Effects of ovalization fault of hydrodynamic bearings on the dynamic response of rotating machinery

• Grant number: 19/11070-6
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): June 01, 2019
• Effective date (End): May 31, 2020
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal researcher: Katia Lucchesi Cavalca Dedini
• Grantee: Matheus Victor Inacio
• Home Institution: Faculdade de Engenharia Mecânica (FEM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 15/20363-6 - Fault tolerant identification and control of rotating systems, AP.TEM

Abstract

Hydrodynamic journal bearings are one of the most important components of rotating machinery due to their great influence on the dynamic behavior of the rotor. Despite their prominent role in these machines, they are susceptible to different types of faults, such as cavitation, wear, and ovalization. Ovalization faults occur due to plastic deformations in the bearing profile caused by non-symmetrical heating, manufacturing uncertainty, and assembly problems, which directly affects the rotor's response (Takabi and Khonsari, 2015). Thus, it is essential to evaluate the influence of the ovalization effects on the hydrodynamic forces of hydrodynamic bearings and, consequently, on the dynamic behavior of the rotating system, in order to characterize the responses of the system when operating in nominal and faulty conditions. In this context, this undergraduate scholarship proposal aims to expand the types of bearing faults considered initially in the thematic project, adding thus the fault condition by bearing ovalization. Therefore, the effects of ovalization fault of hydrodynamic bearings in rotating machinery will be investigated, in order to identify the main symptoms and characteristics on the dynamic response of the rotor in time and frequency domain. Understanding how the ovalization fault affects the dynamic behavior of the rotating system makes it possible to apply methodologies of diagnosis and identification of this type of fault, as well as differentiating it from other possible faults, such as bearing wear.