Static Characteristics of Hybrid Water-Lubricated Herringbone Groove Journal Bearing

The hydrodynamic herringbone groove journal bearing (HGJB) performs exceptionallywell at high speeds but is limited by a low load-carrying capacity, largely due to the lubri-cation characteristics of water. To address this issue, a hybrid water-lubricated HGJB isproposed in this study. A lubrication model for the high-speed hybrid water-lubricatedHGJB is developed, taking into account turbulence, thermal effects, and tilt. A comparativeanalysis of the static characteristics is conducted between the hybrid HGJB and both thehydrodynamic HGJB and the hybrid plain journal bearing (PJB). The results show thatthe proposed hybrid water-lubricated HGJB offers significantly greater load-carryingcapacity than the conventional hydrodynamic HGJB, particularly during start-up or atlow speeds. For example, when the bearing operates at 1000 rpm with an eccentricityratio of 0.5, the load-carrying capacity of the water-lubricated hybrid HGJB under asupply pressure of 1.6 MPa reaches 650 N, compared to just 261 N for the water-lubricatedhydrodynamic HGJB. Additionally, the hybrid water-lubricated HGJB demonstrates ahigherflowrate and lower temperature rise than the traditional hybrid PJB, thanks to theimproved pumping effect of the herringbone grooves at high speeds.