DYNAMIC RESPONSE OF A DISCRETE MULTI-LAYERED CYLINDER DUE TO THERMAL SHOCK

A discrete multi-layered cylindrical shell (DMC) consists of a thin inner cylindrical shell and helically cross-winding flat steel ribbons, and is of advantages of convenient fabrication and low costs. The prediction of its stress is crucial for developing design code and operating procedures to the use of DMC. Thusly, the dynamic thermo-elastic responses of a DMC subjected to rapid arbitrary heating are studied. Based on the axisymmetric plane strain assumption, the general solutions for dynamic displacement equilibrium equations of both inner shell and outer ribbon layer are decomposed into two parts, i.e., a thermo-elastic part satisfying inhomogeneous stress boundary conditions and a dynamic part meeting homogeneous stress boundary conditions together with initial conditions. The thermo-elastic part is determined by linearity method, and the dynamic part is worked out by means of finite Hankel transform and Laplace transform. By using radial displacement continuity, a second kind Volterra integral equation about the pressure at the interface with respect to time is derived, which can be solved by interpolation functions. The thermo-elastic solution of a DMC is compared with the solution of a monobloc cylindrical shell. Numerical results are presented and analyzed with consideration of different major influential factors, such as winding-angle and material parameters.