Modal analysis of an aerostatic spindle system for ultra-precision machine tools at different spin speeds

Peng Chen,Jianguo Ding,Yu Chang,Hong Yang,Hui Zhuang,Qidi Zhong

doi:10.1177/1687814018798528

Peng Chen, Jianguo Ding + Show 4 more

Open Access

https://doi.org/10.1177/1687814018798528

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Abstract

The dynamic properties of aerostatic spindle systems vary with the spindle speed and have a significant impact on the processing quality of ultra-precision machine tools. In this article, using the ICEM CFD, the structured grid model of a large-span scale gas film is built under the condition in which the ratio of the spindle gas film length to the gas film thickness is 13,100. Integral calculation model of spindle and thrust is established and CEL expressions are compiled based on dynamic meshing technique to acquire trajectory of aerostatic spindle system. The degree of freedom method is used to obtain flow field of spindle system. Considering the spindle system as an elastomer, the influence of rotational speed on natural frequencies is studied under the flow field boundary. The results indicate that the former four-order natural frequencies of the aerostatic spindle system will clearly increase as the rotational speed increases. The increase in the fifth- to seventh-order natural frequencies is small, and the eighth-order natural frequency is almost invariable. The flow field has little influence on the mode shapes of the aerostatic spindle system. The former four-order natural frequencies of spindle system decrease considering rotation effects. Rotational speed and rotation effects mainly impact the tilting motion natural frequencies of spindle and thrust.

Highlights

Aerostatic spindles have several advantages, such as high precision, low friction, low temperature rising, and long service life, compared to traditional spindles.[1]
Because the modal analysis of aerostatic spindle system is an important part of the spindle dynamic characteristics analysis and the basis of the
It can be seen that when the rotation effects are not considered and considering the flow field boundary, the spindle system rotational speed has a considerable influence on the natural frequencies corresponding to the tilting modes of the spindle and thrust

Summary

Introduction

Aerostatic spindles have several advantages, such as high precision, low friction, low temperature rising, and long service life, compared to traditional spindles.[1]. Considering the spindle system as an elastomer, the influence of rotational speed, rotation effects, and flow field on the natural frequencies and modes of the aerostatic spindle system is studied.

Results

Conclusion