﻿ 航空燃油柱塞泵滑靴副混合润滑特性数值仿真<sup>*</sup>
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Numerical simulation of hybrid lubrication characteristics of slipper pair of aviation fuel piston pump
FU Jiangfeng, LI Huacong, ZENG Xiaqing, LIU Xianwei
College of Power and Energy, Northwestern Polytechnical University, Xi'an 710072, China
Received: 2017-05-15; Accepted: 2017-08-11; Published online: 2017-09-27 18:21
Foundation item: Aeronautical Science Foundation of China (20150653006); the Fundamental Research Funds for the Central Universities (G2017KY0003)
Corresponding author. FU Jiangfeng, E-mail: fjf@nwpu.edu.cn
Abstract: The aim of this paper was to solve the slipper pair lubrication problem of the aero fuel piston pump under the mixed support of dynamic and static pressure. Based on the mathematical model of kinematics and dynamics of slipper pair, the mathematical model of the hybrid lubrication of the slipper pair was established based on the dynamic pressure effect caused by the static pressure support and the irregular spatial curve of sliding shoe movement. Then the lubrication characteristics of slipper pair were simulated based on the finite volume method, and the variation law of the oil film thickness, the influence factors of the oil film pressure distribution and the anti-sliding performance of the sliding shoe were analyzed. The simulation results show that the variation trend of the oil film thickness obtained by the hybrid lubrication is consistent with the actual lubrication state, the thickness of the oil film, the maximum inclination angle of the slipper and the rotor speed have an important influence on the dynamic pressure effect, and the inlet pressure of the slipper pair mainly affects the static pressure of the oil film. The anti-overturning ability of the sliding shoe can be enhanced by increasing the working radius of the bottom surface of the sliding shoe or reducing the radius of the oil pool of the sliding shoe center, so as to counteract the overturning moment of the sliding shoe.
Key words: fuel piston pump     slipper pair     dynamic pressure effect     lubrication characteristics     static pressure support

1 航空燃油柱塞泵滑靴副动力学与油膜动静压润滑模型 1.1 滑靴副运动学及动力学模型

 图 1 航空燃油柱塞泵滑靴副结构 Fig. 1 Slipper pair structure of aviation fuel piston pump

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 图 2 滑靴副受力仿真 Fig. 2 Force simulation of slipper pair

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1.2 油膜动静压润滑模型

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2 滑靴副动静压混合润滑特性计算 2.1 基本假设

1) 与黏性力相比，忽略油膜受到的体积力和惯性力，如重力和离心力。

2) 燃油为Newton流体，流动为层流，不考虑油膜中的湍流和涡流。

3) 油液在滑靴副壁面无滑移，即油膜在滑靴底面和斜盘表面的油层速度与壁面速度相同。

4) 在润滑油膜厚度方向上，流体黏性和压力保持不变。

5) 与油膜厚度相比，固体表面的曲率半径很大，因而忽略油膜曲率引起的速度方向的变化。

6) 滑靴副属于窄面密封，假设油膜温度场均匀分布。

2.2 边界条件

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3 数值仿真分析 3.1 中心油膜厚度和最大倾斜角

 图 3 滑靴副中心油膜厚度 Fig. 3 Central oil film thickness of slipper pair
 图 4 滑靴最大倾斜角 Fig. 4 Maximum inclination angle of slipper

 图 5 α=180°时的油膜厚度分布 Fig. 5 Distribution of oil film thickness with α=180°

3.2 影响油膜压力分布的因素

1) 动压效应的仿真验证

α=180°即吸排油区切换点进行数值模拟，由图 3图 4可知此时中心油膜厚度为10.6 μm，最大倾斜角为9.5×10-4 rad。按此条件数值模拟得到的结果如图 6所示。

 图 6 实际情况下的油膜压力分布 Fig. 6 Distribution of oil film pressure in actual situation

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2) 中心油膜厚度

 图 7 不同中心油膜厚度下的油膜压力分布 Fig. 7 Oil film pressure distribution under different central oil film thickness

3) 滑靴最大倾斜角

 图 8 不同最大倾斜角下的油膜厚度及压力分布 Fig. 8 Oil film thickness and pressure distribution under different maximum inclination angles

4) 转子转速

 图 9 不同转子转速下的油膜压力分布 Fig. 9 Distribution of oil film pressure under different rotor speeds

