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Different tire models are applied in agricultural mobility, but the impacts on the ground are not completely known. Some models of industrial tires, with applications in construction machines, could meet the agricultural demand since there is a shortage offer exclusive models for agriculture. The aim of this research was to analyze in a Fixed Tire Testing Unit (FTTU), under controlled conditions, the performance of two tire types, the first for agricultural construction and the second for industrial construction on two different agricultural soils (two surfaces). The characteristics of the tires evaluated were: 620/75R26 (agricultural tire) and 23.5-25 (industrial tire). The soil used to simulate the agricultural surface were: Red Yellow Latosol and the Distroferric Red Nitosol, chosen because they are representative of agricultural areas in Brazil.

The demand for alternative technologies to power internal combustion engines is increasing every day, as companies seek sustainable solutions that aim not only at a cleaner environment, but also at tangible economic advantages such as reduced fuel consumption. In Brazil, a large fraction of transport modes, especially freight transport, uses diesel as fuel, which led government agencies to implement strict regulations for pollutant emissions, such as Euro VI in Europe and the Proconve P8 in Brazil. In this context, compressed natural gas (CNG) offers a mature, clean, sustainable alternative contributing to the reduction of pollutant emission. Thus, the main objective of this work is to evaluate performance parameters such as specific fuel consumption, efficiency and economic analysis for extra heavy trucks fueled by CNG as an alternative to diesel in real applications in the country's freight transport.

This paper presents the development of a validation criteria method for designing of spring brackets, wear pads and equalizers of a leaf spring suspension of a semi-trailer from the perspective of durability and peak loads. The method consisted of the application of a finite element model from strain data collected in the application test. The results obtained in the components during the trailer’s operation were converted into load through calibration curves. The stress-life method was adopted, correcting the mean stress by the Goodman criterion and with the calculation of accumulated damage using Palmgren-Miner with cycle counting by rainflow in the structures during the data acquisition path. The relation between damage accumulation and the life expectancy of the components, defined in a specific distance (mileage) was established. Basquin´s equation was also used.

The transport systems, as large energy consumers and important contributors to greenhouse (GHG), criteria pollutant and noise emissions worldwide, have been permanently challenged by the continuously increased stringent environmental standards to improve its energy efficiency, as well as to reduce its environmental footprint. Transit systems, which operates in urban areas, are particularly subjected to stringent environmental and efficiency regulations, given their proximity to large population concentrations, alongside the urban transport corridors. This is particularly true for bus transit systems, mostly powered by internal combustion engines (ICE), generally fueled with fossil diesel fuel.

In 2020, 3.6 million of heavy-duty vehicles operate in Brazil transporting 1,548 billion TKU goods and 2,372 million passengers every year. 45.1 billion of liters of Diesel are consumed per year emitting 185.3 million tons of CO2 to atmosphere. Transportation is one of largest sectors of society in CO2 emissions, being responsible of 8.6% of GHG. In Brazil, heavy vehicles predominantly are powered by fossil fuels. Huge efforts have been displayed by the scientific community to mitigate GHG emissions. Brazil has signed the term of COP 26 establishing a goal to reduce GHG emissions in 50% until 2030. Heavy duty vehicles are responsible of emitting 49.9% of CO2 of the transportation sector. The emissions standards of Brazilian legislations have decreased the limits of NOx, PM, CO in 75, 94 and 63% since 2000 were PROCONVE P2 have stabilized the first emissions limits for heavy-duty vehicles.

Compression ignition engines are widely used in the cargo and passenger transport sectors, this is due to their high energy efficiency and can operate with renewable fuels. The search for increased efficiency in internal combustion engines and reduced emissions are increasingly stringent, so to meet regulatory emission standards, new technologies are being studied and developed to reduce emissions generated by engines, in the case of diesel engines compression ignition, studies of techniques to reduce NOx and soot have been carried out. One of the techniques studied is the application of the DFI - Ducted Fuel Injection concept, which makes the fuel spray pass through a small cylindrical duct installed upstream of the injection orifice of the injector nozzle, thus improving the air/fuel, making it more homogeneous and allowing a more complete combustion. This work addresses a study of this application of DFI with different compression ratios.

