Multi-Field Coupling Dynamics Modeling of Aerostatic Spindle

Area of Science:

• Mechanical Engineering
• Precision Engineering
• Dynamics and Control

Background:

• Aerostatic spindles in ultra-precision machine tools exhibit complex multi-field coupling dynamics.
• Understanding these dynamics is crucial for optimizing spindle performance and structure.
• Numerical investigations offer a cost-effective approach to analyzing dynamic characteristics.

Purpose of the Study:

• To develop a comprehensive multi-field coupling dynamics model for aerostatic spindles.
• To investigate the dynamic characteristics and behaviors under working conditions.
• To provide insights for improving the design and performance of aerostatic spindles.

Main Methods:

• A 5-degree-of-freedom (5-DOF) dynamics model was proposed, incorporating air film, spindle shaft, and motor interactions.
• The restoring force method was used to handle time-varying air film forces.
• Transient Reynolds equations for journal and thrust bearings were solved using the Alternating Direction Implicit (ADI) and Thomas methods.

Main Results:

• Transient air film pressure was obtained, demonstrating the influence of spindle shaft tilt motion.
• The motion trajectory of the spindle shaft was simulated, revealing varying stability under different external forces.
• The developed dynamics model effectively simulated the multi-field coupling behavior under external forces.

Conclusions:

• The proposed multi-field coupling dynamics model accurately captures the behavior of aerostatic spindles.
• The model is valuable for understanding dynamic characteristics and guiding structural improvements.
• This research contributes to the advancement of ultra-precision machine tool technology.