5) 供油压力

 图 10 不同供油压力下的油膜压力分布 Fig. 10 Distribution of oil film pressure under different oil supply pressure

 图 11 不同供油压力下的油膜动静压支承力 Fig. 11 Dynamic and static bearing force of oil film under different oil supply pressure

3.3 结构参数对抗倾覆能力的影响

 图 12 不同滑靴底面工作半径下的油膜压力分布 Fig. 12 Distribution of oil film pressure underdifferent working radius of slipper bottom

 图 13 不同滑靴底面工作半径下的油膜动静压支承力 Fig. 13 Dynamic and static bearing force of oil film under different working radiuses of slipper bottom

 图 14 不同中心油池半径下的油膜压力分布 Fig. 14 Distribution of oil film pressure under different central oil pool radius

 图 15 不同中心油池半径下的油膜动静压支承力 Fig. 15 Dynamic and static bearing forces of oil film under different central oil pool radiuses

4 结论

1) 滑靴合力的变化对于滑靴副油膜的润滑至关重要，建立滑靴副混合润滑模型时必须考虑滑靴在旋转运动过程中所受到的离心力和摩擦力；对比分析静压润滑和混合润滑机理下的油膜厚度仿真结果可知，动压效应在整个支承力中占28%，因此不可忽略，因动压效应的产生使得动静压混合支承所得到的油膜厚度整体偏小。对比滑靴在α=180°时所受合压紧力与动静压混合支承力计算结果，动静压混合支承力较滑靴合压紧力的计算误差仅为0.9%，表明动静压混合润滑现象应更符合滑靴副实际的润滑状态，且所建立的动静压混合润滑数学模型是可信的。

2) 中心油膜厚度、滑靴最大倾斜角和转子转速是动压效应的主要影响因素，其产生的动压的主要作用在于保障滑靴抗倾覆能力；而滑靴副进口压力即柱塞泵供油压力是油膜的静压作用的主要影响因素，对油膜的静压作用影响占比为62%~85%，但进口压力对动压效应的变化影响甚微。滑靴底面工作半径和中心油池半径对油膜的动压效应影响非常大，其中滑靴底面工作半径增加2 mm，动压效应可增加5.59倍，中心油池半径减小2 mm，动压效应可增加2.67倍。若要提升滑靴的抗倾覆能力，可通过优化以上参数保障滑靴的抗倾覆能力。

