RHEOLOGICAL STUDY OF SAE 5W30 ENGINE OIL AND THEIR EMULSIONS
Bárbara Louise Lemos Drumond Silva1; Maryana Antonia Braga Batalha Souza1; Mabelle Biancardi Oliveira de Medeiros2; Edwin Elard Garcia Rojas1; José Adilson de Castro1
1 Universidade Federal Fluminense (UFF); 2 Centro Federal de Educação Tecnológica Celso Suckow da Fonseca (CEFET)
doi:10.20906/CPS/COB-2015-2363
Resumo
Bárbara Louise Lemos Drumond Silva*, barbara.drumond@gmail.com Maryana Antonia Braga Batalha Souza, mariana@metal.eeimvr.uff.br José Adilson de Castro, joseadilsoncastro@id.uff.br Pós-Graduação em Engenharia Metalúrgica (PPGEM), Universidade Federal Fluminense (UFF), Avenida dos Trabalhadores N° 420, CEP 27225-125, Volta Redonda, RJ, Brasil. Edwin Elard Garcia Rojas, edwin@vm.uff.br Pós-Graduação em Engenharia Mecânica (PGMEC), Universidade Federal Fluminense (UFF), Avenida dos Trabalhadores N° 420, CEP 27225-125, Volta Redonda, RJ, Brasil. Mabelle Biancardi Oliveira de Medeiros, mabelle@metal.eeimvr.uff.br Departamento de Engenharia de Alimentos, Centro Federal de Educação Tecnológica Celso Suckow da Fonseca (CEFET), Rua Voluntários da Pátria N° 30, CEP 27600-000, Valença, RJ, Brasil. * Corresponding author. Lubricating oils are used in surfaces subjected to contact forces playing important role on the friction characteristics and heat transfer during the relative motion. One of the most important single property of lubricating oil is its viscosity because it is directly related to the energy loss due to molecules friction and stress developed in the bulk liquid or emulsions. Another important factor which may cause changes in oil quality is the amount of water present in the emulsion. The water can be present in two forms, either as free water (related to corrosion) or suspended in tiny droplets. In case of suspended water, the dispersed water droplet size affects the stability of oil-in-water emulsion. This paper presents an analysis of viscosity and shear stress in the lubricating oils and their emulsions. The viscosity results for pure oil and their emulsions were discussed and compared with the viscosity results of these fluids obtained in a program based on the Unit Cell Model. The analysis of the rheological properties of emulsions showed that the viscosity versus shear rate curves exhibited a Newtonian behavior , which demonstrating that no changes occurs in relation to the emulsions pre
Palavras-chave: Lubricating oils; Rheological properties; Viscosity; Unit Cell Model