Characteristics of micro-gas journal bearings based on kinetic theory

According to Poiseuille and Couette flow rate correctors, Q ˜ p ( D , α 1 , α 2 ) and Q ˜ C ( D , α 1 , α 2 ) , the modified molecular gas lubrication (MMGL) equation is applied for the analysis of micro-gas journal bearings. The effects of gas rarefaction are considered for arbitrary inverse Knudsen numbers (D) and non-symmetric accommodation coefficients (AC) conditions (α1≠α2). The combined effects of Q ˜ p ( D , α 1 , α 2 ) and Q ˜ C ( D , α 1 , α 2 ) on the performance of micro-gas journal bearings are firstly discussed. The results show that the surface property (AC) of moving surface affects the bearing performance more significantly than that of stationary surface does. The load carrying capacity increases as the AC of moving surface increases or the inverse Knudsen number increases.