INFLUENCE OF TIRE DEBRIS ON TIRE PERFORMANCE

ABSTRACT A large number of wear debris particles can be found on the tread surface at any time during normal tire operation. In highly accelerated lab tests, it has been shown that wet friction is decreased by the buildup of debris, and the level of friction can be increased when debris is effectively removed from the interface. In wet traction tests on the road, it has been shown that when tires are cleaned from debris, a higher braking force coefficient in straight-ahead braking on wet asphalt is achieved, compared with the same tires that were not cleaned from debris prior to tests. This was observed for both carbon black– and silica-filled tread compounds. It has also been shown that laboratory wear rate can be increased by effective removal of debris. We propose that the presence of tread-wear debris on the tread surface in dry operating conditions would be beneficial for abrasion resistance and, on the other hand, debris removal from the tread surface in wet operating conditions would be beneficial for wet skid resistance.

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DETERMINATION OF MOST SIGNIFICANT FACTORS FOR ANALYSIS OF HIGHWAY OPERATING CONDITIONS

Science & Technique ◽

10.21122/2227-1031-2017-16-6-493-497 ◽

2017 ◽

Vol 16 (6) ◽

pp. 493-497

Author(s):

M. G. Solodkaya

Keyword(s):

Real Life ◽

Operating Conditions ◽

Dynamic Loads ◽

Vehicle Speed ◽

Vehicle Dynamic ◽

The Road ◽

Road Pavement ◽

On The Road ◽

Significant Factors ◽

Road System

Traffic circulation on highways is a random process. Therefore automotive damage rate and, respectively, roads on which they are moving is subjected to regularities of random processes. Dynamic processes of vehicle-road interaction are determined to various extents by a host of factors that include road pavement evenness and characteristics of moving vehicles. For this reason the following task has been set: to reveal the most significant factors and mathematically correlate values of vehicle dynamic loads with a quality of road pavement and vehicle speed. Such task statement has not been solved adequately and this situation determines importance and novelty of the investigations in the given direction. While solving the mentioned task the investigations which have been carried out under real-life conditions and with the help of real-life objects are considered as the most reliable ones. However, preparation and execution of such experiments as needed significantly complicates their implementation. In this regard it looks rather expediential to combine a factorial experiment with the tests of a checked model while using ECM with stage-by-stage parameter fixation of working processes passing in “vehicle-road” system, comprehensive assessment pertaining to influence of the selected factors and selection of their optimum combination. Mathematical dependence has been obtained to evaluate influence of several external factors on optimization of vehicle dynamic load on the road. This component makes it possible to attain a simplified and adequate description of element interaction in “vehicle – road” system. While investigating influence of pavement irregularities on maximum dynamic loads on the road influence rate of the selected factors is determined in the following sequence: vehicle weight, pavement evenness and speed of transport facility.

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Investigation and Comparison of Tires Perfomance on Ice

Proccedings of 10th International Conference "Environmental Engineering" ◽

10.3846/enviro.2017.146 ◽

2017 ◽

Cited By ~ 1

Author(s):

Andrius Ružinskas ◽

Henrikas Sivilevicius

Keyword(s):

Lateral Force ◽

Operating Conditions ◽

Slip Angle ◽

Transmission Measurement ◽

Force Transmission ◽

Force Coefficient ◽

Slip Ratio ◽

The Road ◽

Tire Force ◽

Main Component

The risk of accident increases significantly when tire rolls on ice comparing to the dry surface. The vehicle tire becomes the main component of force transmission to the road and necessity of investigating the tire behavior becomes of high importance. This paper presents results of tire force transmission measurement with two different winter tires at the same operating conditions. Longitudinal and lateral force coefficient characteristics as the functions of slip ratio and slip angle are presented and discussed. The results showed a different lateral and longitudinal performance because of different tread pattern and rubber compound.

