A bench-mounted, self-contained apparatus to demonstrate the pressure distribution across the fi lm of oil in a Michell tilting pad slider bearing. Helps to prove Reynold’s equation for pressure gradient in fl uid film.
Key Features
• Proven design, based on a machine created by the Department of Mechanical Engineering, Imperial College, London
• Accurately mimics a Michell tilting pad, fl uid-lubricated slider bearing
• Helps to prove Reynold’s equation for pressure gradient in a fl uid fi lm
• Includes a variable speed motor control
• Fully adjustable pad (tilt) angle
• Includes oil and a viscometer
Description
The Department of Mechanical Engineering (Imperial College, London), created the original design for this apparatus. It mimics a tilting pad fl uid-lubricated slider bearing, invented by A G M Michell.
The bench-mounting unit has an aluminium plate (pad) mounted above a continuous loop fl at belt. The belt runs in an oil reservoir to provide a continuous supply of oil under the pad. This creates a pressurised fi lm of oil between the pad and the belt.
A set of thirteen graduated tubes show the oil pressure across and along the fi lm under the pad.
Included is a variable speed control to control the speed of the motor that turns the belt. Students vary the belt speed to fi nd the relationship between sliding speed, oil viscosity and pressure distribution.
Two eccentric shafts hold the pad so students can adjust the angle of tilt of the pad. This helps students to fi nd the relationship between pressure distribution and fi lm thickness. Micrometers measure the leading and trailing edge positions of the pad.
Included with the apparatus is a container of oil and a viscometer to measure the viscosity of the oil.
Learning outcomes
Study of:
• Pressure distributions in a tilting pad bearing.
• Infl uence of sliding speed and viscosity on the pressure distribution in the bearing and comparison with calculations based on Reynold’s equation.
• The relationship between pressure and the fi lm thickness at the trailing edge of the pad.
