A novel wear angle determination algorithm for wear image based on direction correlation of wear scar

A lubricant is a substance that lessens friction and wear between mechanical parts. A good quality lubricating oil is required for protecting the mechanical equipment and reducing energy consumption. Its performance index (friction coefficient) could be measured by the four-ball wear test. For the morphological analysis of testing data from the four-ball wear test, determination of wear angle is very important for measuring the wear spot diameter, validity of the four-ball wear test and recognition of abnormal wear scar. On the basis of character analysis and image processing technology, a novel wear angle determination algorithm for wear scar is presented in this article. The direction of the wear scar (wear angle) is determined based on angle transformation and grey consistency (the smallest change of grey level). Simulation results show that the algorithm has high precision, good robustness and less time consuming. The average absolute error of our method is 0.8° and the absolute error of 95% of samples is <4°. The average runtime per frame is 3.896 s in the simulation platform.

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Correlation study of fuel injection strategies on engine emission and lubricating oil performance

E3S Web of Conferences ◽

10.1051/e3sconf/202126801008 ◽

2021 ◽

Vol 268 ◽

pp. 01008

Author(s):

Chuanqi Wang ◽

Guotian Li ◽

Enxing Zhang ◽

Zenghui Yin ◽

Jing Hao

Keyword(s):

Kinematic Viscosity ◽

Fuel Injection ◽

Correlation Study ◽

Lubricating Oil ◽

Injection Timing ◽

Gas Temperature ◽

Spot Diameter ◽

Wear Spot ◽

Wear Spot Diameter ◽

Injection Strategies

Based on different fuel injection strategies, this paper analyzes the factors such as engine original emission smoke, exhaust temperature, soot content, wear spot diameter and kinematic viscosity. The study found that delaying injection timing, increased afterburn, engine original soot emissions, exhaust gas temperature increase, but will increase the thermal load of the parts. At the same time, the growth rate of lubricant soot and kinematic viscosity increased; The wear spot diameter at the same soot content is reduced, and the wear is reduced. In the end, the paper finally selects 1°CA BTDC as the optimal fuel injection strategy to achieve rapid aging of engine lubricating oil in order to complete the assessment of the anti-wear performance of lubricating oil.

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A Multimethod Analysis for Average Annual Precipitation Mapping in the Khorasan Razavi Province (Northeastern Iran)

Atmosphere ◽

10.3390/atmos12050592 ◽

2021 ◽

Vol 12 (5) ◽

pp. 592

Author(s):

Mehdi Aalijahan ◽

Azra Khosravichenar

Keyword(s):

Regional Planning ◽

Interpolation Method ◽

Absolute Error ◽

Rain Gauge ◽

Annual Precipitation ◽

Coefficient Of Determination ◽

Distance Weighting ◽

Average Annual Precipitation ◽

Inverse Distance

The spatial distribution of precipitation is one of the most important climatic variables used in geographic and environmental studies. However, when there is a lack of full coverage of meteorological stations, precipitation estimations are necessary to interpolate precipitation for larger areas. The purpose of this research was to find the best interpolation method for precipitation mapping in the partly densely populated Khorasan Razavi province of northeastern Iran. To achieve this, we compared five methods by applying average precipitation data from 97 rain gauge stations in that province for a period of 20 years (1994–2014): Inverse Distance Weighting, Radial Basis Functions (Completely Regularized Spline, Spline with Tension, Multiquadric, Inverse Multiquadric, Thin Plate Spline), Kriging (Simple, Ordinary, Universal), Co-Kriging (Simple, Ordinary, Universal) with an auxiliary elevation parameter, and non-linear Regression. Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and the Coefficient of Determination (R2) were used to determine the best-performing method of precipitation interpolation. Our study shows that Ordinary Co-Kriging with an auxiliary elevation parameter was the best method for determining the distribution of annual precipitation for this region, showing the highest coefficient of determination of 0.46% between estimated and observed values. Therefore, the application of this method of precipitation mapping would form a mandatory base for regional planning and policy making in the arid to semi-arid Khorasan Razavi province during the future.

