A primary technology barrier preventing the operation of gas turbine engines and aircraft gearboxes at higher temperatures is the inability of currently used liquid lubricants to survive at the desired operating conditions over an extended time period. Current state-of-the-art organic liquid lubricants rapidly degrade at temperatures above 300 °C; hence, another form of lubrication is necessary...

Hydrodynamic performance of gas microbearings, fabricated with deep X-ray lithography and electroplating, will be presented in this article. Static performance in terms of load parameters and attitude angles was calculated using Molecular Gas Lubrication (MGL) theory. Threshold speed and allowable rotor mass were calculated to investigate safe operating conditions of the fabricated gas microbea...

In this study we present a numerical simulation for droplet spreading and evaporation on flat surfaces and in a semi-confined geometry. The model takes into account some of the coupled dynamics between the liquid and gas phases in an attempt to develop a coupled model for mass, energy and momentum transport. The dynamics of the liquid droplet are modelled using the lubrication framework and inc...

In high speed rotating machines such as turbines and generators, vibrations of a rotating shaft often hinder the smooth operation of the machine or even cause failure. Oil whip is one of such vibrations due to oil film action of journal bearing. Its mechanism and preventive method is explained and proposed in this paper. Further theoretical and experimental analyses are made for considering hea...

A typical reciprocating co~pressor consists of a motor, a pump, suction discharge system and a lubrication system. An integrated computer simulation model incorporating all these components simultaneously was developed to predict, evaluate and optimize the overall performance and reliability. For the given design variants of a compressor, the computer program first calculates the mass flow rate...