Tese

Aplicação da transformada integral generalizada em mancais radiais operando com fluidos não-newtonianos tipo lei da potência

This work present a study of the hydrodynamic lubrication of full journal bearings with non-Newtonian lubricants, obeying the power-law model. The formulation of the problem is obtained from the general equations of motion, after being taken over some simplifying assumptions inherent of the problem...

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Autor principal: MAGNO, Rui Nelson Otoni
Grau: Tese
Idioma: por
Publicado em: Universidade Federal do Pará 2017
Assuntos:
Acesso em linha: http://repositorio.ufpa.br/jspui/handle/2011/7598
Resumo:
This work present a study of the hydrodynamic lubrication of full journal bearings with non-Newtonian lubricants, obeying the power-law model. The formulation of the problem is obtained from the general equations of motion, after being taken over some simplifying assumptions inherent of the problem were taken. The regular perturbation method is applied on the governing equations for determining velocity profiles, and on generalized Reynolds Equation for Non-Newtonian lubricant. Solutions for borderline cases were obtained analytically. Then the generalized Reynolds equation is resolved through the Generalized Integral Transform Technique (GITT). For the calculation a computer code was developed in FORTRAN 90/95 which used the BVPFD subroutine from IMSL Library (2014). Numerical results for operational performance parameters such as pressure field, load capacity, Sommerfeld number, attitude angle, friction coefficient and axial flow rate were established and showed excellent agreement when compared with results available in the literature, for different eccentricities, aspect ratios "" and power-law index "n". Also it was studied the influence of surface texture, using sinusoidal, positive full and half wave roughness (transversal roughness). The transversal positive full wave is best for increasing the pressure, load carrying capacity and axial flow, again the results are excelente agreement with data available in the literature.