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PEMS-based investigations into exhaust emissions from non-road and rail vehicles

Combustion Engines ◽

10.19206/ce-2016-339 ◽

2016 ◽

Vol 166 (3) ◽

pp. 46-53

Author(s):

Jerzy Merkisz ◽

Piotr Lijewski ◽

Jacek Pielecha

Keyword(s):

Operating Conditions ◽

Rolling Stock ◽

Negative Effects ◽

Engine Emissions ◽

The Road ◽

Rail Vehicles ◽

Wide Range ◽

Mobile Machinery ◽

On The Road ◽

Method Of Evaluation

At the beginning of the twenty-first century, one of the major challenges of humanity was to reduce the negative effects of civilization development. Besides the engines used in road vehicles there is a large group of engines for non-road applications. This group includes motor propelled vehicles not used on the road NRMM (Non-Road Mobile Machinery). Engines of these vehicles, among all of the non-road applications, are characterized by very specific working conditions that do not allow for them to be qualified for propulsion engines. The main problem with these vehicles is the particulate matter and nitrogen oxides emission. Rail vehicles operating conditions these requirements take by the similar way, as having a wide range of rolling stock markedly alters the environmental impact of these vehicles. Thus it becomes necessary to consider the issue of the method of evaluation of engine emissions in rail vehicles in terms of their actual operating conditions. Thus, efforts to assess the actual level of emissivity for rail vehicles and attempts to improve it are necessary and justified.

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Research on the road linear optimization design of bridge and tunnel connecting segment in the canyon

Archives of Transport ◽

10.5604/01.3001.0014.0209 ◽

2019 ◽

Vol 52 (4) ◽

pp. 67-79

Author(s):

Lu Wang ◽

Yuwen Liu ◽

Xiaoxin Chen

Keyword(s):

Traffic Management ◽

Optimization Design ◽

Linear Optimization ◽

Lateral Acceleration ◽

Speed Limit ◽

Force Coefficient ◽

Minimum Radius ◽

The Road ◽

On The Road ◽

Circular Curve

It is easy to skid and roll by centrifugal force and wind, which affects the safety of the vehicle. At the same time, the special location of bridge and tunnel connecting segment in the canyon will accelerate the wind, and make the transverse wind play a more important role in driving vehicles. Based on the acceleration effect of canyons on wind, the vehicle model is simulated by Carsim software, and the road and wind models are established. It is studied that the vehicle has different radius of circular curve under different wind levels, corresponding to different superelevation. The lateral acceleration, lateral deflection and transverse force coefficient are selected as the running state of the vehicle at different speeds to research the linear optimization design of bridge and tunnel connecting segment in the canyon. The result shows that when the wind force exceeds the fifth grade, it is possible for the vehicle to overturn under the limit minimum radius required by the standard value. In order to ensure the stability and safety of the vehicle, this paper considers the geographical position of bridge and tunnel connecting segment in the canyon and the relationship between the radius of the superelevation and circular curve. What’s more, it puts forward the optimal limit minimum radius of the circular curve with different wind grades of 5-9 grades. At the same time, when the road alignment cannot be optimized under the condition, this paper puts forward the speed limit that the vehicle safety can be guaranteed under different wind speed conditions. The speed limit can provide reference for traffic management and safety guarantee of mountain expressway.

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Parameters Influencing on Electric Vehicle Range

Energies ◽

10.3390/en14164821 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4821

Author(s):

Emilia M. Szumska ◽

Rafał S. Jurecki

Keyword(s):

Energy Consumption ◽

Electric Vehicle ◽

Limited Range ◽

Operating Conditions ◽

Consumption Pattern ◽

Initial State ◽

The Road ◽

Depth Of Discharge ◽

Vehicle Operation ◽

On The Road

There is a range of anxiety-related phenomena among users and potential buyers of electric vehicles. Chief among them is the fear of the vehicle stopping and its users getting “stuck” before reaching their designated destination. The limited range of an electric vehicle makes EV users worry that the battery will drain while driving and the vehicle will stall on the road. It is therefore important to know the factors that could further reduce the range during daily vehicle operation. The purpose of this study was to determine the effect of selected parameters on a battery’s depth of discharge (DOD). In a simulation study of an electric vehicle, the effects of the driving cycle, ambient temperature, load, and initial state of charge of the accumulator on the energy consumption pattern and a battery’s depth of discharge (DOD) were analyzed. The simulation results confirmed that the route taken has the highest impact on energy consumption. The presented results show how significantly the operating conditions of an electric vehicle affect the energy life. This translates into an electric vehicle’s range.

