Objectives, Constraints, Design 16888 ES077 Variables Define objectives J Define Design variables x Define Constraints and Bounds g, h Determine important fixed parameters p Influence matrix influence o no 9 influence model relationships Massachusetts Institute of Technology -Prof de Weck and Prof. Willcox
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Mlesd Physics Based Modeling 50. 9 Start with governing equations Continuum Mechanics for physical systems Introduce Boundary conditions Introduce Initial conditions EXternal forcing functions Discretize system Massachusetts Institute of Technology -Prof de Weck and Prof. Willcox
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Mles Governing equations 16888 ES077 Continuum (Structural) Mechanics o, T MIstress s=It o. t tensor F2 F strain -equilibrium Equations 2F =0 -Constitutive equations o, Ee d x-dx compatibility equations e, dr Massachusetts Institute of Technology - Prof de Weck and Prof Willcox
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Mlesd Example: Finite Element Model E5. Mx+cxtkx=F Geometry Mass and Connectivity Inertia Matrix Material Properties Deflections Boundary Stress. Strain Conditions Natural Loads Frequencies Mode shapes Assumptions Discretization Time as variable Static Steady state Transient Massachusetts Institute of Technology- Prof de Weck and Prof Willcox
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Mles Empirical Modeling 16888 ES077 Derive a model, not from physics and first principles, but from observation, i.e. data Usually leads to low order models Only valid under similar operating conditions Many cost models are of this nature Massachusetts Institute of Technology - Prof de Weck and Prof Willcox
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