Adaptive step-size numerical vibration correlation technique for buckling prediction of thin-walled shells under axial compression and thermal loads

Purpose The purpose of this paper is to propose a numerical prediction method of buckling loads for shell structures under axial compression and thermal loads based on vibration correlation technique (VCT). Design/methodology/approach VCT is a non-destructive test method, and the numerical realization of its experimental process can become a promising buckling load prediction method, namely numerical VCT (NVCT). First, the derivation of the VCT formula for thin-walled structures under combined axial compression and thermal loads is presented. Then, on the basis of typical NVCT, an adaptive step-size NVCT (AS-NVCT) calculation scheme based on an adaptive increment control strategy is proposed. Finally, according to the independence of repeated frequency analysis, a concurrent computing framework of AS-NVCT is established to improve efficiency. Findings Four analytical examples and one optimization example for imperfect conical-cylindrical shells are carried out. The buckling prediction results for AS-NVCT agree well with the test results, and the efficiency is significantly higher than that of typical numerical buckling methods. Originality/value The derivation of the VCT formula for thin-walled shells provides a theoretical basis for NVCT. The adaptive incremental control strategy realizes the adaptive adjustment of the loading step size and the maximum applied load of NVCT with Python script, thus establishing AS-NVCT.

Automated summary

This paper proposes a numerical prediction method for buckling loads in shell structures under axial compression and thermal loads based on vibration correlation technique (VCT). The method, named numerical VCT (NVCT), is a non-destructive test method that can be realized numerically. The paper presents the derivation of the VCT formula for thin-walled structures and introduces an adaptive step-size NVCT (AS-NVCT) calculation scheme based on an adaptive increment control strategy. The findings demonstrate that AS-NVCT achieves accurate buckling prediction results and higher efficiency compared to typical numerical buckling methods.