MODIFIED SEMI-ANALYTICAL SENSITIVITY ANALYSIS AND ITS ERROR CORRECTION TECHNIQUES

Modified semi-analytical sensitivity analysis algorithm and its error correction term method are presented, where the sensitivity analysis terms and the error correction term can be separated. The method can facilitates program implementation and the accuracy of the method won’t be influenced by perturbation step length and number of elements. Firstly, a modified semi-analytical sensitivity analysis technique with its error correction term is presented for static displacement, which is based on global structure equations of the sensitivity analysis, and its program implementations are provided. Then, the modified method is implemented on other analysis tasks including natural frequency and linear buckling analysis. Consequently, the error correction terms of both beam elements and shell elements are derived. Then, the specific deducing process of error correction terms concerning beam and shell elements is described. Next, the modified method is verified by typical finite element models with beam and shell elements. The results highlight the applicability of the modified method to various analysis types mentioned above, and the accuracy is not influenced by the number of elements and perturbation step length. Since sensitivity analysis parts and error correction term can be computed respectively, the error correction term can becomputed independently and added directly to the results of sensitivity analysis, which can make full use of existing sensitivity analysis programming. This modified method can help complex engineering structural design. Especially, compared to the original semi-analytical sensitivity analysis and error correction methods, the computational efficiency of the modified method is enhanced with respect to shape optimization design variables or shape combined with size optimization, which can provide new ideas for sensitivity analysis and its program implementation.