Wheel-Rail Contact Characteristics on a Tangent Track Vs a Roller Rig

ASME 2012 Rail Transportation Division Fall Technical Conference ◽

10.1115/rtdf2012-9406 ◽

2012 ◽

Cited By ~ 2

Author(s):

Alexander Keylin ◽

Mehdi Ahmadian ◽

Mehdi Taheri ◽

Ali Tajaddini

Keyword(s):

Contact Mechanics ◽

Surface Condition ◽

Field Testing ◽

Test Results ◽

Full Size ◽

Test Conditions ◽

Roller Rig ◽

Analytical Expressions ◽

Roller Radius ◽

Track Irregularities

This study derives explicit analytical expressions for comparing contact patch dimensions and Kalker’s coefficients for a wheel moving on a roller and compares the results with a tangent track arrangement. The expressions suggest that full size roller rig will underpredict Kalker’s traction coefficients (creepage forces per unit creepage) by a factor that depends on the roller radius. Studying rail-wheel contact mechanics and dynamics in the field conditions can prove to be challenging due to the difficulties in adequately controlling the test conditions that can significantly affect the results, such as track irregularities, rail surface condition, etc. Roller rigs can prove to be a useful tool for such studies. One, however, must be careful when interpreting roller rig test results because of the differences in wheel-rail contact mechanics and dynamics between the track and the roller. The findings of this study, which are consistent with other studies’ conclusions, will allow researchers to relate results with field testing.

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Experiences in Field Testing a Variety of Aeration Equipment in Sweden and in the U.S.A. by Offgas Analysis

Water Science & Technology ◽

10.2166/wst.1989.0338 ◽

1989 ◽

Vol 21 (10-11) ◽

pp. 1421-1429

Author(s):

D. T. Redmon ◽

W. C. Boyle ◽

B. G. Hellstrom

Keyword(s):

Oxygen Transfer ◽

State Of The Art ◽

Field Testing ◽

Analysis Procedure ◽

Test Results ◽

Transfer Testing ◽

Parallel Tests

The background and theory of the offgas analysis procedure used in oxygen transfer testing of diffused aeration tanks is reviewed. Correlation of this method with other applicable procedures in parallel tests is reported. State-of-the-art equipment and accessories are described. Advantages of the procedure are identified, as are precautionary considerations regarding its use. Applications considered appropriate for its employment are delineated. Experience and test results in both Sweden and the U.S.A. on a variety of aeration devices are disclosed.

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Answering the Questions of the Psychologist Assessing the Visually Handicapped Child

Journal of Visual Impairment & Blindness ◽

10.1177/0145482x7506900804 ◽

1975 ◽

Vol 69 (8) ◽

pp. 350-353

Author(s):

John L. Morse

Keyword(s):

Classroom Observation ◽

Handicapped Child ◽

Test Results ◽

Visual Condition ◽

Inappropriate Behaviors ◽

Test Conditions ◽

Visually Handicapped ◽

First Time

The most common question asked by the psychologist who is faced for the first time with assessing a visually handicapped child are answered. The 15 questions include such areas as the required information concerning visual condition, background of the client, test conditions, the role of the parents, classroom observation, behaviors observed during testing, evaluation of test results, expectations of parents and teachers, and modification of a child's inappropriate behaviors.

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Simulation of loop test conditions for the modified SM reactor fuel rods and test results in justification of their performance

Izvestiya Wysshikh Uchebnykh Zawedeniy Yadernaya Energetika ◽

10.26583/npe.2013.2.13 ◽

2013 ◽

Vol 2013 (2) ◽

pp. 105-113

Author(s):

Vladimir Aleksandrovich Starkov ◽

Fedoseev V.E. Fedoseev ◽

Shishin V.Yu. Shishin

Keyword(s):

Reactor Fuel ◽

Test Results ◽

Fuel Rods ◽

Test Conditions

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Applied Research on Dynamic Replacement Method in Tailings Residue Subgrade Reinforcement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.639-640.943 ◽

2013 ◽

Vol 639-640 ◽

pp. 943-946

Author(s):

