摘要采用旋转流变仪研究了 NLGI 3 锂基润滑脂在不同温度、不同长度下的直管和 不同曲率半径下的弯管流变特性的变化规律。基于润滑脂的流变结果和数据，得出 了不同温度下的润滑脂流变特性的变化规律，建立了润滑脂的直管流动的计算模型， 分析出了压力损失较小时的合适的曲率半径，并采用 Fluent 软件对润滑脂的直管和 弯管流动进行了数值模拟分析，得出了各温度、长度下的润滑脂直管和不同曲率半 径下的弯管流动过程中压力、速度和表观粘度分布情况。通过这些研究，揭示了不 同温度、长度和曲率半径对油脂输送压力的影响规律，为进一步提高润滑泵的润滑 效率和润滑质量，为润滑设备的设计和选择提供参考依据。结果表明：润滑脂具有 较高的屈服剪应力，表现出良好的黏温特性和剪切稀化特性，温度升高润滑脂的屈 服应力和表观黏度均下降，表现为更好的流动性；H-B 模型用于 NLGI 3 锂基润滑脂 的流动模拟是可行的，比使用宾汉模型模拟结果更为可靠；在一定范围内，弯管输 送损失压力随曲率半径的减小而减小，但超过一定值时不再具有实际研究效用。83318

毕业论文关键词：锂基润滑脂、赫谢尔—巴尔克利、计算流体动力学、压力损失、数值模拟分析

Abstract Using a rotary rheometer of NLGI 3 lithium grease at different temperatures。 The variation of rheological properties of straight pipe elbow under different lengths and different curvature radius。 The rheological results of grease and data based on the variation of rheological property of grease at different temperatures were obtained, established the calculation model of the straight tube flow of grease the analysis of the pressure loss is small, the appropriate radius of curvature, and the flow of software of Fluent grease straight pipes and pipe was simulated and analyzed, the conclusion that the temperature and pressure of flow process under the length of straight pipe and grease under the different radius of curvature of the apparent viscosity and velocity distribution through these studies, reveals the influence of different temperature, length and radius of curvature on the transporting pressure of oil, in order to further improve the efficiency of lubrication and lubrication oil pump to run quality Sliding device design and provide a reference, so it has significant。 Results show that: grease with higher yield shear stress showed good viscosity temperature characteristics and shear thinning properties and elevated temperature grease yield force and the apparent viscosity decreased, for better liquidity。

H-Bmodel for nlgi 3 lithium base grease flow simulation is feasible, than using Bingham model simulation results more reliable; within a certain range, pipe conveying pressure loss and decreases with the decrease of the radius of curvature, but beyond a certain value no longer has actual effectiveness studies。

Keywords:Radius of curvature、Herschel-Bulkley、CFD、pressure loss、 Numerical simulation analysis

目录

第一章 绪论 1

1。1 课题研究的背景和意义 1

1。2 国内外润滑技术现状及发展趋势 2

1。2。1 研究现状 2

1。2。2 发展趋势 2

1。3 非牛顿流体力学的研究内容和研究方法 3

1。31 非牛顿流体力学的研究内容 3

1。3。2 非牛顿流体力学的研究方法 4

1。4 课题研究的主要内容 5

第二章 润滑泵介绍