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Determination of Gas Well Deliverability in Volcanic Gas Reservoir Using Transient Testing Data

10.2118/114916-ms ◽

2008 ◽

Author(s):

Qinglong Xu ◽

Rui Shao ◽

Shiquan Yu ◽

Baizhou Fu

Keyword(s):

Volcanic Gas ◽

Gas Reservoir ◽

Gas Well ◽

Testing Data

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Determination of Steady-State Adhesive Wear Rate

World Tribology Congress III, Volume 1 ◽

10.1115/wtc2005-63900 ◽

2005 ◽

Cited By ~ 1

Author(s):

L. J. Yang

Keyword(s):

Steady State ◽

Wear Rate ◽

Wear Test ◽

Standard Test ◽

Test Method ◽

Testing Time ◽

Wear Coefficient ◽

Wear Rates ◽

Test Methodology

Wear rates obtained from different investigators could vary significantly due to lack of a standard test method. A test methodology is therefore proposed in this paper to enable the steady-state wear rate to be determined more accurately, consistently, and efficiently. The wear test will be divided into four stages: (i) to conduct the transient wear test; (ii) to predict the steady-state wear coefficient with the required sliding distance based on the transient wear data by using Yang’s second wear coefficient equation; (iii) to conduct confirmation runs to obtain the measured steady-state wear coefficient value; and (iv) to convert the steady-state wear coefficient value into a steady-state wear rate. The proposed methodology is supported by wear data obtained previously on aluminium based matrix composite materials. It is capable of giving more accurate steady-state wear coefficient and wear rate values, as well as saving a lot of testing time and labour, by reducing the number of trial runs required to achieve the steady-state wear condition.

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Determination of zinc in lubricating oils and lubricating oil concentrates

Fresenius Zeitschrift für Analytische Chemie ◽

10.1007/bf00518156 ◽

1968 ◽

Vol 239 (1) ◽

pp. 33-36 ◽

Cited By ~ 4

Author(s):

K. S. Anand ◽

Prabhu Dayal ◽

O. N. Anand

Keyword(s):

Lubricating Oil ◽

Lubricating Oils

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On the determination of the internal pressure in a cylinder based on acoustic testing data

Russian Journal of Nondestructive Testing ◽

10.1134/s1061830914100106 ◽

2014 ◽

Vol 50 (10) ◽

pp. 595-601 ◽

Cited By ~ 5

Author(s):

A. O. Vatul’yan ◽

V. V. Dudarev

Keyword(s):

Internal Pressure ◽

Testing Data ◽

Acoustic Testing

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On the precise measurement capability of the direct microscopic measurement method for wear volume characterization

MATEC Web of Conferences ◽

10.1051/matecconf/201818802007 ◽

2018 ◽

Vol 188 ◽

pp. 02007

Author(s):

Enbiya Türedi

Keyword(s):

Normal Load ◽

Wear Test ◽

Optical Microscope ◽

Bearing Steel ◽

Wear Scar ◽

Wear Volume ◽

Measurement Capability ◽

Comparison Results ◽

Novel Method ◽

Microscopic Measurement

There are plenty of methods for determining the wear volume after a wear test. Due to the geometrical assumptions, some of them could unfortunately lead to mistaken results. It has been shown that a novel method, the direct microscopic measurement, is able to calculate the wear volume on a specimen surface very precisely and accurately [1-2]. It is based on creating a series of line profiles perpendicular to the wear scar. This novel method, however, needs to be characterized in terms of measurement limitations and minimum detectable volume capability. For example, how small or how shallow a wear scar could be calculated or measured with this method, must be determined. For this purpose, it has been prepared a series of wear test specimens exposed to the different amounts of wear in a “pin-on-disk” type test rig. As specimens, two different non-ferrous mold materials, Al bronze alloys, were selected and prepared metallographically. Counterpart materials were inox steel and bearing steel balls with diameter of 6 mm. Normal load was set to 5 N. Test configurations were set to 1, 5, 10 and 100 m of sliding distance values, in turn. Wear tests were conducted in according to ASTM G99 standard. Wear volume results were determined both direct microscopic measurement and also a 3D optical microscope methods. Comparison results showed that the novel method could be successfully used for wear volume calculations even with small amounts of wear volume conditions.

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