scholarly journals Influence of undefined modes of movement on instantaneous redistribution of normal reactions of quarry dump truck tires

2021 ◽  
Vol 315 ◽  
pp. 03014
Author(s):  
Mikhail Dadonov ◽  
Alexander Kulpin ◽  
Evdokia Kulpina ◽  
Valery Borovtsov ◽  
Gulzira Mukasheva
Keyword(s):  
Normal Load ◽  
Ambient Air ◽  
Climatic Conditions ◽  
Operating Conditions ◽  
Dump Truck ◽  
The Road ◽  
Truck Tires ◽  
Non Linear ◽  
Main Thing ◽  
The Impact

Reducing the costs of rock transportation in mining is one of the most important tasks. One of the reserves for solving this issue is a more complete use of the service life of quarry dump trucks tires, since their operation takes place in heavy mining and climatic conditions and this significantly reduces the life of tires. The life of tires depends on many factors: speed of movement, compliance with the recommended air pressure in the tire, ambient air temperature, but the main thing is the change in the normal load on the wheel, which depends on the redistribution of the quarry dump truck weight in case of non-linear movement and on the longitudinal profile of the quarry road. In real conditions, the quarry dump truck moves unevenly due to the complexity of the road - either braking or acceleration occur. This article allows you to evaluate the impact of non-linear modes of quarry dump truck movement on the instant redistribution of normal tire reactions and take into account peak loads on wheels during acceleration and braking in the regular cycle. This will allow you to control the load on the tires directly by cargo amount in the quarry dump truck and thereby increase the life of the tires and their reliability, as well as reduce the cost of transporting the rock mass in real operating conditions.

scholarly journals Effect of aerodynamic loads on redistribution of normal reactions of quarry dump trucks tires

2020 ◽  
Vol 174 ◽  
pp. 03018
Author(s):  
Mikhail Dadonov ◽  
Alexander Kulpin ◽  
Valery Borovtsov ◽  
Anar Zhunusbekova
Keyword(s):  
Normal Load ◽  
Operating Conditions ◽  
Dump Truck ◽  
Early Failure ◽  
Aerodynamic Loads ◽  
Truck Tires ◽  
Dump Trucks ◽  
And Control ◽  
Mine Dump

Tires of quarry dump trucks occupy one of the leading places in the item of costs for motor transport, as they are expensive product and at the same time more than half of them do not generate their resource. The causes of premature tires failure are exceeding normal load on them. In turn, the aerodynamic forces effect on the quarry dump truck as one of the influencing factors, is the dynamic redistribution of normal loads on tires and, as a result, affects temperature modes. The determination of the load on the tire under different operating conditions will increase the service life of the tires and avoid early failure. The proposed calculation method of aerodynamic loads and their influence on redistribution of normal mine dump truck tires reactions in dynamics allows to make correction to load modes and control the tires resource, which will lead to more complete use of tires resource.

Impact of climatic conditions on the parameters of failure flow of military vehicles

2021 ◽  
pp. 095440702110202
Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys
Keyword(s):  
Climatic Factors ◽  
Armed Forces ◽  
Climatic Conditions ◽  
Operating Conditions ◽  
Technical Equipment ◽  
Factors Affecting ◽  
Military Vehicles ◽  
Equipment Reliability ◽  
Number Of Factors ◽  
The Impact

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.

scholarly journals Comparative Study of the Heat and Mass Transfer Characteristics between Counter-Flow and Cross-Flow Heat Source Towers

Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2674 ◽  
Author(s):  
Yifei Lv ◽  
Jun Lu ◽  
Yongcai Li ◽  
Ling Xie ◽  
Lulu Yang ◽  
...  
Keyword(s):  
Heat Source ◽  
Cross Flow ◽  
Ambient Air ◽  
Packing Material ◽  
Operating Conditions ◽  
Solution Temperature ◽  
Low Grade ◽  
Counter Flow ◽  
Heat Pump Unit ◽  
The Impact

