Homogenized elastic stiffness of fin layer in tube-fin structures (Verification for bending loading)

Abstract

The authors recently developed a homogenization method for fin layers in tube-fin structures composed of flat tubes and wavy fins. In this paper, the resulting, homogenized elastic stiffnesses of fin layers with designed and real shapes are applied to finite element (FE) analysis of tube-fin layered plates subjected to bending. By comparing the fin-homogenized and full-scale FE analysis results, the homogenized elastic stiffnesses of fin layers are shown to be valid even under bending although the homogenized method is of first-order. Bending experiments of tube-fin layered plates are moreover performed to examine the homogenized elastic stiffnesses of fin layers. It is shown that the bending strains are predicted well if the real shapes of outer and inner fins are considered in the fin-homogenized FE analysis. It is also shown that the Bernoulli-Euler assumption is not satisfied in the homogenized outer fin layers in the analysis.

Keywords

• tube-fin structure
• finete element analysis
• homogenization
• elastic stiffness
• bending