Analysis of influencing factors that can cause errors in the application of modern methods of sliding bearing diagnostics in machine and electrical systems

Introduction/purpose: The paper presents the application of modern methods in the diagnostics of sliding bearings and the analysis of influencing factors that can cause errors in such an application. Possibilities to determine with certainty when and where problems affect sliding bearings during system operation are presented. It is also shown how the system will continue to function over time. Causes of failures and the manner of their elimination are predicted, as well as the time for planned maintenance of technical systems. Method: The new method solves the problem of sliding bearing diagnostics by measuring the dynamic trajectories of the sleeve in the sliding bearing and by measuring vibration parameters on the inner and outer surfaces of the technical system. The dynamic trajectories of the bearing sleeve are measured with non-contact probes; therefore, the centering of probes in relation to the geometric center of the bearing is very important. Vibration parameters, directly related to the clearance in the sliding bearing, are measured on the inner and outer surfaces of the system. The choice of vibration parameters and measuring points is very important. This method has a number of advantages over other diagnostic methods, as it is easy to access measuring points. Results: By measuring the dynamic trajectory of the sleeves in the plain bearing and vibration parameters on the inner and outer surfaces, the bearing clearance quantities are determined, including: normal condition, initial clearance size, its further increase, bearing clearance sizes, and the moment when the condition parameters are close to the upper limit of the permissible bearing clearance. Conclusion: New diagnostic methods and monitoring systems can be widely applied to: internal combustion engines, all piston machines, hydroelectric power plants, thermal power plants, processing plants, and many other systems.

Download Full-text

A Review of the Research on the Influencing Factors of Lubrication Performance for Sliding Bearings

Recent Patents on Engineering ◽

10.2174/1872212116666211221104527 ◽

2021 ◽

Vol 16 ◽

Author(s):

Xiaodong Yu ◽

Shiwei Zhan ◽

Dianbin Huang ◽

Fan Sun ◽

Fakun Wang ◽

...

Keyword(s):

Influencing Factors ◽

High Speed ◽

Sliding Friction ◽

Working Environment ◽

Research Progress ◽

Lubricating Oil ◽

Stable Operation ◽

Sliding Bearings ◽

Sliding Bearing ◽

Lubrication Performance

Background: Sliding bearing is a kind of bearing that works under sliding friction, which has the characteristics of stable operation, safety and reliability and noiseless. With the technological progress of the machinery industry, modern machinery and equipment is developing in the direction of high speed and heavy load, its power is getting higher and higher, and the working environment is getting worse, so plain bearings are more and more widely used. Objective: In order to improve the lubricating performance of sliding bearings, the influencing factors of lubricating performance of sliding bearings are summarized and commented. Methods: The research progress and achievements at home and abroad are summarized from three aspects: influencing factors of lubrication performance of radial sliding bearings, thrust sliding bearings and influencing factors of lubricating oil on lubrication performance of sliding bearings, which provides reference for the future development of sliding bearings. Results: The study discusses the experimental method, simulation process and experimental results of the factors affecting the lubrication performance of sliding bearing. Conclusion: The texture, deformation, surface morphology of oil cavity, eccentric load and flow state of sliding bearings all affect the lubricating performance of sliding bearings, and lubricating oil also affects the lubricating performance of sliding bearings.

Download Full-text

THERMAL ANALYSIS OF THE FRICTION PROCESS OF SLIDING BEARINGS USING A STATISTICAL APPROACH

Tribologia ◽

10.5604/01.3001.0010.6991 ◽

2016 ◽

Vol 268 (4) ◽

pp. 157-165 ◽

Cited By ~ 1

Author(s):

Dariusz LEPIARCZYK ◽

Wacław GAWĘDZKI ◽

Jerzy TARNOWSKI

Keyword(s):

Dry Friction ◽

Statistical Approach ◽

Diagnostic Methods ◽

Test Results ◽

Statistical Tools ◽

Sliding Bearings ◽

Sliding Bearing ◽

Friction Process ◽

Tribological System ◽

Complex Phenomena

During the friction processes in a sliding bearing complex, phenomena occur that are included amongst the most difficult and complex problems in tribological studies. Therefore, there is a need for a systematic application of modern diagnostic methods and statistical tools to correctly interpret the operating status of the sliding bearing. The use of these tools is designed to ensure proper operational functioning of the tribological system. The paper presents the test results in the form of thermograms and their subsequent processing with the use of statistical tools. The tests were performed on a laboratory stand with the bearing operating in the presence of a lubricant and with the bearing operating in conditions of technical dry friction. FLIR ResearchIR and STATISTICA software were used for the analysis of the temperature distribution. Final remarks contain the conclusions of the research and recommendations for further study.

