Optimization design of porous aerostatic bearing for full aperture rapid planar polishing machine

This paper discusses about how to optimize design of an aerostatic bearing. In order to achieve the objective, there are four necessary qualifications: high load capacity, high stiffness, low flow rate and uniformly pressure distribution, those make an aerostatic bearing optimized. The finite difference method is employed to obtain the numerical solution of the pressure distribution between the surface of aerostatic bearing and worktable. The performance is determined by the pressure distribution of aerostatic bearing. Furthermore, this study proposed an integrated optimal approach that is HTGA/Gray. Comparing with many kinds of optimal theories finds out the most suitable parameters of an aerostatic bearing. Finally, the experimental results for the load capacities and flow rates clearly indicate that the proposed aerostatic bearing can enhance ability effectively.

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An evaluation system of the eccentric orbit of shaft with aerostatic bearing in the microscale

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650117709151 ◽

2017 ◽

Vol 232 (2) ◽

pp. 155-165

Author(s):

Dongju Chen ◽

Jihong Han ◽

Lihua Dong ◽

Jinwei Fan ◽

Chenhui An

Keyword(s):

Evaluation System ◽

Optimization Design ◽

Dynamic Stiffness ◽

Test System ◽

Displacement Sensor ◽

Aerostatic Bearing ◽

Evaluation Standard ◽

Shaft System ◽

Control Equation ◽

Orbit Model

In order to improve the machining precision of the aerostatic bearing, an eccentric rotor orbit model considering the microscale effects is established. A flow factor Q embodying the effects in the microscale is introduced into the fluid control equation, the dynamic stiffness, and damping coefficients of bearing are calculated considering the microscale effects. According to the actual working condition of the shaft, the modal analysis in both cases (with and without the microscale effects) is performed. And with the modal information, the dynamic orbit in both states (with and without the microscale effects) is described by the deduced orbit model of the shaft system. Finally, experiments of the frequency by LMS vibration test system and shaft orbit by displacement sensor are measured, and the results indicate that the simulated results considering the microscale effects are more similar with the actual experimental one, which provides a guideline and evaluation standard for further optimization design and precision control of the shaft system.

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Investigating the influences of pressure-equalizing grooves on characteristics of aerostatic bearings based on CFD

Industrial Lubrication and Tribology ◽

10.1108/ilt-11-2018-0411 ◽

2019 ◽

Vol 71 (7) ◽

pp. 853-860

Author(s):

Ruzhong Yan ◽

Liaoyuan Wang ◽

Shengze Wang

Keyword(s):

Optimization Design ◽

Load Capacity ◽

Static Characteristic ◽

Aerostatic Bearing ◽

Content Type ◽

Distribution Form ◽

Pressure Distributions ◽

Static Performance ◽

Ultra Precision ◽

Aerostatic Bearings

Purpose The purpose of this study is to reveal the influence law of pressure-equalizing grooves on aerostatic bearings and improve the static performance of bearings by optimizing the distribution form of grooves. Design/methodology/approach In view of two kinds of common restrictor distribution forms on the thrust surface, the linear and the rectangular, six kinds of pressure-equalizing groove schemes were proposed – the line-shape, the extended-shape, the S-shape, the oblong-shape, the X-shape and the reticular-shape. Based on the analysis of lubrication theory of the orifice-type aerostatic bearing, the numerical simulations of different bearings were carried out. The pressure distributions and static characteristic curves of different bearings were obtained. Findings The study reveals that the adoption of the pressure-equalizing grooves can substantially improve the load capacity and static stiffness of the bearing and make the bearing maintain a uniform stress, which enhances operating accuracy and life of the bearing. The superior function of the reticular-shape groove is highlighted. Originality/value The research results can effectively guide the optimization design of aerostatic bearings and provide a crucial technical reference for application of ultra-precision aerostatic supporting system.

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Multi-Factor Analysis and Combination Optimization Design of Subway Train Travel Speed

Resilience and Sustainable Transportation Systems ◽

10.1061/9780784482902.037 ◽

2020 ◽

Author(s):

Zihuan Deng ◽

Hua Hu ◽

Xiulian Liu

Keyword(s):

Factor Analysis ◽

Optimization Design ◽

Travel Speed ◽

Combination Optimization ◽

Subway Train

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Optimal design of a high homogeneous and small-size shim coil for atomic spin gyroscope based on 0-1 linear programming

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209319 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 165-172

Author(s):

Dongge Deng ◽

Mingzhi Zhu ◽

Qiang Shu ◽

Baoxu Wang ◽

Fei Yang

Keyword(s):

Linear Programming ◽

Power Consumption ◽

Low Power ◽

Optimization Design ◽

Structural Parameters ◽

Axial Position ◽

Low Power Consumption ◽

Optimal Method ◽

Atomic Spin ◽

Shim Coil

It is necessary to develop a high homogeneous, low power consumption, high frequency and small-size shim coil for high precision and low-cost atomic spin gyroscope (ASG). To provide the shim coil, a multi-objective optimization design method is proposed. All structural parameters including the wire diameter are optimized. In addition to the homogeneity, the size of optimized coil, especially the axial position and winding number, is restricted to develop the small-size shim coil with low power consumption. The 0-1 linear programming is adopted in the optimal model to conveniently describe winding distributions. The branch and bound algorithm is used to solve this model. Theoretical optimization results show that the homogeneity of the optimized shim coil is several orders of magnitudes better than the same-size solenoid. A simulation experiment is also conducted. Experimental results show that optimization results are verified, and power consumption of the optimized coil is about half of the solenoid when providing the same uniform magnetic field. This indicates that the proposed optimal method is feasible to develop shim coil for ASG.

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