Improving thermal performance of mechanical seals via surface texturing

Abstract

The effectiveness of using textured surfaces on the mechanical face seal mating ring to enhance thermal performance of seal rings was experimentally demonstrated in a recent paper. 1 Further experiments show that the dimples engraved on the primary ring outer surface can also reduce the rings’ contact face temperature. Interestingly, however, when both rings are treated, the seal sets just show slightly better temperature reduction than a single textured ring. An appropriate heat transfer augmentation coefficient is defined and used to estimate the surface heat transfer coefficient of textured mating ring. The surface heat transfer coefficient of textured primary ring is also estimated. To understand the nature of heat transfer of surface texture, a computational fluid dynamics (CFD) analysis was carried out using ANSYS Fluent. The turbulent Reynolds stress model was adopted in the analysis with liquid hydrocarbon as the working fluid. The flow structure within a dimple, which demonstrates the working mechanism of dimples’ heat transfer augmentation, is numerically displayed. The thermal performance of dimpled surfaces is evaluated based on the dimples depth-to-diameter ratio, size, arrangement, and shape of dimples. The comparison of Nusselt numbers distribution of dimpled surface and conventional surface is also presented.