Engaging structural-acoustic simulations in multi-discipline design.

Abstract

In order to be effective and maximize the weight and cost savings, designing for noise and vibration attributes must be performed in parallel when designing a complex system for other disciplines (i.e., durability, crashworthiness, etc.). The system characteristics influence the performance in all the different attributes. Challenges arise when designing a system for improving mutually competing objectives, satisfying constraints from multiple engineering disciplines, and determining a single set of values for the vehicle characteristics. This presentation discusses an approach that conducts optimization analysis for a complex system by coordinating operations and exchange of data and information through a network of optimizations. A rotorcraft application is analyzed for structural-acoustic and crashworthiness. The hybrid finite element analysis (hybrid FEA) comprises the simulation method used for the structural-acoustic simulation. It combines conventional FEA with energy FEA for modeling the response of a system comprised by stiff, load bearing members, and flexible panels. The LS-DYNA solver is used for the crash-landing simulations. The weight of the gear box foundation is optimized while simultaneous improvements are pursued through parallel driven optimizations that address the input power into the system from gearbox excitation and the dynamic stresses encountered in the gearbox foundation from crash landing.