The heat source tower (HST), as a cleaner energy production, which can absorb the low-grade energy from ambient air to drive the heat pump unit without emissions has attracted more and more interest. In addition, HST has excellent economic applicability by using cooling tower equipment, which was idle in winter. However, there are few studies on comparative analysis of thermal behavior between counter-flow and cross-flow HST. A mathematical model suitable for both HST types was developed to identify the performance discrepancies between them. Then a parametric study was carried out in order to investigate the impact of solution and air as well as packing material properties on energy transfer of HSTs. Finally, the characteristics of solution dilution and dehumidification were investigated. As the inlet solution temperature increases, increases first, then decreases gradually, but a transition point occurs in the solution at −5 °C. Moreover, the transition section of moisture transfer direction for counter-flow HST was located in the 0.78 m and 0.26–1.56 m of packing material height, under the condition that the air relative humidity was 50%. In summary, this work intuitively indicates the thermal performance difference between counter-flow and cross-flow HST, also could assist the selection of proper operating conditions in HSTs.

scholarly journals Influence of climatic conditions on the occurrence of wheel track deformation on asphalt paved roads

2021 ◽  
Vol 264 ◽  
pp. 02028
Author(s):  
Iroda Saidakberova ◽  
Sirojiddin Yadgarov ◽  
Bobomurod Qurbonov ◽  
Zulfiya Pulatova
Keyword(s):  
Climatic Factors ◽  
Climatic Conditions ◽  
Dynamic Force ◽  
The Road ◽  
Transverse Dynamic ◽  
Road Pavement ◽  
The Impact ◽  
Track Deformation ◽  
Wheel Track ◽  
Repeated Loads

When the car moves, a vertical, longitudinal and transverse dynamic force is generated, where there is a link between the road cover and the wheel. Repeated loads from vehicles and the impact of climatic factors lead to deformation in the pavement and pavement of the road. In deformation and deformation, the geometric dimensions and durability of the road pavement are lost. Disturbances-loss of dimensions and loss of durability of parts of the construction is understood. In practice, all types of deformation and distortion are often regarded as a drawback of road conditions [1].

Modeling and Analysis of Tier 4 Locomotives Operating in a High-Altitude Tunnel

2017 ◽  
Author(s):  
Kevin S. McElhaney ◽  
Robert Mischler
Keyword(s):  
High Altitude ◽  
Diesel Engines ◽  
Ambient Air ◽  
Operating Conditions ◽  
Tier 2 ◽  
Electric Locomotive ◽  
Design Changes ◽  
Engine Design ◽  
The Impact ◽  
Cooling And Lubrication

Tunnels represent one of the most severe operating conditions for diesel engines in diesel-electric locomotive applications, specifically for non-ventilated tunnels located at high elevation. High ambient air temperatures are observed in these tunnels due to heat rejected from the locomotive engines through the exhaust and engine cooling and lubrication systems. Engine protection algorithms cause the maximum allowable engine horsepower to be reduced due to these conditions leading to a reduction in train speed and occasionally train stall. A first law based model was developed to simulate the performance of a train pulled by GE diesel-electric locomotives equipped with medium speed diesel engines in a high altitude and non-ventilated tunnel. The model was compared against and calibrated to actual tunnel operation data of EPA Tier 2 compliant locomotives. The model was then used to study the impact of engine design changes required for EPA Tier 4 compliant locomotives, specifically the introduction of exhaust gas recirculation (EGR), on engine, locomotive, and train performance in the tunnel. Simulations were completed to evaluate engine control strategies targeting same or better train performance than the EPA Tier 2 compliant locomotive baseline case. Simulation results show that the introduction of EGR reduces train performance in the tunnel by increasing the required reduction in engine horsepower, but is slightly offset by improved performance from other engine design changes. The targeted engine and train performance could be obtained by disabling EGR during tunnel operation.

