微小型涡喷发动机的离心叶轮轴向长度相比转轴长度不可忽略,可将其看作拉杆转子结构。为研究该拉杆转子结构的弯曲振动特性,建立了包含连接面的简支梁数学模型,应用结合面接触分形理论,推导了预紧力、粗糙度对拉杆弯曲振动特性的数学关系。通过算例研究,得出了预紧力、粗糙度对拉杆弯曲振动特性的影响趋势。结果表明:连接面所需的最小预紧力随着粗糙度的增加呈指数增长;仅考虑连接面刚度变化的情况下,拉杆固有频率与对数坐标下的预紧力之间呈S型曲线关系,粗糙度值越大,S曲线的潜伏期越长;同时考虑预紧力对连接面刚度和拉杆抗弯刚度的影响,当粗糙度较小时,拉杆固有频率随预紧力上升而上升;粗糙度较大或预紧力较大时,拉杆固有频率随预紧力上升而下降。
Abstract
A micro turbine engine rotor could be considered as a rod fastening rotor, since the disc thickness of its centrifugal impeller is not negligible compared with the rotor length.To gain an insight into the rotor lateral vibration characteristics, a simply supported Bernoulli-Euler beam including connecting surfaces was built.By means of the fractal contacting theory, the mathematical expression for describing the effects of the tightening force and surface roughness on the lateral vibration were derived, and the effect trends were clearly expounded by case studys.It shows that the needed minimal tightening force for connecting surfaces rises exponentially with roughness.Considering only the change of joint stiffness, the rotor natural frequencies vary along an S-shape curve with the increase of exponential tightening force.Furthermore, the more the roughness, the longer the incubation period of the S-shape curve.Considering both the changes of joint stiffness and rotor lateral stiffness, when the roughness and tightening force are small, the natural frequencies increase with the tightening force, on the contrary, the natural frequencies fall with the tightening force.
关键词
拉杆转子 /
预紧力 /
粗糙度 /
弯曲振动 /
微小型涡喷发动机
{{custom_keyword}} /
Key words
rod fastening rotor /
tighten force /
roughness /
lateral vibration /
micro turbine engine
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 钱征文,程礼,陈卫,等. 盘式拉杆转子双稳态振动特性[J]. 航空动力学报,2011, 40(8):1563-1568.
QIAN Zheng-wen, CHENG Li, CHEN Wei, et al. Analysis on bistable response of a disk-rod-fastening rotor [J]. Journal of Aerospace Power, 2011, 40(8):1563-1568.
[2] 李忠刚,陈照波,焦映厚,等. 分布式拉杆转子扭转振动系统[J]. 动力学与控制学报,2016, 14(2):143-146.
Li Zhonggang, CHEN zhaobo, JIAO Yinghou, et al. Analysis of characteristics of the torsional vibration of the distributed rod fastening rotor system[J]. Journal of Dynamics and control, 2016, 14(2):143-146.
[3] 边涛,谢寿生,任立通,等. 基于贝叶斯理论的拉杆转子模态特性确认[J]. 振动与冲击,2017,36(23):92-98.
BIAN Tao, XIE Shousheng, REN Litong, et al. Modal charactersitics confirmation of a rod-fastening rotor based on Bayesian theory. [J] Journal of vibration and shock. 2017, 36(23): 92-98.
[4] 饶柱石,夏松波,汪光明. 粗糙表面接触刚度的研究[J]. 机械强度,1994,16(2):71-75.
RAO Zhu-shi, XIA Song-bo, WANG Guang-ming. A study of contact stiffness of flat rough surfaces[J]. Journal of Mechanical Strength, 1994, 16(2):71-75.
[5] 何鹏,刘占生,张光辉 等. 分布拉杆转子动力学建模与分析[J]. 汽轮机技术,2010, 52(1):4-8.
HE Peng, LIU Zhansheng, ZHANG Guanghui et al. Dynamic modeling and analysis of distributed rod fastening rotor [J]. Turbine Technology,2010, 52(1):4-8.
[6] 温淑花. 结合面接触特性理论建模及仿真[M]. 北京:国防工业出版社,2012.
WEN Shu-hua. Theoretical modeling and simulation of contact surfaces characteristics[M]. Beijing:National Defense Industry Press,2012.
[7] 张锁怀,李俊南,吕超颖,等. 粗糙度和预紧力对周向拉杆转子轴承系统临界转速的影响[J]. 机械设计与研究,2018 34(2):65-70.
ZHANG Suo-huai, Li Jun-nan, Lv Chao-ying, et al. Influence of roughness and tighten force on critical speeds of the rod fastening composite special rotor-bearing system[J]. Machine Design and Research, 2018 34(2):65-70.
[8] 李辉光,刘恒,虞烈. 考虑接触刚度的燃气轮机拉杆转子动力特性研究[J]. 振动与冲击, 2012 31(7):4-8.
LI Hui-guang, LIU Heng, YU Lie. Dynamic characteristics of a rod fastening rotor for gas turbine considering contact stiffness[J].Journal of Vibration and Shock, 2012 31(7):4-8.
[9] 何谦,王艾伦,陈中祥,等. 考虑结合面法向刚度的拉杆转子轴向振动特性[J]. 中国机械工程, 2018 29(24): 2954-2958.
HE Qian, WANG Ailun, CHEN Zhongxiang, et al. The Axial Vibration Characteristics of Rod Fastening Rotor Considered Contact Normal Stiffness[J]. China Mechanical Engineering, 2018 29(24): 2954-2958.
[10] 卢明剑,孙岩桦,周健, 等. 拉杆组合转子的刚度修正及动力学建模[J]. 航空动力学报, 2016 31(9):2203-2209.
LU Ming-jian, SUN Yan-hua, ZHOU Jian, et al. Stiffness modification and dynamic modeling of a rod fastening rotor[J].Journal of Aerospace Power, 22016 31(9):2203-2209.
[11] 王艾伦,骆舟. 拉杆转子扭转振动研究[J]. 振动与冲击, 2009 28(5):165-168.
WANG Ai-lun, LUO Zhou. Study on rod fastening rotor’s torsional vibration[J]. Journal of Vibration and Shock, 2009 28(5):165-168.
[12] 卢明剑,耿海鹏,徐国徽,等. 预紧饱和下盘式周向拉杆转子-轴承系统动力学特性分析及实验研究[J]. 振动工程学报, 2014 27(1):111-117.
LU Mingjian, GENG Haipeng, XU Guohui, et al. Analytical and experimental study on dynamic characters of rod-fastening rotor-bearing system under saturated pretension[J]. Journal of Vibration Engineering, 2014 27(1):111-117.
[13] 胡海岩. 机械振动基础[M]. 北京:北京航空航天大学出版社, 2005.
HU Hai-yan. Basic Theory of Mechanical Vibration[M], Beijing: Beijing University of Aeronautics and Astronautics Press,2005.
[14] 方兵. 精密数控机床及典型结合面理论建模与实验研究[D]. 长春:吉林大学, 2012.
FANG Bing. Theoretical modeling and experimental study of precision CNC machine tools and its typical interface[D], Changchun: Jilin University,2012.
{{custom_fnGroup.title_cn}}
脚注
{{custom_fn.content}}