Download Full-text

METHODS OF MATHEMATICAL MODELING OF THE COMPRESSION RATIO EFFECT ON THE WORKING PROCESSES IN PRIMARY INTERNAL COMBUSTION ENGINES AS PART OF POWER PLANTS

Производственные технологии будущего: от создания к внедрению. Материалы IV Международной научно-практической конференции ◽

10.17084/978-5-7765-1468-5_2021_283 ◽

2021 ◽

Author(s):

Aleksey Vladimirovich Naumov ◽

Andrey Adievich Malozemov ◽

Nikita Alekseevich Naumov

Keyword(s):

Mathematical Modeling ◽

Compression Ratio ◽

Power Plants ◽

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Engines ◽

Ratio Effect ◽

Working Processes

Download Full-text

Modern methods for assessing morphometric and functional indicators in primary glaucoma

Modern technologies in ophtalmology ◽

10.25276/2312-4911-2021-1-83-87 ◽

2021 ◽

pp. 83-87

Author(s):

N.R. Sharvadze ◽

◽

A.L. Shtilerman ◽

D.P. Skachkov ◽

Y.A. Drovnyak ◽

...

Keyword(s):

Open Angle Glaucoma ◽

Diagnostic Methods ◽

High Tech ◽

Glaucomatous Optic Neuropathy ◽

Static Perimetry ◽

Functional Changes ◽

Modern Methods ◽

Analytical Review ◽

Primary Glaucoma ◽

Key Words Glaucoma

In the article are presented analytical review of scientific articles devoted to the study of modern methods of diagnostics of primary glaucoma. On the basis of scientific articles, a review material was collected and systematized on diagnostic methods for studying morphometric and functional changes in primary glaucoma, which are used in modern ophthalmic practice. In recent years, the improvement and implementation of new high-tech modern diagnostic methods open up new opportunities for researchers and clinicians. Optical coherence tomography, OCT angiography, static perimetry make it possible, by comparing morphometric and functional parameters, to give a more complete, comprehensive assessment of pathological changes in the optic nerve head, in the macular region and at the level of the choriocapillaries. Prevention of glaucoma blindness largely depends on its early diagnosis based on the use of modern organizational and medical technologies. Key words: glaucoma, open-angle glaucoma, intraocular pressure, glaucomatous optic neuropathy, diagnostic methods.

Download Full-text

Modern Methods of Testing Aero-Engines and Power Plants

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100116657 ◽

1950 ◽

Vol 54 (474) ◽

pp. 327-358 ◽

Cited By ~ 3

Author(s):

A. C. Lovesey

Keyword(s):

Power Plants ◽

Test Equipment ◽

Flow Meter ◽

Fuel Flow ◽

Modern Methods ◽

Aero Engine ◽

Aero Engines

In the early days of aero-engines the test equipment was limited to little more than a brake or dynamometer, a fuel flow meter and a few thermometers, and the development of these engines in the direction of better performance and reliability, to a large extent, was an art, built up of experience aided by instinct, of deducing the happenings inside an engine from the few meagre measurements obtainable.Nevertheless, the aero-engine made healthy progress, became more complicated in the process, and introduced many more problems.

Download Full-text

The CFD Design and Optimisation of a 100 kW Hydrogen Fuelled mGT

Volume 8: Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine; Microturbines, Turbochargers, and Small Turbomachines ◽

10.1115/gt2020-14473 ◽

2020 ◽

Author(s):

Cedric Devriese ◽

Gijs Penninx ◽

Guido de Ruiter ◽

Rob Bastiaans ◽

Ward De Paepe

Keyword(s):

Combustion Chamber ◽

Power Plants ◽

Internal Combustion Engines ◽

Cone Angle ◽

Electricity Production ◽

Design Parameters ◽

Inlet Temperature ◽

Large Power ◽

Power Sources ◽

The Impact

Abstract Against the background of a growing deployment of renewable electricity production, like wind and solar, the demand for energy storage will only increase. One of the most promising ways to cover the medium to long-term storage is to use the excess electricity to produce hydrogen via electrolysis. In a modern energy grid, filled with intermittent power sources and ever-increasing problems to construct large power plants in densely populated areas, a network of Decentralised Energy Systems (DES) seems more logical. Therefore, the importance of research into the design of a small to medium-sized hydrogen fuelled micro Gas Turbine (mGT) unit for efficient, local heat and electricity production becomes apparent. To be able to compete with Reciprocating Internal Combustion Engines (RICEs), the mGT needs to reach 40% electrical efficiency. To do so, there are two main challenges; the design of an ultra-low NOX hydrogen combustor and a high Turbine Inlet Temperature (TIT) radial turbine. In this paper, we report on the progress of our work towards that goal. First, an improvement of the initial single-nozzle swirler (swozzle) combustor geometry was abandoned in favour of a full CFD (steady RANS) design and optimisation of a micromix type combustion chamber, due to its advantages towards NOx-emission reduction. Second, a full CFD design and optimisation of the compressor and turbine is performed. The improved micromix combustor geometry resulted in a NOx level reduction of more than 1 order of magnitude compared to our previous swozzle design (from 1400 ppm to 250 ppm). Moreover, several design parameters, such as the position and diameter of the hydrogen injection nozzle and the Air Guiding Panel (AGP) height, have been optimized to improve the flow patterns. Next to the combustion chamber, CFD simulations of the compressor and turbine matched the 1D performance calculations and reached the desired performance goals. A CFD analysis of the impact of the tip gap and exhaust diffuser cone angle led to a choice of these parameters that improved the compressor and turbine performance with a limited loss in efficiency.

