A heat transfer model for thermal distortions in high speed spiral groove gas lubricated face seals

Abstract

The thermal distortions of seal face caused by heat transfer directly affect the stability of seal operation. Here, a heat transfer analysis model of spiral groove gas face seal is established taking account of gas compressibility and choked flow effect. Then, a thermoelastohydrodynamic lubrication (TEHL) analysis is carried out based on the proposed heat transfer model, frictional heat flux, surface conduction heat flux, and film adsorption heat flux are calculated, and face distortions are also analyzed under different operating parameters including rotational speed, seal temperature and seal pressure. It is shown that, the adsorption heat induced by gas expansion makes the film cooling, which often leads complex temperature distributions and plays an important and non-ignored role in thermal distortions. For the spiral groove face seal, the increase of seal pressure and rotational speed makes the adsorption heat increase significantly due to pumping effect of grooves. The more important is that the thermal distortions may be controlled by changing seal width. Here, for the spiral groove face seal, the clearance can transfer divergent to convergent with increasing seal width from 5 mm to 13.1 mm. This provides a potential way for distortion control in gas face seal design.