Sensitivity Numerical Calculation Method Based on Response Signal

Abstract

The invention provides a sensitivity numerical calculation method based on a response signal, which comprises the steps of constructing a velocity frequency response function matrix, obtaining a firstm-order modal frequency, and adding a stiffness perturbation term from the first node of the structure; obtaining the perturbed velocity frequency response function by substituting the velocity frequency response function information into the matrix correction formula; obtaining the sensitivity of structural modal frequency to stiffness by extracting the frequency information of the structure;changing the position of the stiffness perturbation point according to the node order, obtaining the sensitivity of the whole structural modal frequency to stiffness and drawing the sensitivity curve. The method is characterized by firstly obtaining the velocity frequency response function information of the structure through the finite element calculation, when the structural stiffness changes, using the matrix transformation formula to obtain the velocity response information after perturbation only by numerical calculation of the initial velocity frequency response function without the finiteelement recalculation, so that the method simplifies the calculation efficiency and is more convenient. The fast calculation method of frequency sensitivity to stiffness is realized based on the velocity frequency response function, so that the method has practical engineering significance.

Description

technical field [0001] The invention relates to a sensitivity analysis method, in particular to a numerical calculation method of structural sensitivity. Background technique [0002] Sensitivity analysis is a method to evaluate the rate of change of structural response characteristics due to changes in design variables or parameters. The study of structural system sensitivity is a very special field, and it is one of the main research directions in the fields of computational mechanics and structural engineering. [0003] In practical applications, the sensitivity analysis of structures plays an important role in structure optimization, reliability evaluation, and parameter identification. According to the strategy, the methods can be divided into discrete methods and variational methods. Traditional sensitivity analysis methods generally need to perform finite element calculations again under perturbation, especially when the structure is large and the number of finite el...

AI Technical Summary

Problems solved by technology

The traditional sensitivity analysis method generally needs to recalculate the finite element calculation under perturbation, especially when the structure is large and the number of finite elements is large, the calculation amount is large and the efficiency is low

Some working conditions need to measure the speed, so that the sensitivity analysis such as stiffness parameters can be performed based on the speed frequency response function information. If the traditional sensitivity calculation efficiency is low, it has become a practical engineering problem that needs to be solved urgently.

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