A quasi-transient approach for determining fluid film dynamic properties in dry gas seals

This paper proposes a novel technique for determining seal leakage rates, pressure distribution in the seal gap, equilibrium gap values, nonlinear fluid-film stiffness, and damping, based on a quasi-transient two-way fluid-rigid-body interaction (FRBI) simulation model. The model uses fluid-mesh deformation and rigid-body motion solvers during simulation. The developed model can be used to determine nonlinear fluid-film dynamic properties not only under equilibrium seal-gap conditions but also in cases of seal-ring separation caused by rotor vibration. The model can be used to simulate the operation of various seal types with different groove geometries. Additionally, the proposed model is not computationally intensive or time-consuming, making it a practical tool for designing new dry-gas-seal applications. Simulation results are compared with those obtained from classical analytical models, publicly available data, and experimental studies.