Exterior design modifications have crucial importance on vehicle aerodynamics. Therefore, it makes one of the key parameters to achieve to reduce the fuel consumption in diesel-, CNG-, and hybrid-powered engines and increase the range of electric vehicles (EVs). The slightest change in the vehicle exterior design can directly affect the vehicle aerodynamics. Thus, four different parameters (front windshield angle, front diffuser angle, rear diffuser angle, and fillet [bending] on the rear and front top) are reviewed on a conceptual 12 m long bus which is to be designed at Anadolu Isuzu. Computational fluid dynamics (CFD) simulations become a source for comparative evaluations in these studies. Simulations are carried out for all different models with a realizable k-epsilon turbulence model and enhanced wall treatment wall function.

In recent years, there has been an overall reduction in greenhouse emissions in the European Union (EU); however, that is not the case for the transport industry where road transports are responsible for more than 70% of all the transports emissions. Transport by trucks and busses is responsible for a fourth of these greenhouse emissions, and a significant contributor to the energy consumption of these vehicles is the aerodynamic drag. A particular branch of truck transport is the transport of timber by the use of timber trucks. A significant difference to ordinary trucks is that the load of the timber truck affects the shape and hence its aerodynamic behavior. In Europe, these timber trucks travel at speeds of up to 80 km/h. At this speed, the aerodynamic drag accounts for around 20–30% per ton-km of the fuel consumption for these vehicles. In this paper computational fluid dynamics (CFD) is used to investigate and improve the aerodynamics of a loaded timber truck.

In most farm tractors through the middle of the 20th century, a pressed steel frame chassis is used as a supporting part of the tractor on which the engine, wheels, axle assemblies, transmission, steering mechanism, brakes, and suspension members were mounted together. Farm tractors generally used in the agricultural field experiences a variation in the load and vibrations, which leads to failure/fracture in the frame/chassis. In order to reduce the failure/fractures in the chassis/frame, high strength materials are used. Therefore, the main objective of the paper is to identify the best suitable high strength material and most suitable cross section for a mini tractor chassis, so as to make it very strong to bear the heavy loads and shocks received while working in the farms in static conditions. In the present work, ladder chassis is designed and analyzed with three different types of cross sections like C, I and Rectangular box type.

Primarily, Acoustic performance of muffler are evaluated by insertion loss (IL) and backpressure/restriction. Where Insertion loss is mainly depends upon proper selection of muffler volume, which is proportional to Engine Swept volume, along with internal design configuration, which drives the acoustic principle. Same time, meeting the vehicle level pass by noise (PBN) value as per regulatory norms and system level backpressure as per engine specification sheet are the key evaluating criteria of any good exhaust system. Here, a new Reactive/Reflective type muffler of tiny size have been designed for heavy commercial vehicle application, which is unique in shape and innovative to meet desire performance. In this design, mainly sudden expansion, sudden contraction, flow through perforation and bell-mouth flow phenomenon are used.

Vehicle pose estimation is a key technology for autonomous vehicles and a prerequisite for path planning and vehicle control. Visual localization has gradually attracted extensive attention from academia and industry due to its low cost and rich semantic information. However, the incremental calculation principle of the odometry inevitably leads to the accumulation of localization error with the travel distance. To solve this problem, we propose a position correction algorithm based on lightweight landmark map, and further compensate the localization error by analyzing the error characteristics. The proposed algorithm takes the stop lines on the road as landmarks, and pairs bag-of-word vectors with the positions of the corresponding landmarks. Once landmarks in the map are encountered and successfully associated, the position of the landmarks can be exploited to effectively reduce the drift of the odometry. We also present a reliable landmark map construction method.

Bus bunching usually occurs in high-frequency bus corridors with negative effects for the passengers and the service providers. In order to solve the problem of bus bunching, this work proposed a berth allocation scheme and a platoon-based eco-driving speed optimization model of intelligent connected bus platoon considering the deviation of the buses following the advisory curve and the fuel consumption. The model is based on the distance of interval between two adjacent stations in bus corridor, using IDM car-following model to control the safety distance between follower and leader in same bus platoon, and utilizing particle swarm algorithm to optimize the solution to obtain the optimal speed curve of leader, for the purpose of guiding platoons to smoothly move in the bus corridor to alleviate bunching.

In order to overcome the problems such as ignoring the lack of depth information in the process of perspective projection, or sensitive to surveillance video quality that the existing vehicle motion state solution methods based on video image, this paper presents a methodology for reconstructing traffic accident based on surveillance video and scene point cloud. Firstly, the 2D-3D corresponding points from surveillance video image and scene point cloud are used to estimate the camera spatial pose, and then the Camshift algorithm is used to track the vehicle features and obtain the sequence of vehicle feature pixels. Secondly, the vehicle feature spatial position analysis model is constructed to analysis vehicle feature spatial position sequence, next the vehicle trajectory information is obtained by polynomial function fitting, and the vehicle speed information is obtained by feature spatial position Euclidean distance.

