Cavitation model in journal bearing for application in rotating machinery

• Grant number: 17/07507-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2017
• End date: December 31, 2017
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Gregory Bregion Daniel
• Grantee: Rafael Sofner Domingues
• Host 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

Among the faults considered in rotary machines is the cavitation in hydrodynamic bearings, capable of causing serious problems to the rotor, such as increase of vibration, metal-to-metal contact and even bearing wear. For this reason, it becomes imperative to identify, as soon as possible, when a machine is operating in cavitation condition, in order to actuate quickly in the system and to mitigate critical problems. Thus, the development of robust and efficient models to describe the cavitation in hydrodynamic bearings is necessary to assist the identification of this phenomenon in the rotating system response. In this context, this study aims to evaluate different cavitation models applied to cylindrical hydrodynamic bearings. For this, a comparison should be performed between the cavitation models proposed by Elrod (1981) and Nowald et al. (2016), in order to verify the main differences in the lubrication conditions and hydrodynamic forces resulting in the bearing. This project falls within the scope of thematic project 2015/20363-6 "Fault Tolerant Identification and Control in Rotating Systems" with regard to the cavitation approach as an operational fault condition of the bearing, since such models must be applied in modeling of the rotor-bearing system. The models developed in this scientific initiation project should be used in the fault detection and identification models, in turn, in the dissertations and theses in progress within the scope of the thematic project 2015/20363-6. (AU)