The effect of lubrication film thickness on thermoelastic instability under fluid lubricating condition

An idealized model consisting of a thermal conductor and a thermal insulator separated by a thin layer of lubricating fluid is developed to investigate thermoelastic instability with fluid lubrication. The governing equations are solved for the critical speed. A new dimensionless parameter H₀ is defined to predict the critical speed. Furthermore, the effects of various materials and the wavelength of perturbations on thermoelastic instability are discussed. It has been found that the migration speed of hot spots is nonzero, but typically very slow compared with the sliding speed and the relation between the critical speed and the fluid film thickness is non-linear. In addition, a material with low elastic modulus, low thermal expansion coefficient and high thermal conductivity will experience a high critical speed.