| Hydrodynamic mechanical seal is the most active fields in modern sealing technology, while there are few studies on hydrostatic mechanical seal relatively, the study on convergent gap mechanical seal is hardly paid more attention to. Convergent gap mechanical seal belongs to controlled leakage, hydrostatic balanced, non-contact and liquid-film type face seal. It is often applied in the lower primary sealing assembly of the reactor coolant pump of the nuclear power plant. Hydrostatic liquid film makes the best lubrication and cooling of the friction pairs, so that, the hydrostatic mechanical seal can be operated under high pressure and high speed. By setting up three-dimensional numerical model of the radically tapered mechanical seal, which is agreed with the actual physical model, this paper carries out the numerical simulation of the flow field for the liquid film of the seal gap and makes ready for the further research later.A theoretical analysis model was developed for the flow in convergent gap mechanical seal by the software GAMBIT. This paper is on the basis of computational fluid dynamics, founded on the finite volume method (FVM), used the software FLUENT, a three-dimensional numerical simulation of the pressure-velocity coupling was preformed for the liquid film of the seal gap. The pressure and the velocity distributions of the liquid film were carried out. The effect of sealing structure parameters (width of sealing surface and cone angle) and operation parameters on sealing performance was analyzed. The gap and leakage in steady station and under a special condition were calculated.In a word, through deeply studying the flow field performances of hydrostatic convergent gap mechanical seal, this dissertation offers theoretical support for the engineering design and application of the reactor coolant pump mechanical seal. And a theoretical basis is made for the further study such as dynamic stability, mechanical and thermal deformations.
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