Brush seal wear model

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.

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Simulation and Experimental Study on Wear of U-Shaped Rings of Power Connection Fittings under Strong Wind Environment

Materials ◽

10.3390/ma14040735 ◽

2021 ◽

Vol 14 (4) ◽

pp. 735

Author(s):

Songchen Wang ◽

Xianchen Yang ◽

Xinmei Li ◽

Cheng Chai ◽

Gen Wang ◽

...

Keyword(s):

Abrasive Wear ◽

Adhesive Wear ◽

Surface Hardness ◽

Wear Depth ◽

Strong Wind ◽

Wear Model ◽

Wind Environment ◽

Simulation Results ◽

Oxidation Wear ◽

Good Agreement

The objective of this study was to investigate the wear characteristics of the U-shaped rings of power connection fittings, and to construct a wear failure prediction model of U-shaped rings in strong wind environments. First, the wear evolution and failure mechanism of U-shaped rings with different wear loads were studied by using a swinging wear tester. Then, based on the Archard wear model, the U-shaped ring wear was dynamically simulated in ABAQUS, via the Umeshmotion subroutine. The results indicated that the wear load has an important effect on the wear of the U-shaped ring. As the wear load increases, the surface hardness decreases, while plastic deformation layers increase. Furthermore, the wear mechanism transforms from adhesive wear, slight abrasive wear, and slight oxidation wear, to serious adhesive wear, abrasive wear, and oxidation wear with the increase of wear load. As plastic flow progresses, the dislocation density in ferrite increases, leading to dislocation plugs and cementite fractures. The simulation results of wear depth were in good agreement with the test value of, with an error of 1.56%.

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Research on the wear model of carbon/carbon composite finger seal

Wear ◽

10.1016/j.wear.2021.203682 ◽

2021 ◽

pp. 203682

Author(s):

Hua Su ◽

Chuding Zhang ◽

Shan Sun

Keyword(s):

Carbon Composite ◽

Wear Model

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A First Step towards a Tribological Approach to Investigate Cutting Tool Wear

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.611-612.452 ◽

2014 ◽

Vol 611-612 ◽

pp. 452-459 ◽

Cited By ~ 1

Author(s):

Giovenco Axel ◽

Frédéric Valiorgue ◽

Cédric Courbon ◽

Joël Rech ◽

Ugo Masciantonio

Keyword(s):

Tool Wear ◽

Cutting Tool ◽

304L Stainless Steel ◽

Fe Modelling ◽

Wear Model ◽

Cutting Tool Wear ◽

The Will ◽

Preliminary Study ◽

The Impact ◽

Macroscopic Parameters

The present work is motivated by the will to improve Finite Element (FE) Modelling of cutting tool wear. As a ﬁrst step, the characterisation of wear mechanisms and identiﬁcation of a wear model appear to be fundamental. The key idea of this work consists in using a dedicated tribometer, able to simulate relevant tribological conditions encountered in cutting (pressure, velocity). The tribometer can be used to estimate the evolution of wear versus time for various tribological conditions (pressure, velocity, temperature). Based on this design of experiments, it becomes possible to identify analytically a wear model. As a preliminary study this paper will be focused on the impact of sliding speed at the contact interface between 304L stainless steel and tungsten carbide (WC) coated with titanium nitride (TiN) pin. This experiment enables to observe a modiﬁcation of wear phenomena between sliding speeds of 60 m/min and 180 m/min. Finally, the impact on macroscopic parameters has been observed.

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Computed Effects of Rotor-Induced Swirl on Brush Seal Performance—Part 2: Bristle Force Analysis

Journal of Tribology ◽

10.1115/1.2831629 ◽

1996 ◽

Vol 118 (4) ◽

pp. 920-926 ◽

Cited By ~ 12

Author(s):

M. C. Sharatchandra ◽

D. L. Rhode

Keyword(s):

Inclination Angle ◽

Flow Direction ◽

Flow Simulation ◽

Companion Paper ◽

Navier Stokes ◽

Brush Seal ◽

Swirl Flows ◽

Lift Off ◽

Square Configuration ◽

Periodic Module

This paper analytically investigates the aerodynamic bristle force distributions in brush seals used in aircraft gas turbine engines. These forces are responsible for the onset of bristle tip lift-off from the rotor surface which significantly affects brush seal performance. In order to provide an enhanced understanding of the mechanisms governing the bristle force distributions, a full Navier-Stokes flow simulation is performed in a streamwise periodic module of bristles corresponding to the staggered square configuration. As is the case with a companion paper (Sharatchandra and Rhode, 1996), this study has the novel feature of considering the combined effects of axial (leakage) and tangential (swirl) flows. Specifically, the effects of intra-bristle spacing and bristle inclination angle are explored. The results indicate that the lifting bristle force increases with reduced intra-bristle spacing and increased inclination angle. It was also observed that increases in the axial or tangential flow rates increased the force component in the normal as well as the flow direction.

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Wear Model for Piston Ring and Cylinder Bore System

ASME 2005 Internal Combustion Engine Division Fall Technical Conference (ICEF2005) ◽

10.1115/icef2005-1340 ◽

2005 ◽

Cited By ~ 1

Author(s):

Yunchao Qiu ◽

Qian Zou ◽

Gary C. Barber ◽

Harold E. McCormick ◽

Dequan Zou ◽

...

Keyword(s):

Piston Ring ◽

Thickness Distribution ◽

Matrix Ring ◽

Experimental Investigations ◽

General Tendency ◽

Wear Model ◽

Wear Process ◽

The Matrix ◽

Surface Profiles ◽

Cylinder Bore

A new wear model for piston ring and cylinder bore system has been developed to predict wear process with high accuracy and efficiency. It will save time and cost compared with experimental investigations. Surfaces of ring and bore were divided into small domains and assigned to corresponding elements in two-dimensional matrix. Fast Fourier Transform (FFT) and Conjugate Gradient Method (CGM) were applied to obtain pressure distribution on the computing domain. The pressure and film thickness distribution were provided by a previously developed ring/bore lubrication module. By changing the wear coefficients of the ring and bore with accumulated cycles, wear was calculated point by point in the matrix. Ring and bore surface profiles were modified when wear occurred. The results of ring and bore wear after 1 cycle, 10 cycles and 2 hours at 3600 rpm were calculated. They coincided well with the general tendency of wear in a ring and bore system.

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