Dynamics of Two-Phase Face Seals

Abstract

The effecb of phase change on load support is studied analytically for parallel and tapered face seals. A n adiabatic model for low Reynolds numberPo~u is considered. The descriptive fluid equations are integrated numerically to give opening force due t o j u i d film pressure. Loci of steady-state solutions are plotted for water to gzve cu.rves of load support as a function of film thickness. A quasisteady transient analysis is made for axial excursions of the seal rings. The general conclusions 'are:1. The 'load support generated by fluid pressure can be multivalued for a given film thickness. Axial disturbances,of the seal rings may lead to sudden dropsi n load support with three possible results. a) Sufficient damping may allow the seal to return to the previous equilibrium operating position. 6) The seal may collapse to a n equilibrium position of smaller film thickness where face contact is more likely and a sipzificantly higher operating temperature is assured. c) A limit cycle of self sustained oscillations i n the uxial direction mc~y occur damping is suficiently low.

Study of the fluid film vaporization in the interface of a mechanical face seal

“…According to Lebeck and Chiou [13], the seal faces profile also controls the appearance of puffing. In dynamic approaches, the authors considered the mass of the floating ring [14,15] and the squeeze of the film in more advanced simulations [11,16]. This type of model allows the simulation of puffing (oscillation of the film thickness) as well as the opening of the seal.…”

Effect of two-phase flow lubrication on sealing performance of spiral groove mechanical seal under high speed and low temperature conditions

“…Lau et al 7 and Yasuna and Hughes 8 independently proposed simplified models for designing two-phase film seals and a continuous boiling model for film seals, respectively. Beeler and Hughes 9 embarked on the exploration of the flow behavior of liquid and gas in two-phase flow at the sealing interface and its impact on sealing performance. Complementarily, Salant and Blasbalg 10 undertook a study on the motion and interaction of two-phase fluids in mechanical seals.…”