Design and performance of a low-speed weigh-in-motion system

Under the condition of dynamic weighing, the support types of the column load cells can be divided into elastic support and oscillation support. The weighing system with oscillation support shows significant vibration characteristics, which affects the weighing accuracy and the fatigue life of the load sensor. In this paper, the dynamic characteristics of the oscillation supporting column load cell in low speed axle-group weigh-in-motion system are analysed. It is found that the restoring force of the oscillation support is approximately proportional to the oscillation angle and the applied vertical load. The dynamic equation of the oscillation support vibration of the column load cells established by means of d’Alembert principle. The numerical calculations of the dynamic response of the weighing system with oscillation support are carried out in the free state and dynamic weighing state respectively. The factors affecting the amplitude and recovery time of the support vibration are obtained. This study provides a reference for the analysis of the dynamic weighing accuracy.

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Comparative Accuracy Analysis of Truck Weight Measurement Techniques

Applied Sciences ◽

10.3390/app11020745 ◽

2021 ◽

Vol 11 (2) ◽

pp. 745

Author(s):

Sylwia Stawska ◽

Jacek Chmielewski ◽

Magdalena Bacharz ◽

Kamil Bacharz ◽

Andrzej Nowak

Keyword(s):

Measurement Techniques ◽

Highway Traffic ◽

Highway Infrastructure ◽

Measurement Systems ◽

Motion System ◽

Weigh In Motion ◽

Comparative Accuracy ◽

Bridge Weigh In Motion ◽

Rational Management ◽

Truck Weight

Roads and bridges are designed to meet the transportation demands for traffic volume and loading. Knowledge of the actual traffic is needed for a rational management of highway infrastructure. There are various procedures and equipment for measuring truck weight, including static and in weigh-in-motion techniques. This paper aims to compare four systems: portable scale, stationary truck weigh station, pavement weigh-in-motion system (WIM), and bridge weigh-in-motion system (B-WIM). The first two are reliable, but they have limitations as they can measure only a small fraction of the highway traffic. Weigh-in-motion (WIM) measurements allow for a continuous recording of vehicles. The presented study database was obtained at a location that allowed for recording the same traffic using all four measurement systems. For individual vehicles captured on a portable scale, the results were directly compared with the three other systems’ measurements. The conclusion is that all four systems produce the results that are within the required and expected accuracy. The recommendation for an application depends on other constraints such as continuous measurement, installation and operation costs, and traffic obstruction.

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Design and Performance of an Ultra-Compact Low-Speed Low-Turbulence Level Wind Tunnel for Aerodynamic and Animal Flight Experiments

AIAA AVIATION 2020 FORUM ◽

10.2514/6.2020-3107 ◽

2020 ◽

Author(s):

Kenny S. Breuer ◽

Mark Drela ◽

Xiaozhou Fan ◽

Matteo di Luca

Keyword(s):

Wind Tunnel ◽

Turbulence Level ◽

Low Speed ◽

And Performance ◽

Animal Flight

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Modeling and performance analysis of diesel engine considering the heating effect of blow-by on cylinder intake gas

International Journal of Engine Research ◽

10.1177/14680874211069217 ◽

2021 ◽

pp. 146808742110692

Author(s):

Zhenyu Shen ◽

Yanjun Li ◽

Nan Xu ◽

Baozhi Sun ◽

Yunpeng Fu ◽

...

Keyword(s):

Diesel Engine ◽

Engine Performance ◽

Marine Diesel Engine ◽

Heating Effect ◽

Shipping Industry ◽

Low Speed ◽

Proposed Model ◽

International Regulations ◽

Marine Diesel ◽

And Performance

Recently, the stringent international regulations on ship energy efficiency and NOx emissions from ocean-going ships make energy conservation and emission reduction be the theme of the shipping industry. Due to its fuel economy and reliability, most large commercial vessels are propelled by a low-speed two-stroke marine diesel engine, which consumes most of the fuel in the ship. In the present work, a zero-dimensional model is developed, which considers the blow-by, exhaust gas bypass, gas exchange, turbocharger, and heat transfer. Meanwhile, the model is improved by considering the heating effect of the blow-by gas on the intake gas. The proposed model is applied to a MAN B&W low-speed two-stroke marine diesel engine and validated with the engine shop test data. The simulation results are in good agreement with the experimental results. The accuracy of the model is greatly improved after considering the heating effect of blow-by gas. The model accuracy of most parameters has been improved from within 5% to within 2%, by considering the heating effect of blow-by gas. Finally, the influence of blow-by area change on engine performance is analyzed with considering and without considering the heating effect of blow-by.

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