Research On The Dynamic Performance Of Water-Lubricated Herringbone Groove Thrust Bearings

Support bearings are required to meet rigorous demands due to the substantial axial loads present in power equipment,including ship main engines,compressors,and power generation equipment.The herringbone groove thrust bearings(HGTBs),with its advantages of high axial rigidity,long service life,and good stability,can be widely applied in this type of power equipment for beneficial effects.In recent years,researchers have conducted extensive studies to develop cost-effective and environmentally friendly lubricants for HGTBs,achieved by incorporating additives into water.This paper focuses on investigating water-lubricated herringbone groove dynamic pressure thrust bearings as the subject of the research.The dynamic characteristics of this bearing are investigated by establishing a bearing flow field analysis model and conducting theoretical analysis and experimental research.The following section presents the main research content and results:(1)The investigation focused on the lubrication mechanism of waterlubricated HGTBs and the impact of structural parameters on their dynamic performance.Initially,an analysis model for the flow field within the bearing was established,enabling the determination of pressure,velocity,and temperature distribution of the water film through numerical calculations.This facilitated an exploration of the lubrication mechanism of the water film and an examination of how structural parameters influenced the dynamic performance of the bearing.Notably,when the bearing clearance was set at 10 μm,the thrust bearing demonstrated favorable lubrication performance.Specifically,optimal results were achieved with a groove width ratio of 1,a helix angle ranging from 65° to70°,and a corner radius of 0.5 mm.(2)A skewed condition model was developed for water-lubricated HGTBs to address rotor deformation issues caused by excessive external loads during operation.The analysis focused on flow field distribution and mechanical characteristics of the HGTBs under varying skew angles.The results revealed an uneven circumferential pressure distribution of the clearance fluid film resulting from shaft inclination.Specifically,the side with a larger clearance exhibited lower fluid film pressure,while the side with a smaller clearance experienced higher pressure.(3)A multi-input multi-output prediction model was introduced to assess the dynamic performance of water-lubricated HGTBs.Simulation data was utilized as input parameters for predicting the dynamic performance of the bearings.By considering load capacity as an example,it was observed that the WOA-BP algorithm model demonstrated superior prediction accuracy,exhibiting a mean absolute error(MAE)that was 113%higher compared to the BP model.(4)Experimental tests were performed to evaluate the performance of water-lubricated HGTBs based on theoretical analysis.The results revealed a significant increase in axial vibration when the rotational speed exceeded5000 rpm,while temperature fluctuations remained minimal.Moreover,the experimental results aligned with the predicted data.