advanced numerical methods, including quasi-static approaches and convergence acceleration, enhance solver efficiency, ensuring simulations remain seamless and increasingly realistic. By replicating complex environmental interactions and forces, Fine Marine provides invaluable guidance in designing competitive, versatile boats.

Photo Courtesy: Finot Conq

Wave generation is central to modeling realistic sea states in CFD simulations. Fine Marine supports both regular and irregular wave modeling, with advanced options for user-specific spectra. By incorporating theoretical models, the software seamlessly validates a wide spectrum of waves.

For sea-keeping simulations, adaptive grid refinement (AGR) dynamically adjusts the mesh to reduce computational overhead while capturing critical physical and numerical interactions. This enables accurate modeling of free-surface dynamics and improves design assessments in challenging conditions.

Automation for Enhanced Productivity

The C-Wizard, an innovative automation tool within Fine Marine, accelerates the setup process by preparing complete CFD projects in seconds. It integrates mesh configurations, simulation setups, and advanced guidelines to ensure accuracy and consistency. Offering features like velocity prediction program (VPP) integration, the tool supports robust design iterations, empowering teams to refine geometry variations effectively.

Addressing Critical Phenomena in Race Design

Using Fine Marine, three critical phenomena in race design can be effectively addressed.

Ventilation

Ventilation, a sudden loss of lift when air moves along lifting profiles near the free surface, poses significant risks. Predicting and mitigating this phenomenon is vital to ensure stability and performance. By analyzing pressure and mass fraction parameters, Fine Marine helps refine profiles for optimal operational ranges.

Cavitation

Cavitation, caused by vaporization due to pressure drops on lifting surfaces, can hinder performance and damage materials. Fine Marine accurately models cavitation onset, providing insights into profile limits and mitigating potential race-day setbacks. Additionally, interactions with laminar-turbulent transitions are addressed, further improving race designs.

Fluid-Structure Interaction

Fluid-structure interaction (FSI) phenomena, including fluttering and dynamic deformations, are critical for efficient sailing. Fine Marine facilitates dynamic analysis, identifying structural vulnerabilities and enhancing material resilience. Moreover, designs can be optimized for both specific performance points and unsteady conditions.

Setting Sail with Fine Marine

Fine Marine's CFD capabilities have reshaped the competitive sailing landscape, from the intense sprints of the America’s Cup to the unwavering endurance demanded by the Vendée Globe. With advanced solvers, mesh technologies, and automation tools, Fine Marine empowers designers and teams alike to push performance boundaries while navigating the unpredictable nature of marine racing. For those at the forefront of competitive sailing, leveraging CFD tools is the key to unlocking precision, adaptability, and success on the global stage.

Watch the on-demand webinar Transforming Sailing Yacht Performance with America's Cup-Level CFD for more information on how Fine Marine is transforming high-stakes marine racing.