رسالة جامعية
Resonance phenomena of polymer-covered cylinders under rolling contact ; Polymeeripinnoitettujen pyörivien kontaktitelojen resonanssi-ilmiöt
| العنوان: | Resonance phenomena of polymer-covered cylinders under rolling contact ; Polymeeripinnoitettujen pyörivien kontaktitelojen resonanssi-ilmiöt |
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| المؤلفون: | Karttunen, Anssi |
| المساهمون: | von Hertzen, Raimo, Prof., Aalto University, Department of Applied Mechanics, Finland, Insinööritieteiden korkeakoulu, School of Engineering, Sovelletun mekaniikan laitos, Department of Applied Mechanics, Tuhkuri, Jukka, Prof., Aalto University, Department of Applied Mechanics, Finland, Mechanics of Materials, Aalto-yliopisto, Aalto University |
| بيانات النشر: | Aalto University Aalto-yliopisto |
| سنة النشر: | 2015 |
| المجموعة: | Aalto University Publication Archive (Aaltodoc) / Aalto-yliopiston julkaisuarkistoa |
| مصطلحات موضوعية: | Mechanical engineering, vibration, wave propagation, resonance, polymer, viscoelasticity, contact, värähtely, etenevä aalto, resonanssi, polymeeri, viskoelastisuus, kontakti |
| الوصف: | In paper machines the paper is fed through the contact areas, the nips, between rolling cylinders which are often covered with polymers. A soft polymer nip gives the paper a glossy surface and a smooth thickness profile with uniform density. Although the use polymer covers is beneficial in terms of end-product quality, the covers also induce and suffer from harmful dynamic phenomena. In this dissertation two such phenomena, a self-excited vibration mechanism and a traveling wave phenomenon, were studied in detail to understand their essential features. At all instances, the studied system consisted of two steel-core cylinders with a polymeric cover on the other cylinder. The self-excited vibration mechanism was first investigated using a one-dimensional (1D) analytical model. It was found that the mechanism is active when the frequency of the cover deformation induced excitation is close to that eigenfrequency of the system, which corresponds to the eigenmode in which the cylinders are vibrating in opposite phases. The vibrations are strongest when the phase of the residual deformation of the cover leads the phase of the nip gap between the cylinders by 90 degrees. Next, simulations were performed using a two-dimensional (2D) plane strain finite element (FE) model and cover deformation patterns were obtained. The results from the 1D and 2D models were found to be in good agreement. Finally, the computational and obtained experimental results were compared to validate the model-based physical interpretations. The physical explanation given by the 1D analytical model for the self-excited vibration mechanism was found to be valid. The traveling wave phenomenon was first studied using a 2D plane strain FE model. A critical speed below which the traveling waves did not appear was calculated on the basis of a resonance condition using modal information from eigenmode analysis. After dynamic rolling contact simulations it was found that the traveling wave phenomenon is best described as a Rayleigh wave resonance in ... |
| نوع الوثيقة: | doctoral or postdoctoral thesis |
| وصف الملف: | application/pdf |
| اللغة: | English |
| ردمك: | 978-952-60-6502-1 978-952-60-6501-4 952-60-6502-6 952-60-6501-8 |
| العلاقة: | Aalto University publication series DOCTORAL DISSERTATIONS; 179/2015; [Publication 1]: Anssi T. Karttunen and Raimo von Hertzen. Polymer cover induced self-excited vibrations of nipped rolls. Journal of Sound and Vibration, 330, 3959–3972, 2011. DOI:10.1016/j.jsv.2011.03.016; [Publication 2]: Anssi T. Karttunen and Raimo von Hertzen. On the self-excited vibrations of a viscoelastically covered cylinder in rolling contact using FE method. Journal of Structural Mechanics – Special issue for NSCM-24, 44, 231–242, 2011.; [Publication 3]: Anssi T. Karttunen and Raimo von Hertzen. A numerical study of traveling waves in a viscoelastic cylinder cover under rolling contact. International Journal of Mechanical Sciences, 66, 180–191, 2013. DOI:10.1016/j.ijmecsci.2012.11.006; [Publication 4]: Anssi T. Karttunen and Raimo von Hertzen. Dynamic response of a cylinder cover under a moving load. International Journal of Mechanical Sciences, 82, 170–178, 2014. DOI:10.1016/j.ijmecsci.2014.03.026; 1799-4942 (electronic); 1799-4934 (printed); 1799-4934 (ISSN-L); https://aaltodoc.aalto.fi/handle/123456789/18507Test; URN:ISBN:978-952-60-6502-1 |
| الإتاحة: | https://doi.org/10.1016/j.jsv.2011.03.016Test https://doi.org/10.1016/j.ijmecsci.2012.11.006Test https://doi.org/10.1016/j.ijmecsci.2014.03.026Test https://aaltodoc.aalto.fi/handle/123456789/18507Test |
| رقم الانضمام: | edsbas.977B293A |
| قاعدة البيانات: | BASE |
| ردمك: | 9789526065021 9789526065014 9526065026 9526065018 |
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