Numerical Visualization of Grease Flow in a Gearbox

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Numerical Visualization of Grease Flow in a Gearbox

Gearbox lubrication plays a decisive role in both load capacity and efficiency. It is necessary for the formation of a lubricant film in tribological contacts, and for heat dissipation. Grease lubrication is often applied to gearboxes at a low operating speed and means that, for example, less effort is required in sealing design compared to oil lubrication. Over the years, the computational fluid dynamics (CFD) method has frequently been applied to support the lubrication-related design of gearboxes. However, very few studies have focused on grease lubrication. Whereas oil can generally be considered as Newtonian fluid, grease displays complex non-Newtonian flow behavior. In this study, the grease lubrication of a single-stage test gearbox is investigated by means of a finite-volume based CFD model. The numerical results on the grease flow show good accordance with high-speed camera recordings, and clearly display the lubrication mechanisms of “channeling” and “circulating”. These first results on grease flow simulation in gearboxes offer a starting point for further numerical studies.

Dynamics of Treatment Device for Die Casting of Metals

The aforementioned proves that the grease flow in mould treatment equipment can be regarded as a regulation system with the input quantity by medium pressure p1 above the grease level and with the output quantity by the grease flow speed.The utilization of treatment equipment for die casting of metal enhances both the working environment and work culture during die casting of metals. Application of grease flow regulation results in better repeatability of die casting cycle which positively influences the quality of castings.