Influence of Geometry on Rotordynamic Coefficients of Brush Seal
-
Yuan Wei
,
Yinghou Jiao
Abstract
It has been observed that the geometry of a brush seal has a significant effect on the sealing performance. However, the relationship between rotordynamic coefficients and geometry factors of the brush seal itself are rarely considered. In this article, the rotordynamic coefficients of a typical single-stage brush seal for different geometries and operating conditions were numerically analyzed using CFD RANS solutions coupled with a non-Darcian porous medium model. The reaction force which plays an essential role in rotordynamic coefficients was obtained by integrating the dynamic pressure distribution. The influence of the bristle pack thickness, fence height, clearance size and other working condition parameters on aerodynamic force, stiffness coefficients, and damping coefficients of brush seal were presented and compared. In addition, the effects of various geometric configurations on pressure and flow features were also discussed.
Funding statement: Funding: The research is supported by National Natural Science Foundation of China (Grant No. 11272100).
Nomenclature
- ω
rotational speed, r/min
- Ω
whirl velocity, r/min
- e
eccentricity, mm
- hfh
frence height, mm
- hbf
free bristle height, mm
- tb
thickness of bristle pack, mm
- cr
clearance, mm
- d
bristle diameter, mm
- Ai
viscous resistance tensors, m–2
- Bi
inertial resistance tensors, m–1
- ε
porosity of bristle pack
- n
bristle pack density, bristles/m
- p
pressure, Pa
- ΔP
pressure differential
- Rp
pressure ratio = pu / pd
- ui
velocity, m/s
- xi
coordinate direction, m
- μ
molecular viscosity, Pa.s
- ρ
density of fluid, Kg/m3
- K
direct stiffness, N/m
- k
cross-coupled stiffness, N/m
- C
direct damping, N·s/m
- c
cross-coupled damping, N·s/m
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Articles in the same Issue
- Frontmatter
- Study of Decay Characteristics of Hexagonal and Square Supersonic Jet
- Investigation on the Film Cooling Performance of Diffuser Shaped Holes with Different Inclination Angles
- Model-based Acceleration Control of Turbofan Engines with a Hammerstein-Wiener Representation
- Fatigue Life Prediction of Low Pressure Turbine Shaft of Turbojet Engine
- Influence of Geometry on Rotordynamic Coefficients of Brush Seal
- Numerical Investigation of Transient Flow in a Prototype Centrifugal Pump during Startup Period
- Thrust Performance Evaluation of a Turbofan Engine Based on Exergetic Approach and Thrust Management in Aircraft
- Real-time Simulation of Turboprop Engine Control System
- Ignition Study on a Rotary-valved Air-breathing Pulse Detonation Engine
Articles in the same Issue
- Frontmatter
- Study of Decay Characteristics of Hexagonal and Square Supersonic Jet
- Investigation on the Film Cooling Performance of Diffuser Shaped Holes with Different Inclination Angles
- Model-based Acceleration Control of Turbofan Engines with a Hammerstein-Wiener Representation
- Fatigue Life Prediction of Low Pressure Turbine Shaft of Turbojet Engine
- Influence of Geometry on Rotordynamic Coefficients of Brush Seal
- Numerical Investigation of Transient Flow in a Prototype Centrifugal Pump during Startup Period
- Thrust Performance Evaluation of a Turbofan Engine Based on Exergetic Approach and Thrust Management in Aircraft
- Real-time Simulation of Turboprop Engine Control System
- Ignition Study on a Rotary-valved Air-breathing Pulse Detonation Engine