scholarly journals Stress concentration in the vicinity of road сoating cracks

2021 ◽  
pp. 41-53
Author(s):  
Viktor Gaidaichuk ◽  
Liudmyla Shevchuk ◽  
Olena Bilobrytska ◽  
Serhii Baran
Keyword(s):  
Stress Concentration ◽  
Mechanical Behavior ◽  
Asphalt Concrete ◽  
Plastic Material ◽  
Multilayer Coating ◽  
Three Dimensional ◽  
Element Model ◽  
Operating Conditions ◽  
The Road ◽  
The Impact

The article presents the results of a computer analysis of the stress-strain state of a multilayer asphalt pavement under the influence of traffic loads. Based on the finite-element model of coating deformation, a study was made of the mechanical behavior of the system considered for various structural schemes for the existence of vertical cracks in various layers of the structure under the action of vertical transport loads. The effects of stress concentration in the system due to high-gradient deformation fields and structural imperfections of the multilayer coating were found. Multi-layer asphalt roads are one of the most common construction projects. Based on a review of the tasks of science about their strength and durability, these structures can be attributed to significantly complex types of building systems. This is primarily due to the multi-parameter nature of the factors that determine their design, material properties, types of loads and the impact on them, as well as their operating conditions. Therefore, designers of road structures and specialists who are involved in the theoretical modeling of the mechanical behavior of layered massifs during operation have to take into account many additional factors that complicate their work. These include the most important design and operational features of these systems, which significantly affect the nature of the distribution of stress and strain fields, as well as their intensity. First of all, they include special structural schemes of the road and pavement. It is a multilayer three-dimensional package having disproportionately different sizes along each direction. Hidden (as well as obvious) vertical cracks and horizontal delamination of the structure, sometimes permissible under operating conditions, can be added to the design model of a structure. Such violations of the continuity of the system also lead to discontinuity of the displacement functions, which further worsens the system’s performance and complicates the task of its modeling. The materials of the coating layers, which include asphalt concrete, cement, crushed stone, sand, soil, and others, also bring particular specificity to the work of the road structure. All of them differently resist tensile, compression and shear, and asphalt concrete is also elastic-viscous - plastic material, whose properties are largely dependent on temperature.

A mitigation study for air pollution management across Germany for NOX (NO + NO2) with the LOTOS-EUROS CTM – Part I: Comparing the labeling and brute force technique for source attribution.

2021 ◽  
Author(s):  
Markus Thürkow ◽  
Joscha Pültz ◽  
Martijn Schaap
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Ambient Air ◽  
Brute Force ◽  
Ambient Air Quality ◽  
Source Attribution ◽  
Application Range ◽  
Impact Studies ◽  
Non Linear ◽  
The Impact

<p>Air quality is a key aspect of present environmental discussions with nitrogen oxides (NO<sub>X</sub> = NO + NO<sub>2</sub>) has become a decisive element and impact factor for air quality planning. Millions of people are exposed by NO<sub>2,</sub> especially in urban areas near traffic sites, leading to increased mortality rates. As the annual limit value of 40 μg/m<sup>3</sup>, introduced by the European Ambient Air Quality Directive (EC, 2008), is currently exceeded by about 39 % (UBA, 2019), in Germany an estimated number of 13.100 premature deaths are caused by NO<sub>2</sub> (EEA, 2018). The origin and formation processes of NO<sub>X</sub> are well documented in literature for long: NO mainly originates from incomplete combustion (Granier et al., 2011; Vestreng et al., 2009), with NO<sub>2</sub> formed as a photochemical reaction product (Finlayson-Pitts and Pitts, 2000; Leighton, 1961). Therefore, to further improve the ambient air quality using cost-effective mitigation strategies, this requires for quantifying the contribution of the ambient air pollution by source sectors and regions of their origin (Belis et al., 2020).</p><p>Applying chemical transport models (CTMs) for source attribution (SA), one can distinguish between contributions and impacts. Methods to estimate contributions are known as labeling (Kranenburg et al., 2013) or tagging (Wang et al., 2009; Wagstrom et al., 2008) approaches and are based on conservation of mass. In contrast, sensitivity simulations, such as the top-down brute force (BF) technique, can be used to quantify the impact to different emission reductions (Clappier et al., 2017; Thunis et al., 2019). As the BF approach in theory is only designed for impact studies, the calculation of contributions can result in incorrect estimates which is dependent on the linearity of the considered component (Clappier et al., 2017; Thunis et al., 2019). Therefore, impact studies can only be employed under certain restrictions and their application range needs to be predefined first (Thunis et al., 2020).</p><p>Previous studies primarily focused on PM when comparing different approaches for SA. Therefore, we conducted a SA study by performing air pollution simulations using the LOTOS-EUROS CTM across Germany of January 1<sup>st</sup> to December 31<sup>st</sup>, 2018 for NO<sub>X</sub>. We enhanced the understanding of limitations to non-linear interaction terms and defined the potential application range for SA purposes using impact studies of NO<sub>X</sub>, by comparing the labeling approach implemented in the LOTOS-EUROS CTM to the BF technique.</p><p>First results indicate that impact studies cannot be used to estimate contributions of NO due to their non-linear relations and inconsistent mass conservation. Even though differences for NO<sub>2 </sub>are smaller, it is not recommended to apply the BF technique here either. However, considering that non-emission sources cannot be separated from each other in impact studies, it is further advised not to apply this method for NO<sub>X</sub>.</p>

