OKÁL, M. Chování plastického maziva v EHL kontaktech kuličkových ložisek [online]. Brno: Vysoké učení technické v Brně. Fakulta strojního inženýrství. 2025.
The dissertation explores the crucial role of grease components in the elastohydrodynamic contact of ball bearings, particularly focusing on their ability to form an effective lubricating film. Ball bearings are integral to numerous engineering applications, yet significant gaps remain in our understanding of how greases perform in these critical systems. While commonly used methods, such as tribometers in ball-on-disc configurations and testing on actual ball bearings, offer insights, they fall short in providing comprehensive data. The ball-on-disc configuration oversimplifies bearing geometry, while real bearing tests lack direct analysis of the contact area. The student successfully identified key problems that needed to be addressed. Throughout his studies, he acquired proficiency in the experimental methods necessary to tackle the challenges at hand. He effectively carried out the required experiments and published the results in journals with an impact factor. In addition, he collaborated with other researchers worldwide to conduct essential experiments for validating the findings. The student demonstrated the ability to work independently on the assigned topic. He analyzed the issue based on a critical review of available publications and prepared an overview of the current state of knowledge, from which he identified key problems to address. He proposed a solution approach, conducted the experiment, and drew conclusions from the analysis of obtained results, which contributed to advancing the understanding of the topic. He completed all required exams and met the other criteria for the PhD program. His performance clearly reflects the skills needed to successfully complete a PhD. A novel approach is introduced, combining existing methods with experiments using a ball-on-ring configuration device that accurately simulates the realistic contact conditions of a ball bearing. The results offer valuable insights that will directly impact the development of more precise lubrication solutions and improved bearing performance, making this research essential for advancing both industrial applications and theoretical models in lubrication science.
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eVSKP id 163123