 [1] 陈永琴. 航空燃油柱塞泵运动学与动力学特性分析研究[D]. 西安: 西安电子科技大学, 2012. CHEN Y Q. Analysis of kinematics and dynamics characteristics of aviation fuel piston pump[D]. Xi'an: Xi'an Electronic and Science University, 2012(in Chinese). http://cdmd.cnki.com.cn/Article/CDMD-10701-1013114445.htm [2] IVANTYSYNOVA M. A new approach to the design of sealing and bearing gaps of displacement machines[C]//Proceedings of the 4th JFPS International Symposium on Fluid Power. Tokyo: JFPS, 1999: 45-50. [3] WIECZOREK U, IVANTYSYNOVA M. Computer aided optimization of bearing and sealing gaps in hydrostatic machine-The simulation tool CASPAR[J]. International Journal of Fluid Power, 2002, 3 (1): 7–20. DOI:10.1080/14399776.2002.10781124 [4] PELOSI M, IVANTYSYNOVA M. Heat transfer and thermal elastic deformation analysis on the piston/cylinder interface of axial piston machines[J]. Journal of Tribology, 2012, 134 (4): 119–128. [5] SCHENK A, IVANTYSYNOVA M. A transient thermoelastohydrodynamic lubrication model for the slipper/swashplate in axial piston machines[J]. Journal of Tribology, 2015, 137 (3): 031701. DOI:10.1115/1.4029674 [6] DEEKEN M. Simulation of the tribological contacts in an axial piston machine[C]//ASME 2004 International Mechanical Engineering Congress and Exposition. New York: ASME, 2004: 71-75. [7] WOHLERS A, MURRENHOFF H. Tribological simulation of hydrostatic swash plate bearing in an axial piston pump[C]//Power Transmission and Motion Control Symposium, 2007: 129-144. [8] SCHLEIHS C, VIENNET E, DEEKEN M. 3D-CFD simulation of an axial piston displacement unit[C]//9th International Fluid Power Conference, 2014: 332-343. [9] 徐兵, 李迎兵, 张斌, 等. 轴向柱塞泵滑靴副倾覆现象数值分析[J]. 机械工程学报, 2010, 46 (20): 161–168. XU B, LI Y B, ZHANG B, et al. Numerical analysis of the phenomenon of sliding pair of axial piston pump[J]. Journal of Mechanical Engineering, 2010, 46 (20): 161–168. (in Chinese) [10] 李迎兵. 轴向柱塞泵滑靴副油膜特性研究[D]. 杭州: 浙江大学, 2011. LI Y B. Axial piston pump slipper oil film characteristics of slide[D]. Hangzhou: Zhejiang University, 2011(in Chinese). http://cdmd.cnki.com.cn/article/cdmd-10335-1011068894.htm [11] 刘洪, 苑士华, 彭增雄. 轴向柱塞泵滑靴油膜动态仿真[J]. 北京理工大学学报, 2011, 31 (11): 1282–1286. LIU H, YUAN S H, PENG Z X. Dynamic simulation of oil film in sliding piston pump[J]. Journal of Beijing Institute of Technology, 2011, 31 (11): 1282–1286. (in Chinese) [12] 于思淼. 轴向柱塞泵用滑靴流体静动压支撑的特性分析及结构优选[D]. 哈尔滨: 哈尔滨工业大学, 2013. YU S M. Characteristics analysis and structure optimization of Slipper with static and dynamic pressure support used in the axial piston pump[D]. Harbin: Harbin Institute of Technology, 2013(in Chinese). http://cdmd.cnki.com.cn/Article/CDMD-10213-1014001865.htm [13] 王亚军. 高压高速轴向柱塞泵滑靴性能研究[D]. 北京: 北京理工大学, 2014. WANG Y J. Research on the performance of high speed axial piston pump slipper[D]. Beijing: Beijing Institute of Technology, 2014(in Chinese). http://cdmd.cnki.com.cn/article/cdmd-10007-1014086752.htm [14] 魏超, 胡纪滨, 薛冰, 等. 表面微结构对轴向柱塞泵滑靴润滑特性的影响[C]//第十一届全国摩擦学大会, 2013: 1-7. WEI C, HU J B, XUE B, et al. Effect of surface microstructure on lubrication characteristics of sliding shoe of axial piston pump[C]//The 11th of Tribology Conference, 2013: 1-7(in Chinese). [15] 何必海, 孙健国, 叶志锋. 航空燃油柱塞泵滑靴静压润滑油膜计算分析[J]. 航空动力学报, 2009, 24 (12): 191–197. HE B H, SUN J G, YE Z F. Calculation and analysis of lubricating oil film of sliding piston for aviation fuel piston pump[J]. Journal of Aerospace Power, 2009, 24 (12): 191–197. (in Chinese) [16] 何必海, 孙健国, 叶志锋. 燃油柱塞泵滑靴副和配流副油膜计算研究[J]. 航空动力学报, 2010, 25 (6): 1437–1442. HE B H, SUN J G, YE Z F. Study on the oil film of the slipper pair and the oil distribution pair of fuel injection pump[J]. Journal of Aerospace Power, 2010, 25 (6): 1437–1442. (in Chinese) [17] 徐佩佩, 叶志锋, 王彬. 航空燃油柱塞泵滑靴油膜的多目标优化设计[J]. 航空动力学报, 2014, 29 (8): 1981–1986. XU P P, YE Z F, WANG B. Multi objective optimization design of oil film for sliding piston oil pump[J]. Journal of Aerospace Power, 2014, 29 (8): 1981–1986. (in Chinese) [18] 林硕, 苑士华, 刘洪. 考虑油膜非均匀性的滑靴润滑特性研究[J]. 北京理工大学学报, 2014, 34 (4): 358–362. LIN S, YUAN S H, LIU H. Study on the lubrication characteristics of sliding shoes considering the heterogeneity of oil film[J]. Journal of Beijing Institute of Technology, 2014, 34 (4): 358–362. (in Chinese)

#### 文章信息

FU Jiangfeng, LI Huacong, ZENG Xiaqing, LIU Xianwei

Numerical simulation of hybrid lubrication characteristics of slipper pair of aviation fuel piston pump

Journal of Beijing University of Aeronautics and Astronsutics, 2018, 44(5): 939-950
http://dx.doi.org/10.13700/j.bh.1001-5965.2017.0309