The output of this Phase I will be several lighter weight ACV 1.1 potential candidates, these include components within the land and marine propulsion systems (drive shafts and propeller), hull shapes (bow vane and stern/trim flaps) as well as doors, hatches, inlet grill, exhaust ducts and grills. These components will take advantage of the ideal properties that composite has to offer: lightweight, high specific strength, inherent corrosions resistance, limited constraints in shape and contour. To minimize un-sprung weight and provide the requisite strength/stiffness, in the propulsion system we anticipate the use of composite drive shafts for the wheels and propellers. For the propeller blades and shrouds we anticipate using Sandwiching a low-density, lightweight foam core material between thin face sheets can dramatically increase a laminate's stiffness to match a metallic part with decrease in weight. A sandwich structure is also cost-effective because the relatively low-cost core replaces the materials that would be used to produce a thick laminate. PEI will also investigate using hydrophobic coatings with nano additives on composite shrouds, bow and stern planes surfaces to improve abrasion and impact damage resistance as well as reduce drag. Significant drag reduction has been measured in turbulent flows over hydrophobic surfaces.
Benefit: The benefits of PEI SBIR Phase I is the transition of advanced composites and nano-coatings technologies to achieve significant weight savings and improved water and land performance for the Amphibious Combat Vehicle (ACV) 1.1. Specifically, PEI designs and development of drivetrain components such as composite drive shafts and props as well as evaluating the use of light weight composites for the propeller assemblies, shrouds, doors, exhaust components, bow vanes and stern flap will increase ACV performance. The weight savings brought about through the use of composites, approximately 70% vs. steel and 30% vs. aluminum, will yield a reduction in vehicle weight as well as an increase in operational performance. This includes increased fuel efficiency, mobility and buoyancy. Composite structures are also able to absorb and dissipate vibrations (and other harmonics), are inherently insulative (to noise and heat), and are much safer than metals when they do fail. Finally, composites are intrinsically resistant to corrosion which makes them ideal for use in the AAV operational environment. The combination of reduced weight, longer life, and corrosion resistance enhances the maintainability and affordability.
Keywords: Drive Shafts, Drive Shafts, Modeling, Light weight, High Strength, Materials, Composites, Propellers, molding