Numerical Analysis of Pressure Distribution in a Brush Seal based on a 2-D Staggered Tube Banks Model

2019 ◽  
pp. -1--1
Author(s):  
Yuchi Kang ◽  
Meihong Liu ◽  
Sharon Kao-Walter ◽  
Jinbin Liu ◽  
Qihong Ceng
Keyword(s):  
Numerical Analysis ◽  
Pressure Distribution ◽  
Brush Seal ◽  
Tube Banks

scholarly journals Numerical Analysis of Flow across Brush Elements Based on a 2-D Staggered Tube Banks Model

Aerospace ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 19
Author(s):  
Xiaolei Song ◽  
Meihong Liu ◽  
Xiangping Hu ◽  
Xueliang Wang ◽  
Taohong Liao ◽  
...  
Keyword(s):  
Euler Number ◽  
Dynamic Pressure ◽  
Labyrinth Seals ◽  
System A ◽  
Brush Seal ◽  
Back Plate ◽  
Computational Fluid Dynamics Cfd ◽  
Secondary Air ◽  
Tube Banks ◽  
Gas Expansion

In order to improve efficiency in turbomachinery, brush seal replaces labyrinth seals widely in the secondary air system. A 2-d staggered tube bank model is adopted to simulate the gas states and the pressure character in brush seal, and computational fluid dynamics (CFD) is used to solve the model in this paper. According to the simulation results, the corrected formula of the Euler number and dimensionless pressure are given. The results show that gas expands when flow through the bristle pack, and the gas expansion closes to an isotherm process. The dynamic pressure increases with decreasing static pressure. The Euler number can reflect the seal performance of brush seals in leakage characteristics. Compared with increasing the number of rows, the reduction of the gap is a higher-efficiency method to increase the Euler number. The Euler number continually increases as the gap decreases. However, with the differential pressure increasing, Euler number first increases and then decreases as the number of rows increases. Finally, the pressure distribution on the surface of end rows is asymmetric, and it may increase the friction between the bristles and the back plate.

The Numerical Analysis of the Velocity and Pressure Distribution of the Oil Film in Heavy Hydrostatic Thrust Bearing

2014 ◽  
Vol 541-542 ◽  
pp. 658-662
Author(s):  
Jian Li ◽  
Yuan Chen ◽  
Yang Chun Yu ◽  
Zhu Xin Tian ◽  
Yu Huang
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Pressure Distribution ◽  
Working Conditions ◽  
Thrust Bearing ◽  
Rotation Speed ◽  
The Other ◽  
Surface Load ◽  
Oil Film ◽  
Volume Method

To study the velocity and pressure distribution of the oil film in a heavy hydrostatic thrust bearing, a mathematical model of the velocity is proposed and the finite volume method (FVM) has been used to simulate the flow field under different working conditions. Some pressure experiments were carried out and the results verified the correctness of the simulation. It is concluded that the pressure distribution varies small under different rotation speed when the surface load on the workbench is constant. But the velocity of the oil film is influenced greatly by the rotation speed. When the rotation speed of the workbench is as quick as enough, the velocity of the oil film on one radial side of the pad will be zero, that is to say the lubrication oil will be drained from the other three sides of the recess.

scholarly journals An Iterative CFD and Mechanical Brush Seal Model and Comparison With Experimental Results

1998 ◽  
Author(s):  
L. H. Chen ◽  
P. E. Wood ◽  
T. V. Jones ◽  
J. W. Chew
Keyword(s):  
Pressure Distribution ◽  
Mechanical Model ◽  
Experimental Results ◽  
Iterative Technique ◽  
Mechanical Part ◽  
Contact Loads ◽  
Brush Seal ◽  
Mass Flows ◽  
Frictional Effects

The position of the bristles within a brush seal is dictated by the pressure distribution within the seal, which is itself influenced by the position of the bristle matrix. In order to predict mass flows, pressure capabilities, bristle displacements, stresses and contact loads at the rotor interface a technique for iterating between a CFD and a mechanical model has been developed. The iterative technique is used to model the behaviour of seals with an initial build clearance, where the application of pressure causes a change in the position of the bristle matrix. Frictional effects between neighbouring bristles and at the backing ring influence the behaviour of the bristles and these are accounted for within the mechanical part of the model. Results are presented and discussed for seals of both initial build clearance and interference. The mathematical predictions for flow, contact loads at the rotor interface and the nature of the bristles displacements are compared with experimental results.

