Performance analysis of thrust pad bearing using micro-rectangular pocket and bionic texture

2020 ◽  
pp. 135065012094007
Author(s):  
JC Atwal ◽  
RK Pandey
Keyword(s):  
Friction Coefficient ◽  
Performance Analysis ◽  
Thrust Bearing ◽  
Labeo Rohita ◽  
The Other ◽  
Fish Scale ◽  
Performance Parameters ◽  
Texture Parameters ◽  
Minimum Film Thickness ◽  
Thrust Pad

This paper presents the performance behaviors of a hydrodynamic thrust bearing incorporating new pad surface designs involving microrectangular pocket and Labeo rohita fish scale texture. The bearing performance parameters have been numerically explored and analyzed using three different pad surface designs. The effects of texture parameters such as pocket/texture depth, extend of pocket, and fish texture spread in the circumferential and radial directions, the number of scale texture waves in circumferential and radial directions, have been investigated for improving the performance of the bearing. It has been found that the pad surface having microrectangular pocket and fish scale texture together yields substantial increase in minimum film thickness and reduction in friction coefficient as compared to the other pad designs.

Numerical Calculation Analysis of Structural Parameters of Water-Lubricated Thrust Bearing

2010 ◽  
Vol 44-47 ◽  
pp. 1666-1671 ◽  
Author(s):  
Lin Liu Zheng ◽  
Zhu Xin Wu
Keyword(s):  
Friction Coefficient ◽  
Film Thickness ◽  
Thrust Bearing ◽  
Structural Parameters ◽  
Water Film ◽  
Film Pressure ◽  
Water Film Thickness ◽  
Coefficient Increase ◽  
Maximum Water ◽  
Thrust Pad

The affect of the thrust pad inclination and ratio of length to breadth (L/B) on the lubricity of a water-lubricated thrust bearing is studied in numerical method. The research results indicate that when the elastic deformation is considered, the distribution of both water film thickness and pressure presents to be paraboloid. With the increase of thrust pad inclination, both maximum water-film pressure and the friction coefficient increase, and the minimum water-film thickness decreases first and then increases; when the L/B increases in the range of 1~2, both maximum water-film pressure and the friction coefficient increase, but the minimum water-film thickness decreases.

Comparison of Nano-second and Millisecond Pulse Generators for Biological applications of Electroporation

2021 ◽  
pp. 2843-2851
Author(s):  
Apoorwa Haldiyan ◽  
Debarshi Ghosh ◽  
Nitin Saluja ◽  
Selvakumar Ganeshan ◽  
Gurjeet Singh Thakur
Keyword(s):  
Solid State ◽  
Performance Analysis ◽  
Cell Biology ◽  
Experimental Models ◽  
The Other ◽  
Power Electronic ◽  
Biological Applications ◽  
Performance Parameters ◽  
Pulse Generators ◽  
Millisecond Pulse

A phenomenon that transiently increases the permeability of the cells is known as electroporation. It is the basis for number of the applications in biomedical domains. It is essential to consider requirement of high precision and the overall size of electroporator. The recent decades have seen the development of solid-state power electronic modules. The modules enable generation of high voltage millisecond and nano-second pulses with options to reduce the overall size of the equipment. The selective modules are verified with experimental models and available for commercial usage. While the other modules are still undergoing optimization processes. The generator generates pulses for varying performances. Hence, this paper presents knowledge for different nanosecond and millisecond pulse generating circuits for electroporation purposes. The performance parameters like the width of the pulse, its amplitude are compared for different circuit topologies. The performance analysis of different topologies and their impact on the performance of the electroporation at the cell biology level are considered in this paper.

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.

Influence of new surface micro-structures on the performance behaviours of fluid film tilting pad thrust bearings

2021 ◽  
pp. 095440622110309
Author(s):  
JC Atwal ◽  
RK Pandey
Keyword(s):  
Mass Conservation ◽  
Performance Parameters ◽  
Algebraic Equations ◽  
The Finite Element Method ◽  
Thrust Bearings ◽  
Lubrication Equation ◽  
Tilting Pad ◽  
Minimum Film Thickness ◽  
Newton Raphson ◽  
Micro Structures

Performance parameters such as power loss, minimum film thickness, and maximum oil temperature of the sector-shaped tilting pad thrust bearings employing the new micro-structural geometries on pad surfaces have been investigated. The lubrication equation incorporating the mass-conservation issue is discretized using the finite element method and the solution of resulting algebraic equations is obtained employing a Newton-Schur method. The pad equilibrium in the analysis is established using the Newton-Raphson and Braydon methods. The influence of attributes of micro-structures such as depth, circumferential and radial positioning extents have been explored on the performance behaviours. It is found that with the new micro-structured pad surfaces, the performance parameters significantly improved in comparison to conventional plain and conventional rectangular pocketed pads.

