AbstractThe prediction of cavitation in journal bearings is one of the current challenges in the field of computational fluid dynamics. Hydrodynamic journal bearings are used in a wide range of technical and industrial applications because they provide low friction and minimal wear. A failure of the bearing system during operation can be caused by suction cavitation. Cavitation describes the phase change from liquid to vapour of a fluid caused by a decrease in pressure below the fluid's vapour pressure at an approximately constant temperature. The implosion of vapour cavities adjacent to the surface of the bearing liner stresses the liner material which in turn can lead to material erosion. The particular case of suction cavitation can be observed, if the bearing is operated under high loads resulting in high eccentricity between shaft and bushing combined with a significant increase in gap width. Suchlike operating conditions are not uncommon for internal combustion engines with a power of 0.1 to 1.0 MW per cylinder. As a result of the transient shaft displacement a suction effect builds up within in the lubricating film accompanied with a strong pressure gradient. Due to the fluid dynamics of the lubricant film flow at the given pressure gradient, the liquid can only equalize the void caused by the shaft displacement until the fluid pressure reaches the vapor pressure and then vapor is generated. The vapor forms a three‐dimensional layer across the lubricating film. Whereas, current flow calculations for hydrodynamic journal bearings are carried out by means of 2D methods which are limited to analyze the three‐dimensional and transient flow in those areas of the journal bearing where cavitation occurs. This work presents the application of a transient, 3D numerical simulation of the two‐phase fluid flow in a journal bearing under conditions of cavitation. The numerical simulations were performed using the code OpenFOAM, which is based on the finite volume method and uses time‐dependent three‐dimensional, incompressible Navier‐Stokes equations. The study on hand discusses the influence of minimal film thickness and displacement velocity vs. the structure of the vapour distribution. The numerical results include images of complex three‐dimensional flow structures and vapor distributions inside the lubricating film.