Abstract: The improved two-control-volume model is used to compute the dynamic coefficients of see-through labyrinth seal, and the one-control-volume model is also introduced briefly. The theoretical results from the improved two-control-volume model are in well agreement with the experimental data, so the improved method is feasible. The influences of seal clearance and running speeds on dynamic coefficients for both the teeth-on-rotor and the teeth-on-stator seals are presented. Dynamic coefficients for a certain see-through labyrinth seal are calculated respectively using both one-control-volume and two-control-volume models, and the two kinds of results are compared. Some interesting conclusions are drawn.

Key words: Dynamic coefficients, See-through labyrinth seal, Steam turbine