Download Full-text

Possibility of using gas lubricant in the cylinders of internal combustion engines of transport vehicles

10.36652/0042-4633-2021-5-13-20 ◽

2021 ◽

pp. 13-20

Author(s):

Keyword(s):

Internal Combustion Engine ◽

Bearing Capacity ◽

Power Plants ◽

Internal Combustion Engines ◽

Combustion Engine ◽

Internal Combustion ◽

Combustion Engines ◽

Engine Piston ◽

Suspension Stiffness ◽

Gas Layer

The prospects of using the gas-static suspension of the internal combustion engine piston in transport vehicles and power plants are considered. The diagram of the piston and the method for calculating the stiffness and bearing capacity of the gas layer surrounding the piston are presented, as well as the results of experiments that showed the relevance of this method. The possibility of gas and static centering of the engine piston is confirmed. Keywords: internal combustion engine, piston, gasstatic suspension, stiffness, bearing capacity, gas medium. [email protected]

Download Full-text

Vibration Parameters Optimization Experiment on Seeder of Rice Bud-Seed for Field Seedling Raising Based on Virtual Prototyping Technology

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.341-342.456 ◽

2013 ◽

Vol 341-342 ◽

pp. 456-461

Author(s):

Wang Yang ◽

Jian Yang ◽

Hui Ruan ◽

Zhao Xin Liang ◽

Jian Lin Mo

Keyword(s):

Influencing Factors ◽

Virtual Prototype ◽

Optimal Combination ◽

Parameters Optimization ◽

Variation Coefficient ◽

Dynamics Simulation ◽

Vibration Velocity ◽

Passing Rate ◽

Velocity Interval ◽

Vibration Parameters

The seeder of rice bud-seed for field seedling raising is a new seedling equipment for field seedling raising, which is a complicated vibration system with multi-freedom. And the effect of the vibration parameters and interactions on the vibration velocity at different locations of the moving rail of two electromagnetic vibration metering devices which are installed side by side is large, and the passing rate of seeding is affected. In this paper, the virtual prototype of seeder of rice bud-seed for field seedling raising is established by ANSYS and ADAMS. The virtual prototype is developed to carry out dynamics simulation by using four-factor quadratic regression orthogonal rotary combination design. Mathematical models of influencing factors of vibration and variation coefficient of vibration velocity, and the factors and average velocity of seeding are established. The factors are optimized. And optimal combination of vibration influencing factors and the variation coefficient of vibration velocity interval with 95% reliability are achieved. The result shows that optimal combination of factors is achieved under the condition that the excitation force amplitude is 39.8N, vibration frequency is 32.7Hz, the velocity is 58.5mm/s, stiffness of vibration isolating rubber pad is 1167N/mm. The corresponding variation coefficient of the vibration velocity is 6.287%, and the average seeding velocity is 18mm/s. The variation coefficient of the vibration velocity interval with 95% reliability is from 2.909% to 9.665%.

Download Full-text

Heat Transfer Analysis of Regenerative Thermo-Mechanical Refrigeration System

ASME 2020 Heat Transfer Summer Conference ◽

10.1115/ht2020-8901 ◽

2020 ◽

Author(s):

Ahmad K. Sleiti ◽

Mohammed Al-Khawaja

Keyword(s):

Environmental Effects ◽

Power Efficiency ◽

Power Plants ◽

Internal Combustion Engines ◽

Waste Heat ◽

Heat Transfer Analysis ◽

Working Fluid ◽

Refrigeration System ◽

Renewable Energy Resources ◽

Working Fluids

Abstract Refrigeration systems contribute to the critical environmental concerns including global warming and ozone depletion. It is necessary to develop new systems that use renewable energy resources and waste heat to perform the cooling function with eco-friendly working fluids. This improves the energy efficiency of the power systems and minimizes the harmful effects of conventional refrigeration systems. This paper introduces an analysis of a regenerative thermo-mechanical refrigeration system that is powered with renewable heat sources (solar, geothermal) or waste heat (from internal combustion engines, gas power plants, and steam power plants). The system operates at the supercritical conditions of the working fluids. The performance of the system is evaluated based on power efficiency, the COP, and the expander-compressor diameters. Also, a number of working fluids were compared with each other based on their performance and environmental effects. There is a trade-off between high-performance fluids and their environmental effects. Using R32 as a working fluid at Th = 150 °C and Tc1 = 40 °C, the system produces a cooling capacity of 1 kW with power efficiency of 10.23%, expander diameter of 53.12 mm and compressor diameter of 75.4mm. The regenerator increases the power efficiency by about 1%. However, the size of the regenerator is small (Dr = 6.5 mm, Lr = 142 mm].

Download Full-text