Thermal analysis of bearing used in disc type centrifugal separator

Disc type centrifuges are machines that use high G force to separate heterogeneous mixtures of different densities. The aim of this study is to increase the heat transfer rate in order to reduce the temperature of the lubricant used in disc type centrifugal separators. This provides the correct formation of the oil film between the balls and cages of the bearings that absorb the vertical and horizontal forces used in the machine. In this way the life of the bearing can be extended. To maintain a constant temperature of the lubricant, a fin was added to the oil chamber to enhance heat transfer. The oil chambers were tested under the same operating conditions for 2 cases with and without the fin. The results showed that the case without fin oil chamber reached a temperature of 61.5°C. While for the case of with fins, the temperature was measured 53.2°C. The total test duration was 7 hours. Thermal analysis was conducted, and the results were found to be similar to those obtained from the experimental test. Besides, the experimental study results were used as input parameters for the analysis which are carried out in COMSOL Multiphysics program. It has been concluded that the with fin oil chamber design is successful in maintaining the lubricant temperature at a constant value and can be further improved. Key Words: Bearing, Centrifugal separator, Extended surfaces, Lubricant oil, Thermal analysis