The distribution of air film pressure fields was solved by using computational fluid dynamics software，and the simulation method proposed was validated by comparison of the calculation data of loading force with published results.The effects of the number of grooves,the spiral angle,the groove depth,the ratio of groove length and width on the loading force were investigated.The results indicate that a high pressure area is observed as the gas flowing through the groove is compressed,which eventually forms the loading force.The loading force is increased gradually and tends to a constant value with the number of grooves increased,and there is an optimum value for the spiral angle,the groove depth,the ratio of groove length and width to make the loading force the maximum.