Accurate design sensitivities for closed-filled structures application to plastic bottles

Many efficient structural optimization algorithms require gradient informat ion. Semi-Analytical (SA) design sensitivities are rattler popular, as they combine ease of implementation with computational efficiency. For closed-f illed structures also the effects of internal pressure changes and solubili ty of the gas in the fluid may be important. Typical examples for which the se aspects are relevant can be found in packaging, e.g. edible-oil bottles. The present paper focuses on design sensitivities for such closed-filled s tructures. The design sensitivities are based on a refined SA formulation f or the structure, whereas the contribution related to its contents is evalu ated analytically.