On the calculation of structural stiffness of compliant bump foil bearing

A simplified formula was developed to calculate the local structural stiffness of each bump of the bump foil with the consideration of frictions between bump foil and its contact surfaces, and the influences of different parameters on the structural stiffness were analyzed. Results show that the values of local structural stiffness of bump foils decrease from the fix-end to the free-end, rather than being uniform; the structural stiffness of bump foil bearing increases with the accretion of bump elastic modulus, thickness and non-fixed bump height, fraction coefficients of contacting surfaces while increases with the decrease of bump half length and pitch. The influence of bump pitch is more prominence than other parameters.