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Planning for charging in transport missions is vital when commercial long-haul vehicles are to be electrified. In this planning, accurate range prediction is essential so the trucks reach their destinations as planned. The rolling resistance significantly influences truck energy consumption, often considered a simple constant or a function of vehicle speed only. This is, however, a gross simplification, especially as the tire temperature has a significant impact. At 80 km/h, a cold tire can have three times higher rolling resistance than a warm tire. A temperature-dependent rolling resistance model is proposed. The model is based on thermal networks for the temperature at four places around the tire. The model is tuned and validated using rolling resistance, tire shoulder, and tire apex temperature measurements with a truck in a climate wind tunnel with ambient temperatures ranging from -30 to 25 °C at an 80 km/h constant speed.

This paper investigates the tire-road interaction for tires equipped with two different solid rubber material definitions within a Finite Element Analysis virtual environment, ESI PAMCRASH. A Mixed Service Drive truck tire sized 315/80R22.5 is designed with two different solid rubber material definitions: a legacy hyperelastic solid Mooney-Rivlin material definition and an Ogden hyperelastic solid material definition. The popular Mooney-Rivlin is a material definition for solid rubber simulation that is not built with element elimination and is not easily applicable to thermal applications. The Ogden hyperelastic material definition for rubber simulations allows for element destruction. Therefore, it is of interest and more suited for designing a tire model with wear and thermal capabilities.

Reconstruction of inline crashes between vehicles with a low closing speed, so-called “low speed” crashes, continues to be a class of vehicle collisions that reconstructionists require specific methods to handle. In general, these collisions tend to be difficult to reconstruct due primarily to the lack of, or limited amount of, physical evidence available after the crash. Traditional reconstruction methods such as impulse-momentum (non-residual damage based) and CRASH3 (residual damage based) both are formulated without considering tire forces of the vehicles. These forces can be important in this class of collisions. Additionally, the CRASH3 method depends on the use of stiffness coefficients for the vehicles obtained from high-speed crash tests. The question of the applicability of these (high-speed) stiffness coefficients to collisions producing significantly less deformation than experimental crashes on which they are generated, raises questions of the applicability.

Truck platooning is an emerging technology that exploits the drag reduction experienced by bluff bodies moving together in close longitudinal proximity. The drag-reduction phenomenon is produced via two mechanisms: wake-effect drag reduction from leading vehicles, whereby a following vehicle operates in a region of lower apparent wind speed, thus reducing its drag; and base-drag reduction from following vehicles, whereby the high-pressure field forward of a closely-following vehicle will increase the base pressure of a leading vehicle, thus reducing its drag. This paper presents a physics-guided empirical model for calculating the drag-reduction benefits from truck platooning. The model provides a general framework from which the drag reduction of any vehicle in a heterogeneous truck platoon can be calculated, based on its isolated-vehicle drag-coefficient performance and limited geometric considerations.

Tippers used for transporting blue metal, construction and mining material is designed with different types of load body to suit the material being carried, capacity and its application. These load bodies are constructed with high strength material to withstand forces under various operating conditions. Structural strength verification of load body using FEM is conducted, by modelling forces due to payload as a pressure function on the panels of the load body. The spatial variation of pressure is typically assumed. In discrete element method (DEM) granular payload material such as gravel, wet or dry sand, coal etc., can be modelled by accounting its flow and interaction with structure of load body for prediction of force/pressure distribution. In this paper, coupled FE-DEM is used for determining pressure distribution on loading surfaces of a tipper body structure of a heavy commercial vehicle during loading, unloading and transportation.