Jiao Long He ◽

Yong Zhou ◽

Zhong Ai Jiang

Keyword(s):

Applied Research ◽

Pore Water Pressure ◽

Water Pressure ◽

Field Testing ◽

Standard Penetration Test ◽

Load Test ◽

Test Results ◽

Replacement Method ◽

Dynamic Replacement ◽

Testing Experiment

Based on the reinforcing mechanism of dynamic replacement method ,this article put forward the construction parameters and measures of dynamic replacement method , combining with the result of actual engineering field testing experiment. The field load test, standard penetration test and pore water pressure test results show that the characteristic value of subgrade bearing capacity is more than 130 kpa when the tailings residue subgrade has been managed with dynamic replacement method, providing references for applied research on dynamic replacement method in tailings residue subgrade reinforcement.

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Measurement Uncertainties Encountered During Gas Turbine Driven Compressor Field Testing

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/98-gt-001 ◽

1998 ◽

Cited By ~ 3

Author(s):

Klaus Brun ◽

Rainer Kurz

Keyword(s):

Measurement Uncertainty ◽

Gas Turbine ◽

Field Test ◽

Equations Of State ◽

Accurate Determination ◽

Field Testing ◽

Significant Implication ◽

Test Results ◽

Measurement Uncertainties

Field testing of gas turbine compressor packages requires the accurate determination of efficiency, capacity, head, power and fuel flow in sometimes less than ideal working environments. Nonetheless, field test results have significant implication for the compressor and gas turbine manufacturers and their customers. Economic considerations demand that the performance and efficiency of an installation are verified to assure a project’s return on investment. Thus, for the compressor and gas turbine manufacturers, as well as for the end-user, an accurate determination of the field performance is of vital interest. This paper describes an analytic method to predict the measurement uncertainty and, thus, the accuracy, of field test results for gas turbine driven compressors. Namely, a method is presented which can be employed to verify the validity of field test performance results. The equations governing the compressor and gas turbine performance uncertainties are rigorously derived and results are numerically compared to actual field test data. Typical field test measurement uncertainties are presented for different sets of instrumentation. Test parameters that correlate to the most significant influence on the performance uncertainties are identified and suggestions are provided on how to minimize their measurement errors. The effect of different equations of state on the calculated performance is also discussed. Results show that compressor efficiency uncertainties can be unacceptably high when some basic rules for accurate testing are violated. However, by following some simple measurement rules and maintaining commonality of the gas equations of state, the overall compressor package performance measurement uncertainty can be limited and meaningful results can be achieved.

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Field testing and probabilistic assessment of ballistic penetration of steel plates for small calibre military ammunition

International Journal of Protective Structures ◽

10.1177/2041419618802593 ◽

2018 ◽

Vol 10 (4) ◽

pp. 421-438 ◽

Cited By ~ 1

Author(s):

Mark G Stewart ◽

Brianna Dorrough ◽

Michael D Netherton

Keyword(s):

Penetration Depth ◽

Field Test ◽

Predictive Models ◽

High Strength ◽

Field Testing ◽

Hardened Steel ◽

Steel Plates ◽

Probabilistic Assessment ◽

Test Results ◽

Terminal Ballistics

The penetration of projectiles into semi-infinite targets helps in the understanding and modelling of terminal ballistics. The article describes field test results of 5.56×45 mm F1 Ball and 7.62×51 mm M80 Ball ammunition. The targets were 25-mm-thick mild and high strength steel plates of Grade 250 MPa and 350 MPa, respectively. The tests recorded penetration depth, muzzle and impact velocities, and bullet mass. Despite its smaller calibre, the 5.56 mm × 45 mm F1 Ball ammunition recorded deeper penetrations than the larger calibre 7.62 mm × 51 mm M80 Ball ammunition. This is due to the 5.56 mm ammunition comprising a hardened steel penetrator and lead core, whereas the 7.62 mm ammunition comprised only a lead core. Multiple shots were fired for each type of munition. The coefficient of variation of steel penetration is approximately 0.10 and 0.03 for 5.56 mm and 7.62 mm rounds, respectively. The article also presents predictive models of steel penetration depth and compares these to the field test results.