A Numerical Analysis for the Transient EHL Process of a Cam-Tappet Pair in I. C. Engine

1989 ◽  
Vol 111 (3) ◽  
pp. 413-417 ◽  
Author(s):  
Xiaolan Ai ◽  
Haiqing Yu
Keyword(s):  
Numerical Analysis ◽  
Pressure Distribution ◽  
Numerical Method ◽  
Rotation Angle ◽  
Elastohydrodynamic Lubrication ◽  
Surface Failure ◽  
Lubrication Conditions ◽  
Film Profile

The transient elastohydrodynamic lubrication (EHL) process of cam-tappet pair in I. C. engine is analyzed with a full numerical method. The variations of pressure distribution and film profile as a function of rotation angle of cam shaft provide useful information in evaluating lubrication conditions as well as analyzing failures of contacting surfaces. Results show that the segment in cam contour from φ = 30 to φ = 110 deg is a difficult lubrication range, and surface failure may occur first in this range. This statement was confirmed by preliminary exprimental work conducted in a testing rig.

Experimental and Numerical Analysis of the Secondary Flow Across the Interphase Balance Drum of a High Pressure Back-to-Back Centrifugal Compressor

2017 ◽  
Author(s):  
Carmine Carmicino ◽  
Francesco Maiuolo ◽  
Emanuele Rizzo
Keyword(s):  
Experimental Data ◽  
High Pressure ◽  
Numerical Analysis ◽  
Pressure Distribution ◽  
Centrifugal Compressor ◽  
Operating Conditions ◽  
Local Pressure ◽  
Flow Angle ◽  
One Dimensional ◽  
Honeycomb Seal

With the major aim of gathering information on the machine lateral stability in high pressure-high density conditions, and of assessing the prediction capabilities of the in-house design tools and overall process, a back-to-back centrifugal compressor has been instrumented and tested in several operating conditions. The present paper focuses on the secondary flows across the interphase balance drum of the back-to-back compressor, where the sealing is accomplished with a honeycomb seal. The compressor interphase section has been instrumented with dedicated special probes for the clearance measurement associated to pressure and flow angle probes in order to characterize pressure distributions and swirl variations depending on the specific operating range. The experimental data acquired over the machine operation have been compared with a three-dimensional steady-state numerical analysis results obtained from the simulation, carried out with a Reynolds averaged Navier-Stokes (RANS) approach, of the flowfield in the complex interphase secondary system composed by the impeller cavities and the honeycomb seal. This paper addresses the comparison between numerical results and experimental data, which allowed the matching of models with experiments in terms of pressure distribution and the complex flowfield. Finally, all the data have been used to validate an in-house one-dimensional flow network solver for pressure distribution and leakage flow calculations along cavities and seals. Results have shown a general good agreement between measured data and calculation output. In particular, computational fluid dynamic analysis provided detailed pressure and velocity distributions that allowed gaining insight in the physics of such a complex region. The one-dimensional model has been demonstrated to be a fast and reliable tool to well predict local pressure variations inside cavities and seals and, consequently, the residual axial thrust.

Aerodynamic characteristics of a two-dimensional porous sail

1989 ◽  
Vol 206 ◽  
pp. 463-475 ◽  
Author(s):  
S. Murata ◽  
S. Tanaka
Keyword(s):  
Numerical Analysis ◽  
Pressure Distribution ◽  
Dynamic Stability ◽  
Jacobi Polynomials ◽  
Angle Of Attack ◽  
Leading Edge ◽  
Aerodynamic Characteristics ◽  
Two Dimensional ◽  
Centre Of Pressure ◽  
Edge Conditions

A method is presented for the numerical analysis of the aerodynamic characteristics of a two-dimensional single-surface porous sail. In this analysis the authors apply a series of Jacobi polynomials to express the pressure distribution and chordwise shape, considering carefully leading-edge conditions. It is found that the aero-dynamic stability of a sail increases with increasing porosity. The effects of porosity on the value of the life coefficient and the position of the centre of pressure are shown in diagrams as functions of angle of attack and of excess length of membrane over the chord length.

An Iterative CFD and Mechanical Brush Seal Model and Comparison With Experimental Results

1999 ◽  
Vol 121 (4) ◽  
pp. 656-662 ◽  
Author(s):  
L. H. Chen ◽  
P. E. Wood ◽  
T. V. Jones ◽  
J. W. Chew
Keyword(s):  
Pressure Distribution ◽  
Mechanical Model ◽  
Experimental Results ◽  
Iterative Technique ◽  
Mechanical Part ◽  
Contact Loads ◽  
Brush Seal ◽  
Mass Flows ◽  
Frictional Effects

The position of the bristles within a brush seal is dictated by the pressure distribution within the seal, which is itself influenced by the position of the bristle matrix. In order to predict mass flows, pressure capabilities, bristle displacements, stresses, and contact loads at the rotor interface, a technique for iterating between a CFD and a mechanical model has been developed. The iterative technique is used to model the behavior of seals with an initial build clearance, where the application of pressure causes a change in the position of the bristle matrix. Frictional effects between neighboring bristles and at the backing ring influence the behavior of the bristles and these are accounted for within the mechanical part of the model. Results are presented and discussed for seals of both initial build clearance and interference. The mathematical predictions for flow, contact loads at the rotor interface, and the nature of the bristles displacements are compared with experimental results.

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