Aero Structural Coupling

DESIGNING THE IDEAL FLYING SHAPE

Sail Shape: Using our own 3D design program, actual boat specifications and our extensive database of boat and sail types, the size and geometry of the sail are defined and a mold shape created. Sophisticated editing tools allow for the highest levels of accuracy and refinement.

Aerodynamic Analysis: Using a virtual prototype of the sail shape and computational fluid dynamic (CFD) calculations, designers compute and visualize aerodynamic forces, wind angles and velocities, and the distribution of air pressure on each side of the sail. The resulting images and data help predict performance.

Structural Analysis and Fiber Mapping: Using finite element analysis (FEA), Quantum designers visualize where the sail bends and twists and the distribution of stress and strain within the membrane. The virtual sail is attached to a rig model that takes into account the properties of the running and standing rigging and longitudinal and transverse stiffness. Data gained through in-house materials testing is added to the equation to evaluate the effects of different fiber types, amounts, and placement leading to the development of a custom fiber map.

The integration of 3D modeling, CFD and FEA (Fluid Structures Interaction) allows designers to assess and refine varying elements of the sail design leading ultimately to the optimal size, shape, structure, fiber type, and fiber layout of the finished product. Quantum’s expertise in using these tools is particularly valuable when applied to large sailing yachts, which present unique challenges due to variable weight placement and heavy loads.

INFRARED HEAT

To create the laminate, fibers are strung on the base film in a custom pattern according to the design specifications. During application, excess glue is stripped from the fibers to avoid saturation, minimize brittleness, and to achieve the highest strength to weight ratio. After the top layer of film is in place, a vacuum bagging process is used to “shrink wrap” the film around the fibers. The layers are then fused using infrared heat. Quantum’s carbon infrared emitter system is a quick and efficient heat source that is easily controllable to ensure that just the right amount of heat is applied during the laminating process depending upon the type and amount of materials being used in your sail. To fabricate modern composites, infrared heat or UV radiation is used because they quickly and homogeneously heat or cure them. It also transfers heat directly and precisely without having to contact the laminate and damage the components, and can be used in the vacuum conditions Quantum uses during lamination.

Intense Pressure

Quantum uses two-part, thermo-set adhesives, which require high heat and pressure for lamination compared to simple thermo-molded adhesives. Several tons of pressure are applied to the vacuum-bagged laminate to ensure the adhesive is evenly spread. This proprietary process squeezes the adhesive down to the thinnest possible layer and ensures the highest possible adhesive to fiber ratio.

Cross-Linked Molecular Structure

The thermo-set adhesives used in Fusion M™ sails undergo a transformation at the molecular level during lamination. The high heat and intense pressure induce polymerization—the creation of a cross linked molecular structure as the two part adhesive “kicks.” The result is a laminate with 4-5 times the sheer strength of a traditional hot-melt (thermo-molded) method.

Post-Cured Shaping

Unlike single-step lamination and shaping methods used by other sailmakers, sections of a Quantum® Fusion M™ sail are completely cured before the shaping process begins. This process eliminates the effects of shrinkage and distortion under the heat of the lamination process and guarantees repeatability. The carefully optimized aerodynamic shape of a Quantum® sail is reliably provided to each and every client, every time.