scholarly journals A GPU-Accelerated Compressible RANS Solver for Fluid-Structure Interaction Simulations in Turbomachinery

2016 ◽  
Author(s):  
L. Mangani ◽  
E. Casartelli ◽  
G. Romanelli ◽  
Magnus Fischer ◽  
A. Gadda ◽  
...  
Keyword(s):  
Computational Efficiency ◽  
Power Efficiency ◽  
Linear Time ◽  
Fluid Structure Interaction ◽  
Operating Conditions ◽  
Structural Deformation ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Non Linear ◽  
The Impact

Computational Fluid Dynamics (CFD) is a fundamental tool for the aerodynamic development in industrial applications. In the usual approach structural deformation due to aerodynamic and thermal loads is often neglected. However, in some cases, where power efficiency is the ultimate goal, an accurate prediction of the structure-flow interaction is essential. This is particularly true for trim and flutter analysis of aircrafts, helicopter and turbomachinery blades. Particularly, turbomachinery trim and flutter predictions still represent a challenge due to phenomena like rotor-stator interaction, separations and shock waves. The usual time-linearised, frequency-domain strategies can be inadequate when this kind of strong non-linear phenomena occur in the flow, making necessary full non-linear time-domain simulations or the harmonic balance technique. Beside flutter, another important aspect, not yet adequately investigated, is the trim analysis, which is fundamental for an accurate steady simulation that aims to consider static blade elasticity for the performance evaluation of turbomachines. Moreover, alongside the obvious contribution given by centrifugal loads to the blade deformation, a not less important source of blade displacement is the thermal effect due to the heat exchanged between the solid and the fluid domains. In particular, for some geometries and operating conditions, thermal effects can be more important than centrifugal effects for the blade deformations. Considering multiple sources of blade deformation (elastic, centrifugal and thermal) in a what is often called “multiphysics” approach is nowadays more and more important, if the goal of the analysis is geometry optimization. To achieve this, next to result’s accuracy also computational efficiency is required, when hundreds of aeroelastic simulations have to be performed in a typical optimization loop. Modern GPUs can be exploited to pursue this goal thanks to their high peak computational power available at relatively low costs and low power consumption with respect to the usual CPUs. In this paper a pioneer work describing the impact of static deformation due to blade elasticity, thermal and centrifugal effects on the performances and power efficiency will be provided. Alongside with accurate results, computational efficiency is taken into account. The purpose of this article is to show the architecture of a GPU-accelerated Fluid-Structure Interaction (FSI) solver for compressible viscous flows. The proposed approach is validated with a typical industrial case, i.e. a turbocharger transonic centrifugal-compressor provided by ABB. The effects of trimmed solutions on the most important integral quantities (i.e. mass flow, characteristic curves, mass-averaged outflow profiles) are investigated and a comparison with pure aerodynamic results is provided. Due to the high blade stiffness and thus the very small displacements obtained with the trim solutions, for the particular case presented in the paper the aeroelastic solutions basically provide nearly the same results as the pure aerodynamic solutions.

