Studies of modal characteristics aimed at comprehensive validation of a calculation model by the example of a modern vehicle body

Introduction (problem statement and relevance). The article presents calculation and experimental studies of modal characteristics of a motor vehicle body required for comprehensive validation of a finite element model (FEM) according to the criterion of reliability of modal shapes, coordinate criteria of modal reliability and the criterion of reliability by frequency response. Within the study, the papers related to calculation model validation in terms of modal characteristics were analyzed, theoretical calculations of the analytical modal analysis were given, a body FEM was developed, body modal characteristics were studied, experimental studies of characteristics of metals, shock absorbing and acoustic materials used in the calculation model were conducted, and also experimental studies of frequencies and mode of the body natural oscillations were performed. The calculation model validation was performed. The algorithm for the calculation models validation was developed.

The purpose of the study is to study vehicle body modal characteristics in order to validate the calculation model.

Methodology and research methods. Study of vehicle body modal characteristics. Calculation model validation. Check of experimental study results in terms of frequencies and modes of natural oscillations.

Scientific novelty and results. The result of the studies is the developed and validated FEM of a modern vehicle body. The developed algorithm that allows validating the calculation model by the criteria of reliability of modal shapes, coordinate criteria of modal reliability and the criterion of reliability by frequency response. The scientific novelty consists in comprehensive FEM validation based on the vehicle body modal characteristics study. For the first time, the materials characteristics obtained from the experimental studies are used in the course of research and a validation algorithm for calculation models has been developed.

Practical significance. The validation algorithm is developed according to which comprehensive FEM validation is performed by the example of a modern vehicle body with the use of modern software packages allowing studying modal characteristics. The research results can be used in scientific, research, educational institutions and manufacturing enterprises specializing in development and production of vehicle bodies for comprehensive FEM validation.

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