3D-DEGENERATED THERMAL SHELL ELEMENTANALYSIS IN COMPOSITE LAMINATES

According to the geomet ric form of a shell element , geomet ric formulations of the shell element are deduced. This paper supposes that temperature has quadratic variation through layers of the shell element , and givesthe expression of temperature functions in given boundary conditions. In this paper , the orthot ropic feature of material property is considered ; heat conductivity can be t ransformed from material coordinates into element coordinatesand then the formulations of thermal analysis are deduced. Finite element formulations are established using 3D-degenerated shell element and then thermal shell formulations are gotten. Thus this method can change 3D problemsinto 2D problems. Then a program is designed to test this theory. It not only has the same precision with isoparamet ric element , but also improves the efficiency of analysis. It also can save memory of computer and running time.The numerical result s are compared with ANSYS result s and are satisfactory.