The mechanization of crops causes problems in soil structure as it causes compaction. Compaction can be severe depending on the type of tire adopted in the field. Producers are concerned with selecting wheelsets that harm the soil less and remembering to save resources when buying agricultural tires. Agricultural tires are more expensive than road tires, and truck tires can be an alternative for producers to save money. The present study evaluated the interaction between wheelset and ground in a fixed tire testing unit, comparing the impact of different tire models on bare ground. The 6 treatments performed consisted of 3 tire models (p1: road radial, composed of double wheelset - 2×275/80r22.5; p2: agricultural radial - 600/50r22.5; and p3: agricultural diagonal - 600/50-22.5) versus two contact surfaces, one rigid and the other with bare agricultural soil. Seven response variables were used to apply Regression analysis and descriptive statistics.

The SAE Recommended Practice establishes minimum performance requirements and related uniform laboratory test procedures for evaluating lateral (curb) impact collision resistance of all wheels intended for use on passenger cars and light trucks.

This SAE Recommended Practice establishes a uniform test procedure for evaluating performance of operator enclosure pressurization systems for construction, general-purpose industrial, agricultural, forestry, and specialized mining machinery as categorized in SAE J1116 for off-road, self-propelled work machines.

Abstract Since the steady-state computational fluid dynamics (CFD) Reynolds-averaged Navier–Stokes (RANS) turbulence models offer low-cost and sensible accuracy, they are frequently utilized for bluff bodies’ external aerodynamics investigations (e.g., upwind, crosswind, and shape optimization). However, no firm certainty is made regarding the best model in terms of accuracy and cost. Based on cost and accuracy aspects, four RANS turbulence models were studied, which are Spalart–Allmaras, realizable k-ε, RNG k-ε, and SST k-ω. Ahmed body with a 25° slant angle benchmark case was introduced for this investigation. Two grids were generated to satisfy the near-wall treatment of each turbulence model. All grid settings were proposed and discussed in detail. Fluid-structure analysis was performed on five different planes.

The Environmental Protection Agency (EPA), in partnership with Research Triangle Institute (RTI International) and Auto Research Center (ARC-Indy), have created digital geometries of commercially available heavy-duty tractor-trailers. The goal of this effort was to improve the agency’s understanding of aerodynamic modeling of modern trucks and to provide opportunities for more consistent engagement on computational fluid dynamics (CFD) analyses. Sleeper and day cab tractors with aerodynamic features and a 53-foot box trailer with aerodynamic technology options were scanned to create high-resolution geometries. The scanning process consisted of a combination of physical scanning with a handheld device, along with digital post-processing. The completed truck geometries are compatible with most commercial CFD software and are publicly available for modeling and analyses.

Brazil is significant grain (soy, corn, beans and rice) producer in the planet and the road transportation is needed even when rail and maritime mode is used. There are opportunities to improve the grain road transportation efficiency. This paper presents one opportunity which is the aerodynamic drag reduction and therefore the fuel and energy consumption reduction on grain road transportation. This paper will discuss some alternatives to reduce aerodynamic drag on such application considering Brazilian market regulation which has a low limit for front axle load (lower than European regulation for instance) and limit the total composition length. As an example of some alternatives to reduce drag there is the frontal area reduction and trailer to cab gap reduction. Some of those alternatives were implemented on a concept truck briefly presented on this paper, which was tested on a real application, this paper will illustrate some of those alternatives implemented.

The scope of this SAE Standard is the definition of the functional, environmental, and life cycle test requirements for electrically operated backup alarm devices primarily intended for use on off-road, self-propelled work machines as defined by SAE J1116 (limited to categories of (1) construction, and (2) general purpose industrial).

Materials play a key role in our day to day life and have shaped the industrial revolution to a great extent. Right selection of material for meeting a particular objective is the key to success in today’s world where the cost as well as sustainability of any equipment or a system have assumed greater significance than ever before. In automotive industry, materials have a definitive role as far as the mobility and safety is concerned. Materials that can absorb the required energy or impact can be manufactured through different manufacturing as well as metallurgical processes which involves appropriate heat treatment and bringing correct chemical compositions etc. However, they can also be formed by simpler methods such as combining certain materials together in the form of layered combinations to form light weight composites.