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Application of a Digital Strain Analyzer AutoGrid at Thin Sheet Metals Mechanical Characteristics Preparation and Assessment of their Drawability

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.246.75 ◽

2016 ◽

Vol 246 ◽

pp. 75-78

Author(s):

Monika Hyrcza-Michalska

Keyword(s):

Numerical Simulation ◽

Sheet Metal ◽

Thin Sheet ◽

Operating Conditions ◽

Inconel 625 ◽

Forming Limit ◽

The Road ◽

Inconel Alloys ◽

Thin Sheet Metal ◽

On The Road

The paper presents the results of mechanical properties testing of thin sheet metal of INCONEL 625 and 718 alloys. These studies are a continuation of experience in the preparation of the technological characteristics of metal strips plasticity necessary for carrying out numerical simulations [1]. In order to process sheets now become necessary to design the process using software such as thermo-mechanical simulation e.g. Eta/DYNAFORM. On the road of numerical simulation are sought optimal conditions for processing sheets. It brings reducing the cost of industrial tests. However, becomes strictly necessary characteristics of mechanical and technological properties describing the characteristics of the charges for forming. Here the problem is solved if we forming limit curves (FLCs) designated and technological tests conducted. Using the FLCs is comprehensively defined stamping sheet metal press formability and technological tests allow the mapping of the actual operating conditions selected stamping operations. In the presented study used modern digital analyzer AutoGrid of local deformations and the method of image analysis of deformed mesh subdivision. The use of mesh analyzer and vision systems method significantly speeds up the possibility of producing FLCs. Also measurement accuracy is very high. Selected Inconel alloys are evaluated quantitatively and qualitatively by preparing their properties characterization. The acquired data entered into the database material properties of sheet metal and used in the numerical simulation of stamping process of Inconel 625 cone drawpiece. The legitimacy of the use of modern strain analyzer AutoGrid has been confirmed.

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ANALYSIS OF EXTERNAL COSTS OF CO2 EMISSIONS FOR CNG BUSES IN INTERCITY BUS SERVICE

Transport ◽

10.3846/transport.2019.11473 ◽

2019 ◽

Vol 34 (5) ◽

pp. 529-538 ◽

Cited By ~ 1

Author(s):

Ivan Ivković ◽

Snežana Kaplanović ◽

Dragan Sekulić

Keyword(s):

Co2 Emissions ◽

Road Network ◽

Alternative Fuels ◽

Operating Conditions ◽

Transport Sector ◽

External Costs ◽

The Road ◽

Diesel Buses ◽

On The Road ◽

Bus Service

Within the transport sector, road transport is the largest source of Carbon Dioxide (CO2) emissions. Greater use of vehicles that run on clean alternative fuels can contribute to reduce CO2 emissions. This paper gives special attention to the Compressed Natural Gas (CNG) buses and their comparison with conventional diesel buses, which in countries such as Serbia have a dominant share. Justification of using CNG buses in order to mitigate climate changes is measured by realised annual and average external costs of CO2 emissions. These external costs provide a basis for future use of economic instruments by which negative impacts of transport on the environment can be limited. Research of CO2 emissions and external costs of CO2 emissions in intercity bus service was conducted for three technical-technological concepts of CNG buses in comparison to the two types of conventional diesel buses. Analysis was carried out according to four various scenarios that define different operating conditions on the road network of the Serbia. Obtained results show that CNG buses reduce annual external costs of CO2 emissions by 2…24% compared to conventional diesel buses. Obtained average external costs of CO2 emissions per 100 bus-kms show to what extent their changes are a result of changes of external costs of CO2 emissions and to what extent they are due to changes of operating conditions on the road network.

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