Military vehicles including the HMMWV (High Mobility Multipurpose Wheeled Vehicle, alsocalled the Humvee) have been required to add anti-ballistic armor to shield against IED's(Improvised Explosive Devices) and other ballistics. This weight addition was not included inthe vehicles' original design and as a result many vehicles are fatiguing much quicker andbreaking down in fields of combat. In order to combat this weight increase, our team hasinvestigated replacing steel components in the vehicle chassis with advanced composite/steelhybrid designs. Baseline stiffness and strength analysis were first established with currentdesigns/materials. The hybrid design optimizations were conducted utilizing the Genesissoftware package from Vanderplaats R & D . Weight reductions of 30% were achieved withsame stiffness hybrid designs of a subassembly (reductions up to 65% resulted on a per partbasis). To analyze the static strength and fatigue life Alpha Star's Genoa software package wasused. Static strength increased by 20% while fatigue life increased by 75%.The advantages of utilizing HPC (High-Performance Computing) for these analyses was alsoinvestigated. In the past, vehicle component redesigns and optimizations have been performedon a system or subsystem level. General assumptions of the boundary conditions on the outerenvelope of the systems have to be made in order to obtain convergent solutions. Theseassumptions could be by-passed by performing whole vehicle modeling. Working with the OSC(Ohio Supercomputer Center) our team measured calculation time for static durability analysesof various models of complexity and number of elements. It was determined that for small tomedium sized models, which would include component and subsystem analyses, the advantageof using HPC was minimal. However, for much larger models, which would include entirevehicles, a 38% reduction in run time was achieved compared to what could be modeled withstate of the art workstations. This advantage was even greater for complex fatigue modeling,resulting in a run time reduction of 52%.
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