Residual stress sensitivity analysis using a complex variable finite element method

• Published in: International journal of mechanical sciences Vol. 133; pp. 112 - 120
• Main Authors: Fielder, Randal, Montoya, Arturo, Millwater, Harry, Golden, Patrick
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2017
• Subjects: Autofrettage; Complex taylor series expansion method; Complex variable finite element method; Residual stress; Sensitivity analysis; Autofrettage; Complex variable finite element method; Complex taylor series expansion method; Sensitivity analysis; Residual stress
• ISSN: 0020-7403; 1879-2162
• DOI: 10.1016/j.ijmecsci.2017.08.035

•ZFEM was used to calculate partial derivatives of the residual stress field.•Sensitivities are calculated with respect to material parameters and applied load.•Nonlinear ZFEM obtains sensitivities throughout the loading/unloading cycle.•ZFEM results were shown to be in excellent agreement with analytical solutions.•ZFEM can obtain sensitivities while simulating the manufacturing processes. [Display omitted] The application of the complex variable finite element method, ZFEM, to structures containing residual stresses is detailed. A thick-walled sphere model is subjected to an autofrettage process to induce the residual stress field and solved using ZFEM. The stress results from ZFEM are compared to an analytical solution and to standard finite element results. Sensitivities are calculated with respect to material parameters and to the applied load. The ZFEM partial derivative results are shown to provide excellent accuracy when compared with numerical derivatives of the analytical solution and finite differencing of standard finite element solutions. Hence, ZFEM provides an effective step-size independent method to compute shape, material and loading sensitivities for structures subjected to residual stresses.