Hole-Pattern Damping Seals Simulation And Experiment Research

Hole-pattern annular seals can provide more damps to the rotor system, so they are widely accepted to improve rotor system’s stability. And friction factor is one of the significant parameters to measure their performance. We calculate seals’leakage and predict seals’rotordynamic coefficients by inputting friction factor. With friction factor we can provide seals which can decrease seals’leakage and make the rotor more stable.The article use plate test configuration to study hole-pattern annular seals’friction and its impact factors. The hole is12mm in diameter and0.9mm in depth. The working fluid is air. Meanwhile, the numerical simulation model of the clearance between the two plates is built to calculate the pressures field as well as the mass flow in the model. Then friction factor calculated by the two methods is compared to test the simulation’s accuracy.Further, the article build the numerical simulation model of the8mm diameter plate, exert the same loads to calculate. The research results show that the friction factors increase with the increase of the clearance and inlet pressure doesn’t impact friction factors significantly. Under the same conditions, small diameter hole-pattern seal has a better effect to prevent leakage.Then the article build the eccentric model of the hole-pattern seals, calculate the radial and axial forces in different clearances and different vortex ratios. Further, the article fit out the quadratic curves, calculate the stiffness and damping coefficients. When the diameter is8mm, clearance increases from0.3to0.5mm, direct stiffness drops from17.54to12.436, direct damping drops from-0.0466to-0.1181. Further, the article conjecture that stiffness decrease and direct damping increase as the friction factor increases.To test the stiffness and damping in the future, the article design a test rig. Measure the acceleration and displacement of the seal stator by exerting two vertical forces on the stator. The forces are supplied by two hydraulic shakers. Put the measured quantities into the stiffness and damping equation, we will calculate the stiffness and damping.In the research’s pressure, clearance and hole diameter range, we can provide the best hole-pattern seals’size. It can decrease leakage effectively, make the rotor more stable and cut down the seals’manufacturing cost.