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For many complicated design challenges, including those involving sophisticated computer simulations and modeling, it is vital to have a systematic and efficient method for exploring available design spaces and finding optimal or near-optimal design solutions. A simple method for relatively quick and straight-forward sampling and subsequent evaluation of design spaces is proposed. No special optimization software or expertise in optimization is required.

In Statistical Energy Analysis and Energy Flow Analysis models of connected beam systems, it is necessary to determine the power reflection and transmission coefficients of the structural joints. The use of a spectral element formulation to estimate the joint coefficients for any number of rigidly connected beams oriented at any angle in all three dimensions is presented. The longitudinal, transverse, and torsional wave types are modeled and assembled into beam elements. A force is applied to the system and the magnitudes of the transmitted and reflected waves are identified and used to calculate the joint's power reflection and transmission coefficients. Examples are presented to illustrate the procedure.

Statistical energy analysis (SEA) is a validated tool for vibro-acoustic modeling of larger systems such as air- and spacecraft, ships, and automobile bodies. In this paper, we report on the application of SEA to model the noise and vibration output of a vee-configuration automotive engine above 1000 Hertz. This approach may complement boundary element methods, which are time consuming to use and can only be applied up to one or two kilohertz. In a feasibility study, experimental data is used to specify power inputs and damping losses, as well as to validate the model. The study shows that SEA can be used to model the vibrational behavior of the engine block at high frequencies that are unattainable with deterministic methods. This result may apply to other structures such as transmissions, pumps, and superchargers.