This SAE Recommended Practice establishes uniform Installation Parameters for desiccant Air Dryers for vehicles with compressed air systems.

This SAE Standard incorporates driving cycles that produce fuel consumption data relating to Urban, Suburban, and Interstate driving patterns and is intended to be used to determine the relative fuel economy among vehicles and driving patterns under warmed-up conditions on test tracks, suitable roads, or chassis dynamometers.1

Tire rolling resistance and temperature are the main parameters for the design and driving of the heavy-duty tires due to their effects on fuel economy and safety. In this paper, the influence of many factors on the tire rollingresistance and temperature is studied, including speed, inflation pressure and normal load; the relationship between rolling resistance properties and temperature of heavy tires is studied based on several experiments to explore the physical mechanism and characteristics of tire rolling resistance for heavy-duty vehicles. The effects of the driving time and temperature of the tire on the rolling resistance are performed on tire’s experimental platform, in which the empirical models involved in the driving time and temperature of the tire for the rolling resistance are established using the least square method for fitting the experimental data.

This paper presents a comprehensive investigation aimed to assess the effect of tire inflation pressure on the fuel consumption of a typical 4×4 off-road vehicle over unprepared soft terrains. For this purpose, a fourteen-degrees-of-freedom (14-DOF) full parametrized vehicle model is employed and numerically simulated in MATLAB/Simulink™ environment. This model is intended to consider all the rotational dynamics and compliances of all-wheel-drivetrain aggregates using SimDriveline™ toolbox including engine, transmission, differentials, shafts and wheels. Numerous simulations are carried out to examine both the tractive efficiency and fuel consumption considering all power losses in transmission, terrains and tire slippage over different operating conditions such as terrain’s mechanical properties, tire weight distribution and drivetrain configurations (open or locked center differential).

Proton Exchange Fuel Cells (PEMFCs) are considered one of the most prominent technologies to decarbonize the transportation sector, with emphasis on long-haul/long-range trucks, off-highway, maritime and railway. The flow field of reactants is dictated by the layout of machined channels in the bipolar plates, and several established designs (e.g., parallel channels, single/multi-pass serpentine) coexist both in research and industry. In this context, the flow behavior at cathode embodies multiple complexities, namely an accurate control of the inlet/outlet humidity for optimal membrane hydration, pressure losses, water removal at high current density, and the limitation of laminar regime. However, a robust methodology is missing to compare and quantify such aspects among the candidate designs, resulting in a variety of configurations in use with no justification of the specific choice.

Considerable effort is currently being focused on emerging vehicle automation technologies. Engineers are making great strides in improving safety and reliability, but they are also exploring how these new technologies can enhance energy efficiency. This study focuses on the changes in aerodynamic drag associated with coordinated driving scenarios, also known as “platooning.” To draw sound conclusions in simulation or experimental studies where vehicle speed and gaps are controlled and coordinated, it is necessary to have a robust quantitative understanding of the road load changes associated with each vehicle in the platoon. Many variables affect the drag of each vehicle, such as each gap length, vehicle type/size, vehicle order and number of vehicles in the platoon. The effect is generally understood, but there are limited supporting data in the literature from actual test vehicles driving in formation.

There have been many studies regarding the stability of vehicles following a sudden air loss event in a tire. Previous works have included literature reviews, full-scale vehicle testing, and computer modeling analyses. Some works have validated physics-based computer vehicle simulation models for passenger vehicles and other works have validated models for heavy commercial vehicles. This work describes a study wherein a validated vehicle dynamics computer model has been applied to extrapolate results to higher event speeds that are consistent with travel speeds on contemporary North American highways. This work applies previously validated vehicle dynamics models to study the stability of a five-axle commercial tractor-semitrailer vehicle following a sudden air loss event for a steer axle tire. Further, the work endeavors to understand the analytical tire model for tires that experience a sudden air loss.