An attempt has been made to analyze the performance of a magnetic fluid-based-squeeze film between longitudinally rough elliptical plates. A magnetic fluid is used as a lubricant while axially symmetric flow of the magnetic fluid between the elliptical plates is taken into consideration under an oblique magnetic field. Bearing surfaces are assumed to be longitudinally rough. The roughness of the bearing surface is characterized by stochastic random variable with nonzero mean, variance, and skewness. The associated averaged Reynolds’ equation is solved with appropriate boundary conditions in dimensionless form to obtain the pressure distribution leading to the calculation of the load-carrying capacity. The results are presented graphically. It is clearly seen that the magnetic fluid lubricant improves the performance of the bearing system. It is interesting to note that the increased load carrying capacity due to magnetic fluid lubricant gets considerably increased due to the combined effect of standard deviation and negatively skewed roughness. This performance is further enhanced especially when negative variance is involved. This paper makes it clear that the aspect ratio plays a prominent role in improving the performance of the bearing system. Besides, the bearing can support a load even when there is no flow. 1. Introduction The transient load carrying capacity of a fluid film between two surfaces having a relative normal velocity plays a crucial role in frictional devices such as clutch plates in automatic transmissions. Archibald [1] studied the behaviour of squeeze film between various geometrical configurations. Subsequently, Wu [2, 3] investigated the squeeze film performance mainly for two types of geometries, namely, annular and rectangular when one of the surfaces was porous faced. Prakash and Vij [4] discussed the load carrying capacity and time height relations for squeeze film performance between porous plates. In that study various geometries such as circular, annular, elliptical, rectangular, conical, and truncated conical were considered. Besides, a comparison was made between the squeeze film performance of various geometries of equivalent surface area and it was established that the circular geometry registered the highest transient load carrying capacity, other parameters remaining same. The above studies dealt with conventional lubricant. Verma [5] considered the application of magnetic fluid as a lubricant. The magnetic fluid consisted of fine magnetic grains coated with a surfactant and dispersed in a non-conducting magnetically
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