Governments and regulatory agencies in North America are evaluating the nitrogen oxides (NOx) emissions of heavy-duty on-road vehicles to effectively regulate these emissions in order to improve public health and meet air quality requirements. This paper provides results from real-world Class 8 tractor-trailer truck activity and emissions data gathering conducted in the Northeast and Mid-Atlantic United States. Unlike some other areas of the United States (US), there is little available data on in-use operation and emissions performance from heavy-duty trucks in this region where temperatures can be consistently cold in winter.

Less weight, structural integrity, good dynamic behavior, material selection, performance & energy consumption are important parameters while designing A/C components for EV applications. Structural integrity and dynamic behavior of these components is predicted by conducting dynamic analysis of A/C unit under standard vibration load test conditions. Material selection is another important point while designing A/C and simulation helps designer for proper material selection at initial design stage. Achieving required cooling capacity with less compressor power is another important factor while designing A/C unit and this is done by proper design changes on condenser and evaporator side with proper compressor selection. For this, CFD analysis helps to predict the air flow accurately with the given design parameters.

Unfavorable climates, fatigue, safety & deprived sleep of driver’s leads to use of AC system for their quick thermal comfort during night with engine ON. This scenario is very critical from a human’s safety & vehicle functionality point of view. This also consumes an additional 10-15% of fuel requirements in AC running conditions. So, to address the social problems of driver’s sleep and pollution-free environment by reducing the use of fossil fuels, there is a need for alternative techniques for air cooling which work during engine OFF condition. Various alternative options for air cooling have been reviewed. Accordingly, the packaging flexibility of phase change material (PCM) technology makes it easy to implement, yet effective usage of large quantity stored PCM, needs optimization. This paper proposes a design of a hybrid air conditioning system for sleeper commercial vehicles using a combined conventional compression and phase change material.

Heating, ventilation and air conditioning systems play a crucial role in our day-to-day activities. With rise in global warming, leading to climate change, HVAC unit is the need of the hour. With average temperatures on the rise, it is quite imperative that the unit provides better thermal comfort to the passengers. Off-road vehicles like tractor, is also no exclusion. Tractor drivers have to experience adverse weather conditions out in the open field. Thus it is quite fundamental that sufficient airflow reaches every point inside the driver cabin, ensuring proper cool-down. To ensure proper distribution of airflow inside the cabin, optimization of HVAC unit needs to be properly carried out. The present study shows how an HVAC of an off-road vehicle is properly optimized with the help of Computational Fluid Dynamics. STAR-CCM+ v2021.2.1 is used as solver for the simulation.

This paper explains about the design & development of IHX for HCVs segment and vehicle level validation to get the actual benefits with this technology. Moreover, the data observed during vehicle testing also indicates the improvement in AC System Performance. This experiment was done on HCV platform vehicle with multiple actual test conditions with two designs of IHX. Final result shows the optimized AC system design to achieve better efficiency.

Indian Railways, often described as the “transport lifeline of the nation”, is the fourth largest railway network in the world, from suburbs to urban transit, the Indian rail network covers the length and breadth of the country. To make the journeys easier and memorable it is very much important to provide adequate comfort and easy access to every facilitates. For better comfort inside the coach as well as in the drivers’ cabin, air-conditioning system has to be quite effective and energy efficient. While it is too expensive to go with prototypes at the initial stage, numerical simulation comes very handy in helping and optimizing the unit and come out with viable design concept within very short time. The present study provides a methodology for the numerical simulation of a drivers’ cabin AC to determine the volumetric airflow rate. The unit is designed for the drivers’ cabin and it is mounted on roof.

Hybrid powertrain has been proven to be an effective fuel-saving technology in commercial vehicles, but many hybrid commercial vehicles still use conventional diesel engines, resulting in limited fuel savings. The main purpose of this study is to enhance the thermal efficiency of a dedicated hybrid diesel engine focusing on the characteristic operating conditions. Via fundamental thermodynamics process analysis of internal combustion engine, steel piston with high compression ratio, air system involving two-stage turbocharger(2TC) with an intercooler, and late intake valve closing(IVC) timing are proposed to improve the thermal efficiency of the engine. Experimental results show that high compression ratio and lower thermal conductivity of the combustion chamber surface lead to lower heat release rates, requiring optimization of piston profile to accelerate the mixing rate. Besides, high compression ratio also leads to higher mechanical losses.