Effect of surface roughness on magnetohydrodynamic squeeze film characteristics between finite rectangular plates

The effect of surface roughness on the magnetohydrodynamic squeeze film behavior between two rectangular plates is analyzed. A generalized form of surface roughness pattern is considered. A stochastic random variable with non-zero mean, variance and skewness is used to model mathematically the surface roughness of the squeeze film bearings. The modified averaged stochastic Reynolds equation governing the squeeze film pressure is derived. The expressions for the squeeze film pressure, load carrying capacity and squeeze film time are obtained. Numerical computations of the results show that the negatively skewed surface roughness pattern increases the load carrying capacity and squeeze film time. On the contrary the performance of squeeze film suffers due to positively skewed surface roughness pattern. Further the magnetic effect characterized by the Hartmann number improves the performance of the squeeze film lubrication as compared to the classical non-conducting lubricant case.

► Surface roughness effect on MHD squeeze film.
► Modified averaged Stochastic Reynolds equation describes the model.
► Negatively skewed surface roughness pattern increases load capacity.
► Whereas positively skewed surface rough pattern has the opposite effect.
► The magnetic effect (conducting fluids) has improved effect compared with that of non-conducting ones.