scholarly journals Analysis of High-Friction Surface Texture with Respect to Friction and Wear

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 758
Author(s):  
Cibi Pranav ◽  
Minh-Tan Do ◽  
Yi-Chang Tsai
Keyword(s):  
Friction Coefficient ◽  
Surface Texture ◽  
Safety Concern ◽  
Future Research ◽  
Scanning System ◽  
Novel Approach ◽  
Texture Parameters ◽  
Aggregate Loss ◽  
Friction Surfaces ◽  
The Impact

High Friction Surfaces (HFS) are applied to increase friction capacity on critical roadway sections, such as horizontal curves. HFS friction deterioration on these sections is a safety concern. This study deals with characterization of the aggregate loss, one of the main failure mechanisms of HFS, using texture parameters to study its relationship with friction. Tests are conducted on selected HFS spots with different aggregate loss severity levels at the National Center for Asphalt Technology (NCAT) Test Track. Friction tests are performed using a Dynamic Friction Tester (DFT). The surface texture is measured by means of a high-resolution 3D pavement scanning system (0.025 mm vertical resolution). Texture data are processed and analyzed by means of the MountainsMap software. The correlations between the DFT friction coefficient and the texture parameters confirm the impact of change in aggregates’ characteristics (including height, shape, and material volume) on friction. A novel approach to detect the HFS friction coefficient transition based on aggregate loss, inspired by previous works on the tribology of coatings, is proposed. Using the proposed approach, preliminary outcomes show it is possible to observe the rapid friction coefficient transition, similar to observations at NCAT. Perspectives for future research are presented and discussed.

Fabrication and Characterization of pH-Mediated Labeo rohita Fish Scale Extract Capped Silver Nanoparticles and its Antibacterial Activity

2021 ◽  
Author(s):  
Gattu Sampath ◽  
Douglas J. H. Shyu ◽  
Neelamegam Rameshkumar ◽  
Muthukalingan Krishnan ◽  
Kaliannan Durairaj ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Labeo Rohita ◽  
Fish Scale ◽  
Fabrication And Characterization

An Accurate Solution of the Gas Lubricated, Flat Sector Thrust Bearing

1977 ◽  
Vol 99 (1) ◽  
pp. 82-88 ◽  
Author(s):  
I. Etsion ◽  
D. P. Fleming
Keyword(s):  
Film Thickness ◽  
Thrust Bearing ◽  
Load Capacity ◽  
Thickness Distribution ◽  
Maximum Load ◽  
Accurate Solution ◽  
Operating Conditions ◽  
Thrust Bearings ◽  
Practical Design ◽  
Minimum Film Thickness

A flat sector shaped pad geometry for gas lubricated thrust bearings is analyzed considering both pitch and roll angles of the pad and the true film thickness distribution. Maximum load capacity is achieved when the pad is tilted so as to create a uniform minimum film thickness along the pad trailing edge. Performance characteristics for various geometries and operating conditions of gas thrust bearings are presented in the form of design curves. A comparison is made with the rectangular slider approximation. It is found that this approximation is unsafe for practical design, since it always overestimates load capacity.

scholarly journals Optimized Traffic Grooming through modified PSO based Iterative Hungarian algorithm in Optical Networks

2021 ◽  
Vol 50 (3) ◽  
pp. 546-557
Author(s):  
J. KUMARNATH ◽  
K. BATRI
Keyword(s):  
Performance Analysis ◽  
Optical Networks ◽  
Performance Measures ◽  
Shortest Path ◽  
Optical Network ◽  
Traffic Grooming ◽  
Pso Algorithm ◽  
Propagation Delay ◽  
The Other ◽  
Modified Pso

Due to huge size of the data and quick transmission of data between the nodes present in the optical network, a condition of network traffic is created among the nodes of the network. This issue of traffic can be overcome by employing numerous traffic grooming techniques. In this research paper, the best suitable shortest path is determined by the multi objective modified PSO algorithm and an innovative visibility graph based Iterative Hungarian Traffic grooming algorithm is implemented to reduce the blocking ratio through improving the allocation of bandwidth between the users. Then finally the performance analysis is carried out by means of performance measures such as traffic throughput, transceivers count, average propagation delay, blocking ratio, and success ratio. It can be inferred that the proposed work obtains enhanced outcomes when compared to the other existing techniques.

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