System model correction method oriented to multipoint excited vibration test

Abstract

The invention discloses a system model correction method oriented to a multipoint excited vibration test. The system model correction method oriented to the multipoint excited vibration test comprises the steps that Young moduli of all units are selected as parameters to be corrected, a modal reduction method is combined to perform model correction; the model correction based on sensitivity analysis combines with the modal reduction method to perform correction. The system model correction method performs model correction based on the modal reduction method, the calculation time can be greatly shortened, and the calculation efficiency is improved. A sensitivity analysis technology is introduced to finite element dynamic simulation of a multipoint excited vibration testing system, and the purpose of making a simulation result and a testing result consistent is achieved. A testing effect can be predicted through the corrected multipoint excited vibration test system model before test implementation and can directly serve as the basis and foundation of a multipoint exciting test design and control method.

Description

technical field [0001] The invention belongs to the technical field of mechanical engineering finite element simulation, and in particular relates to a system model correction method for multi-point excitation vibration tests. Background technique [0002] The multi-point excitation vibration test system refers to the vibration test that uses multiple shaking tables to excite the specimen along a single or multiple axial directions at a time. Model correction means that when establishing a finite element model and conducting test inspections, sometimes it is found that the model has systematic deviations, indicating that the model is defective. At this time, it is necessary to add some items to the model or adjust some parameter values. Accurately reflect the dynamic characteristics of the actual structure, so as to predict the test effect, guide the test design and control method. In engineering applications, with the continuous development of industry, the requirements fo...

AI Technical Summary

Problems solved by technology

There are mainly the following technical problems in the test modeling: ① The problem of modal omission. Due to the selection of the test excitation method during the test process, some modals may not be excited, resulting in modal omission and other phenomena; ② The problem of the degree of freedom of the test mode is complete , due to the function and number of sensors, the number of degrees of freedom in the test is limited, and the information of the rotational degree of freedom cannot be measured; ③The simulation of boundary conditions is distorted, and a completely free state does not exist in reality, and the fixed state is difficult to be measured. Simulation etc.

In addition, test modeling requires trial production of prototypes, purchase of expensive test instruments, etc., which objectively increases test costs

[0003] In summary, the existing test modeling has the defects of modal omission, complete degree of freedom of test mode, and simulation distortion of boundary conditions.

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