Influence of Crack on Structure Vibration of Gear Tooth
This paper presents a theoretical model for analyzing the dynamic characteristic such as natural frequencies and vibration mode shapes of cracked gears. The influence of crack position and crack size on the dynamic characteristic of gears is thoroughly investigated using the proposed theoretical model as well as the finite element method (FEM) for the sake of model validation. The theoretical analysis and numerical simulation show that the influence of crack size and crack position on the dynamic responses of cracked gears is significant and that the influence of crack position is larger than that of crack size. The natural frequencies drop with the increase of crack size and the low order natural frequencies drop more notably. The natural frequencies drop more significantly when crack is located at tooth root than at tooth tip. The vibration mode shapes of cracked gear tooth are very different from those of gear tooth without crack, and the vibration amplitude increases significantly in crack neighborhood. These observations are very valuable for damage detection and fault diagnosis of gear system.
KeywordsGear Crack Structure vibration Dynamic characteristic Finite element method Simulation
This work is supported by the Chinese Natural Science Fund (50575187), the Chinese Aviation Science Fund (01I53073), and the Natural Science Fund of Shaanxi Province in China (2004E219). Grateful acknowledgments are also given to the China Scholarship Council for sponsoring this work.
- 3.Yao, H.L., Sun, W., Wen, B.C.: Model based online diagnosis of rotating machinery structural damage. In: Proceedings of the Asian Pacific Conference for Fracture and Strength (APCFS’06), Sanya, Hainan Island, China, 22–25 Nov 2006, pp. 327–331Google Scholar
- 4.Shen, Y.J., Yang, S.P., Xing, H.J.: Nonlinear dynamics of a spur gear pair with fault. In: Proceedings of the Asian Pacific Conference for Fracture and Strength (APCFS’06), Sanya, Hainan Island, China, 22–25 Nov 2006, pp. 170–174Google Scholar
- 6.Lin, J., Qu, L.S.: Signal time-frequency-entropy and its application in crack identifying of gear. Mech. Transmission 22(2), 37–39 (1998)Google Scholar
- 7.Berri, S., Klosner, J.: Dynamic of a transmission system having a cracked gear tooth. In: Proceedings of the 2000 ASME Design Engineering Technical Conference, Baltimore, MD, 10–13 Sept, 2000, pp. 82–88Google Scholar
- 8.Liu, L., Pines, D.J.: Static effects of tooth crack on a spur gear pair. In: Proceedings of the International Conference on Mechanical Transmission (ICMT’2001), Chongqing, China, 5–9 April 2001, China Machine Press, pp. 683–686Google Scholar
- 9.Lewicki, D.G.: Gear crack propagation path studies—guidelines for ultra-safe design, J. Am. Helicopter Soc. Jan, 64–72 (2002)Google Scholar
- 10.Lewicki, D.G., Spievak, L.E.: Consideration of moving tooth load in gear crack propagation predictions. Gear Technol. 19(1), 14–21 (2002)Google Scholar
- 11.Tang, L.W., Yang, T.Q: A research for identification root crack of tooth using acoustics signal. Vibrat. Measure. Diagn. 20(Supplement), 38–43 (2000)Google Scholar
- 12.Yang, C., He, Y.S.: Identification of gear tooth-root crack failure through solid sound wave signals. In: Proceedings of the ICMT’2001, Chongqing, China, 5–9 April, 2001, China Machine Press, pp. 386–388Google Scholar
- 14.Shao, R.P., Jia, P.R., Guo, W.L.: Dynamic analysis and three-dimensional finite element simulation of cracked gear. In: Proceedings of the APCFS’06, Sanya, Hainan Island, China, 22–25 2006, pp. 153–157Google Scholar