| Although extensive research has been conducted in the area of thermohydrodynamic lubrication, there are many aspects of the field of hydrodynamics that need deeper understanding. One such issue involves the combination of various flow regimes and flow types, this includes the appearance of turbulence, temperature effects with roughness and the presence of cavitation with roughness. Although various forms of the Reynolds equation are well suited for handling these aspects as individual occurrences, there is further need for investigation in the mixed lubrication regime.; This study attempts to quantify the combined effects of turbulence, cavitation modeling, and surface roughness. An attempt is also made to understand the cause of disagreement between the various turbulent models, cavitation models, and surface models.; A Generalized form of the Reynolds equation was numerically solved allowing for constant and variable lubricant properties as a function of temperature. The Generalized Reynolds and the three dimensional thermal energy equations were solved using a finite volume method. The program is capable of operating under various conditions, i.e. Isothermal or full heat transfer, turbulence or laminar, and polished surface or in the presence of surface effects. The data is presented graphically by means of the pressure profile, load carrying capacity, friction force, side leakage, etc.; It was found that models do not lend themselves to mixed analysis, some aspects of various models contradict or magnify certain variables. This creates large errors or even catastrophic effects in the pressure field. One example is the combination of the turbulence models with surface roughness models, both these models successfully operate independently by altering the viscous effects in the Generalized Reynolds equation but when they are combined the viscous contribution becomes magnitudes different, thus poorly predicting the pressure. |
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