Friction and Temperature Reduction in a Mechanical Face Seal by a Surface Texturing: Comparison between TEHD Simulations and Experiments

International audienceMechanical face seals are used to avoid fluid leakage from pressurized zones to the environment in many rotating machineries. The initial research into the lubrication mechanism of these components was initiated several decades ago and numerous studies, both theoretical and experimental, have been carried out on the subject. Surface texturing has been of growing interest in recent years, but only a few studies have been devoted to textured mechanical face seals. Thus, the aim of the present work is to provide experimental, as well as theoretical, results with a comparison of smooth and textured seals. The temperatures of the seals are measured by means of infrared thermography. A 50% reduction in friction for the whole speed range and a reduction in the temperature rise of the sealing interface, attaining 40% at the highest speed values, are reported. Because it is not possible to measure the film thickness experimentally, a numerical thermoelastohydrodynamic model is used, taking into account the seal face deformations. A comparison between the experimental and theoretical temperatures allows the model to be validated. It is shown that, as expected, the film thickness increases with speed as a result of the pressure generated in the dimples. However, after a threshold, it starts to decrease because of the detrimental effect of thermal deformation. These results show that fluid solid coupling must be considered when designing the surface texture for a mechanical seal