scholarly journals Non-Linear Regression Modelling to Estimate the Global Warming Potential of a Newspaper

Entropy ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 590
Author(s):  
Alexis Lozano ◽  
Pedro Cabrera ◽  
Ana M. Blanco-Marigorta
Keyword(s):  
Linear Regression ◽  
Environmental Sustainability ◽  
Regression Models ◽  
Raw Materials ◽  
Operating Conditions ◽  
Raw Material ◽  
Linear Regression Models ◽  
Daily Production ◽  
Non Linear ◽  
The Impact

Technological innovations are not enough by themselves to achieve social and environmental sustainability in companies. Sustainable development aims to determine the environmental impact of a product and the hidden price of products and services through the concept of radical transparency. This means that companies should show and disclose the impact on the environment of any good or service. This way, the consumer can choose in a transparent manner, not only for the price. The use of the eco-label as a European eco-label, which bases its criteria on life cycle assessment, could provide an indicator of corporate social responsibility for a given product. However, it does not give a full guarantee that the product was obtained in a sustainable manner. The aim of this work is to provide a way of calculating the value of the environmental impacts of an industrial product, under different operating conditions, so that each company can provide detailed information on the impacts of its products, information that can form part of its "green product sheet". As a case study, the daily production of a newspaper, printed by coldset, has been chosen. Each process involved in production was configured with raw material and energy consumption information from production plants, manufacturer data and existing databases. Four non-linear regression models have been trained to estimate the impact of a newspaper’s circulation from five input variables (pages, grammage, height, paper type, and print run) with 5508 data samples each. These non-linear regression models were trained using the Levenberg–Marquardt nonlinear least squares algorithm. The mean absolute percentage errors (MAPE) obtained by all the non-linear regression models tested were less than 5%. Through the proposed correlations, it is possible to obtain a score that reports on the impact of the product for different operating conditions and several types of raw materials. Ecolabelling can be further developed by incorporating a scoring system for the impact caused by the product or process, using a standardised impact methodology.

scholarly journals Distribution of Static Normal Reactions to Wheels of Open-Pit Dump Trucks Depending on the Longitudinal and Cross Sections of the Open-Pit Road

2019 ◽  
Vol 105 ◽  
pp. 03009
Author(s):  
Michail Dadonov ◽  
Alexander Kulpin ◽  
Oleg Ostanin ◽  
Erkin Suleimenov
Keyword(s):  
Rock Mass ◽  
Cross Sections ◽  
Normal Load ◽  
Operating Conditions ◽  
Open Pit ◽  
Dump Truck ◽  
Mass Transportation ◽  
Premature Failure ◽  
Dump Trucks ◽  
The Cost

Vehicle costs for rock mass transportation are more than 50% of total costs, among which 25 — 30% are tire costs. The average tire life in mining enterprises is lower than that the value recommended by production plants. The tire life of open-pit dump trucks is more dependent on the normal load on the wheel. The main factor in the change of the normal load is location of the wheel on the dump truck and the open-pit road’s section. Determination of the maximum loaded tire in different operating conditions will allow increasing the tire life and preventing its premature failure. The TKPH index (tire performance) recommended by tire manufacturers does not take into account the diversity of mining conditions and variations of sections of open-pit roads on different routes. The average load per trip is defined as movement of a loaded open-pit truck and an empty open-pit truck on a straight reach of a road. The proposed method for recording of redistribution of the load on the wheel allows making adjustments to recording of TKPH indexes and thereby effectively managing the tire life, which in turn will make it possible to more fully use the tire life, increase its reliability and reduce the cost of rock mass transportation.

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