A Generalized Solution on the Static Characteristics of Short Hydrodynamic Journal Bearings Using Harmonic Components

A theoretical analysis has been done to investigate the static performance of short hydrodynamic journal bearings with a generalized film thickness expression by a sum of Fourier series equation. The hydrodynamic film thickness was written into a summation of an infinite harmonic component of trigonometric function. Reynolds equation with short bearing theory is solved for steady-state operations. In this paper, the steady-state analysis of the generalized hydrodynamic bearing has been done and compared with some typical journal bearings with respect to their harmonic components of film thickness, pressure distribution and load capacity. The relationship between the k-th order harmonic component of the film thickness H-0,H-k and the static pressure component P-0,P-k was established. It was found that the value of P-0,(k) is directly determined not only by the k-th order harmonic component H-0,(k) but also the (k-1)-th order component P-0,P-k-1 indirectly produced by the previous harmonic component H-0,(k-1).This new investigation method can used to improve the performance of hydrodynamic journal bearings for shape optimization of hydrodynamic journal bearings.