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Experimental investigation on the characteristics of the dynamic rail pad force and its stress distribution in the time and frequency domain

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409719838116 ◽

2019 ◽

Vol 234 (2) ◽

pp. 201-213 ◽

Cited By ~ 2

Author(s):

Xu Zhang ◽

Chunfa Zhao ◽

Xiaobo Ren ◽

Yang Feng ◽

Can Shi ◽

...

Keyword(s):

Stress Distribution ◽

Frequency Domain ◽

Maximum Stress ◽

Field Tests ◽

Service Condition ◽

Field Testing ◽

Dominant Frequency ◽

Test Results ◽

Parabolic Shape ◽

Dominant Frequencies

The rail pad force and its stress distribution have critical influences on the performance and fatigue life of the rail, fasteners, and sleepers. The characteristics of the rail pad force and its stress distribution in the time and frequency domain obtained from field tests carried out using matrix-based tactile surface sensor are presented in this paper. The field testing involved rail pads under various axle-loads of running trains at different speeds. The influences that the train axle-load, the operational speed, and the rail pad stiffness have on the rail pad force and its stress distribution are analyzed. The test results indicate that the rail pad stiffness has a remarkable influence on the amplitude of the rail pad force but has little influence on its dominant frequencies. The first dominant frequency of the rail pad force is quite close to the passing frequency of the vehicle length. The stress distribution on the rail pad has a parabolic shape along the longitudinal and the lateral directions with the large stress appearing near the center of the rail pad, and is remarkably affected by the service condition of the rail pad. The maximum stress is about 2.5 to 3 times of the average stress, which is significantly greater than the nominal stress resulting from the assumption of uniform stress distribution.

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Field Testing of the Flowback Technology for Multistage-Fractured Horizontal Wells: Test Results and Primary Interpretation of the Results

10.2118/202056-ms ◽

2020 ◽

Author(s):

Albert Vainshtein ◽

Georgii Fisher ◽

Sergei Boronin ◽

Andrei Osiptsov ◽

Ildar Faysullin ◽

...

Keyword(s):

Horizontal Wells ◽

Field Testing ◽

Test Results ◽

Fractured Horizontal Wells

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Near-Field Immunity Test Method for Fast Radiated Immunity Test Debugging of Automotive Electronics

Electronics ◽

10.3390/electronics8070797 ◽

2019 ◽

Vol 8 (7) ◽

pp. 797 ◽

Cited By ~ 1

Author(s):

Jawad Yousaf ◽

Doojin Lee ◽

JunHee Han ◽

Hosang Lee ◽

Muhammad Faisal ◽

...

Keyword(s):

Automotive Industry ◽

Near Field ◽

Cost Effective ◽

Field Testing ◽

Input Power ◽

Test Method ◽

Automotive Electronics ◽

Test Results ◽

Electric Power Steering ◽

Power Steering

This study presents a near-field immunity test (NFIT) method for the fast debugging of radiated susceptibility of industrial devices. The proposed approach is based on the development of an NFIT setup which comprises of developed near-field electric and magnetic field probes and device under test (DUT). The developed small-size and handy near-field testing probes inject the high electric (up to 1000 V/m) and magnetic (up to 2.4 A/m) fields on the DUT in the radar pulse ranges (1.2 to 1.4 GHz and 2.7 to 3.1 GHz) with the lower fed input power (up to 15 W) from the power amplifier in the developed NFIT setup. The proof of concept is validated with the successful near-field immunity debugging of an electric power steering (EPS) device used in the automotive industry with the developed NFIT setup. The radiated susceptibility debugging test results of developed NFIT method and conventional method of ISO 11452-2 test setup turned out to be close to each other for the tested DUT in immunity performance. The proposed procedure has advantages of industry usefulness with fast, handy, and cost-effective radiated immunity debugging of the DUT without the requirement of large antenna, high-power amplifiers, optical DUT connecting harness, and an anechoic chamber as needed in ISO 11452-2 standard setup for the debugging analysis.

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