Issues in Optimization Jaroslaw sobieski NASA Langley Research Center Hampton Virginia NASA Langley research Center A LaRC/SMCIACMB Copyright NASA, Jaroslaw Sobieski, 2003
Issues in Optimization Jaroslaw Sobieski NASA Langley Research Center Hampton Virginia NASA Langley Research Center LaRC/SMC/ACMB Copyright NASA, Jaroslaw Sobieski, 2003
How to know whether optimization is needed
How to know whether optimization is needed
How to recognize that the problem at hand needs optimization General rule of the thumb there must be at least two opposing trends as functions of a design variable X f1 Analysis 12 f2 f2 X
How to recognize that the problem at hand needs optimization. • General Rule of the Thumb: there must be at least two opposing trends as functions of a design variable Analysis x f1 f1 f2 f2 f1 f2 x
Power line cable tout cable slack cable h Length(h) mIn · Given A(h ·| ce load Volume(b)A self-Weight small h/span small tout h slack
Power Line Cable tout cable slack cable h Length(h) • Given: A(h) • Ice load Volume(h) • self-weight small • h/span small A L V min tout h slack
Wing Thin-Walled BoX Lift Top cover panels are compressed .Buckling stress f(t/b)2 thickness t Wing box weight Cover weight min Rib total weight many rew ribs ribs
Wing Thin-Walled Box Lift •Top cover panels are compressed b thickness t •Buckling stress = f(t/b)2 many b Rib total weight min few Cover weight Wing box weight ribs ribs