Numerical Prediction of Impact of Clearance on Rotordynamic Coefficients for Labyrinth Brush Seal
-
Yuan Wei
,
Earl H. Dowell
Abstract
The clearance has an obvious influence on the rotordynamic characteristics of brush seals. In order to better know the influence of brush seal on the stability of the rotor bearing system, the rotordynamic coefficients of labyrinth brush seal under different clearance cases and operating conditions are numerically analyzed using CFD RANS solutions coupling with a non-Darcian porous medium model. The results show that at the same geometry parameter the radial force and tangential force will increase when the pressure ratio rises. And when the clearance increases, the direct stiffness decreases sharply at first and then rises slightly. The variation of cross-coupled stiffness is complex. Moreover, at the same operating condition the value of direct damping coefficients increases when clearance increases, which add a stable factor to the rotor.
Funding statement: This research was supported by the National Natural Science Foundation of China (grant no. 11272100, 11672083).
Nomenclature
- O
Support point
- O’
Geometric centers of the disk
- ω
Rotor rotational speed, r/min
- Ω
Whirl velocity, r/min
- e
Rotor eccentricity, mm
- hfh
Fence height, mm
- hbf
Free bristle height, mm
- tb
Thickness of bristle pack, mm
- hur
Upper region height, mm
- cr
Clearance, mm
- Ai
Viscous resistance tensors, m−2
- Bi
Inertial resistance tensors, m−1
- p
Pressure, Pa
- t
Seal cavity axial length, mm
- ΔP
Pressure differential
- Rp
Pressure ratio=pu/pd
- ui
Flow velocity, m/s
- xi
Coordinate direction, m
- ε
Turbulent dissipation
- μ
Molecular viscosity, Pa.s
- ρ
Density of fluid, kg/m3
- K
Direct stiffness, N/mm
- k
Cross-coupled stiffness, N/mm
- C
Direct damping, N·s/mm
- c
Cross-coupled damping, N·s/mm
- i
Spatial coordinate
- u
Upstream
- d
Downstream
- LS
Labyrinth seal
- LBS
Labyrinth brush seal
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© 2019 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Original Research Articles
- Optimization Design and Experimental Study of a Two-disk Rotor System Based on Multi-Island Genetic Algorithm
- Experimental Investigation of the Effect of the Probe Support Tail Structure on the Compressor Cascade Flow Field
- Investigation on Rotor-Labyrinth Seal System with Variable Rotating speed
- Numerical Prediction of Impact of Clearance on Rotordynamic Coefficients for Labyrinth Brush Seal
- CH* Luminance Distribution Application and a One-Dimensional Model of the Supersonic Combustor Heat Release Quantization
- Bleeding Control for Improving Internal Waverider Inlet Self-Starting ability
- Soot Formation and Its Effect in an Aero Gas Turbine Combustor
- Studies on the Effect of Staggering the Rear Rotor in a Counter Rotating Turbine with Respect to Flow and Performance Parameters
- Aerodynamic Performance and Flow Characteristics of an Industrial Centrifugal Blower Volute with Varied Cross-Sectional Shapes/Area Ratios
- CFD Design Study of a Pressure Probe for Centerline Static Pressure Measurement in Supersonic Ejectors
- The Performance of the Self-Supplying Vortex Generator Jets on a High-Speed Compressor Cascade
Articles in the same Issue
- Frontmatter
- Original Research Articles
- Optimization Design and Experimental Study of a Two-disk Rotor System Based on Multi-Island Genetic Algorithm
- Experimental Investigation of the Effect of the Probe Support Tail Structure on the Compressor Cascade Flow Field
- Investigation on Rotor-Labyrinth Seal System with Variable Rotating speed
- Numerical Prediction of Impact of Clearance on Rotordynamic Coefficients for Labyrinth Brush Seal
- CH* Luminance Distribution Application and a One-Dimensional Model of the Supersonic Combustor Heat Release Quantization
- Bleeding Control for Improving Internal Waverider Inlet Self-Starting ability
- Soot Formation and Its Effect in an Aero Gas Turbine Combustor
- Studies on the Effect of Staggering the Rear Rotor in a Counter Rotating Turbine with Respect to Flow and Performance Parameters
- Aerodynamic Performance and Flow Characteristics of an Industrial Centrifugal Blower Volute with Varied Cross-Sectional Shapes/Area Ratios
- CFD Design Study of a Pressure Probe for Centerline Static Pressure Measurement in Supersonic Ejectors
- The Performance of the Self-Supplying Vortex Generator Jets on a High-Speed Compressor Cascade
