Air bearing center cross gap of neutron stress spectrometer sample table support system

Abstract

A support system is the main load-bearing component of sample table for neutron stress spectrometer, and air bearing is an important element of a support system. The neutron stress spectrometer sample table was introduced, and the scheme for air bearing combination was selected. To study the performance of air bearing center cross gap, finite element models (FEMs) were established based on air motion and Reynolds equations, effects of air supply pressure, and gap parameters on the overturning moment and bearing capacity of air bearing center cross gap were analyzed. Results indicate that the width, depth, and height differences of the marble floor gap played important roles in the performance of the air bearing. When gap width is lesser than 1 mm and gap depth is lower than 0.4 mm, bearing capacity and overturning moment would vary rapidly with the variation of the width and depth. A gap height difference results in the bearing capacity dropping rapidly. The FEM results agree well with experimental results. Further, findings of the study could guide the design of the support system and marble floor.

Key words： neutron stress spectrometer; sample table; support system; air bearing; center cross gap; simulation; experiment

Acknowledgements

This study is supported by the National Natural Science Foundation of China (Grant Nos. 51405520 and 51327902), and the Autonomous Research Topic Fund of State Key Laboratory of High Performance Complex Manufacturing (Grant No. 2014bcxjj06).

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