Riding the Wave
with Cloud 9 Surf Foils

Cloud9 Surf Foils

Cloud 9 Surf Foils designs and manufactures performance hydrofoils. Founded by a group of passionate foilers and athletes, Cloud 9 Surf Foils is all about pushing the boundaries of hydrofoil design. Based in California and distributed all over the world, they create foils that take performance and fun to the next level for intermediate to expert foilers.

Paul Langlois-Meurinne is the composites and manufacturing engineer at Cloud 9 Surf Foils. He holds a Master of Science in Yacht and High-Performance Craft Design (University of Southampton UK) and another in Mechanical Engineering (France) and has been designing high-performance hydrofoils since 2018, blending his passion for hydrodynamic performance with composite structure optimization. He also brings experience from competitive sailing, kitesurfing, and wing foiling, which helps him refine designs that truly meet the needs of high-level athletes.

Simulation at Cloud 9

At Cloud 9, Paul and the team are a group of foilers driven by a passion for innovation. They use hydrodynamic simulations in nearly every aspect of the design process, which lets them refine every detail—right down to the angle of attack profile. A typical workflow includes CFD for hydrodynamic performance and FEA for structural integrity, ensuring that their foils are as stiff, durable, and high-performance as possible. Foils are exposed to dynamic forces on the waves and need to be designed with analysis as early as possible in the development process.

The team has focused attention on the aggressive carving characteristics of the F Series wing products and wanted to combine its forward swept (FS) trailing edge design, which allowed it to be highly responsive with the speed, pump, and glide of the latest generation of high aspect wings that are out on the market today. The new FS High Aspect foils offer a perfect blend of performance and speed.

SimScale Powers Innovation

SimScale has been a key enabler in the team’s ability to innovate quickly and efficiently. By leveraging CFD, Paul is able to fine-tune the hydrodynamic profile and optimize the angle of attack (AoA) with incredible precision, sometimes down to 1/10th of a degree. This ensures that the foils perform optimally in a wide range of conditions, from downwind stand-up paddle (SUP) foiling to wing foiling at high speeds.

On the structural side, the team relies heavily on FEA to determine the best composite layup for each part of the hydrofoil. Using a proprietary algorithm, they link the results of these FEA simulations in SimScale to real-world material properties, allowing them to create foils that are not only stiff and strong but also lightweight and durable. The ability to run both hydrodynamic and structural simulations in parallel means they can iterate quickly on design concepts, validating new ideas without needing to prototype every variation physically.

SimScale’s cloud-based platform has further reduced overhead by eliminating the need for expensive hardware and licensing. It allows the team to focus resources on design and performance rather than infrastructure, ultimately giving a competitive edge and enabling better products to market faster.