TY - JOUR

T1 - High performance 3D-analysis of thermo-mechanically loaded composite structures

AU - Rolfes, R.

AU - Noack, J.

AU - Taeschner, M.

PY - 2000/1/11

Y1 - 2000/1/11

N2 - This paper considers the analysis of composite structures, simultaneously loaded by mechanical and thermal loads, as often found in aerospace applications. Typically a thermal analysis providing the temperature field must precede the stress analysis, which has to account for thermal as well as for additional mechanical loads. Presently, thermal analyses are mostly carried out by finite difference methods or by 3D finite elements, whereas the stress analysis is usually performed by the use of shell elements. Thus, the temperature field has to be transferred from a finite difference or 3D finite element model to a shell finite element model. This process often requires lots of manual user interaction and can get very time consuming. The paper suggests an integrated analysis process which uses a shell finite element model throughout. Thermal lamination theories and related finite elements developed by the first author are used for the 3D thermal analysis. This leads to a reduction of the computing time by two orders of magnitude as compared to 3D finite elements whereas the accuracy of the results is nearly unaffected. The stress analysis is carried out using the same geometry model but with different mesh density. Interpolation between the different meshes can be accomplished automatically since both discretizations are defined on the same geometry. Standard shell elements based on the First order shear deformation theory (FSDT) provide the three in-plane stress components. A novel postprocessing scheme is adopted for determining all transverse stress components from the in-plane stresses and the temperature field. The postprocessing methodology is based on the extended 2D-method which utilizes the material law for transverse shear and the 3D equilibrium conditions. It is computationally very efficient and can be applied in conjunction with any standard finite element package. The interaction of thermal and stress analysis is demonstrated by the example of a composite wing box for a future large airliner.

AB - This paper considers the analysis of composite structures, simultaneously loaded by mechanical and thermal loads, as often found in aerospace applications. Typically a thermal analysis providing the temperature field must precede the stress analysis, which has to account for thermal as well as for additional mechanical loads. Presently, thermal analyses are mostly carried out by finite difference methods or by 3D finite elements, whereas the stress analysis is usually performed by the use of shell elements. Thus, the temperature field has to be transferred from a finite difference or 3D finite element model to a shell finite element model. This process often requires lots of manual user interaction and can get very time consuming. The paper suggests an integrated analysis process which uses a shell finite element model throughout. Thermal lamination theories and related finite elements developed by the first author are used for the 3D thermal analysis. This leads to a reduction of the computing time by two orders of magnitude as compared to 3D finite elements whereas the accuracy of the results is nearly unaffected. The stress analysis is carried out using the same geometry model but with different mesh density. Interpolation between the different meshes can be accomplished automatically since both discretizations are defined on the same geometry. Standard shell elements based on the First order shear deformation theory (FSDT) provide the three in-plane stress components. A novel postprocessing scheme is adopted for determining all transverse stress components from the in-plane stresses and the temperature field. The postprocessing methodology is based on the extended 2D-method which utilizes the material law for transverse shear and the 3D equilibrium conditions. It is computationally very efficient and can be applied in conjunction with any standard finite element package. The interaction of thermal and stress analysis is demonstrated by the example of a composite wing box for a future large airliner.

KW - Finite elements

KW - Thermal analysis

KW - Thermo-mechanical bahaviour

KW - Transverse stresses

KW - Wing box

UR - http://www.scopus.com/inward/record.url?scp=0039763616&partnerID=8YFLogxK

U2 - 10.1016/S0263-8223(99)00101-4

DO - 10.1016/S0263-8223(99)00101-4

M3 - Article

AN - SCOPUS:0039763616

VL - 46

SP - 367

EP - 379

JO - Composite structures

JF - Composite structures

SN - 0263-8223

IS - 4

ER -