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Driving cycles are typically used for estimation of vehicle fuel/energy consumption and CO2 emissions. In most of applications only the vehicle velocity vs. time profile is considered as a driving cycle, while a road slope is typically omitted. Since the road slope significantly impacts the fuel consumption, it should be included into realistic driving cycles for hilly roads. As a part of wider research of multidimensional driving cycle synthesis, this paper focuses on analysis of a broad city bus driving cycle dataset recorded in the city of Dubrovnik. The analysis is aimed at revealing the impact of road slope on velocity and acceleration distributions, and clustering the recorded data into several groups reflecting various driving and traffic congestion characteristics. Finally, the Markov chain method is employed to synthesize 3D driving cycles for the selected data clusters, where the Markov chain states include vehicle velocity, vehicle acceleration, and road slope.

Waste heat recovery based on an Organic Rankine Cycle is a technology proposed for the reduction of the fuel consumption of heavy-duty vehicles. This technology is currently not simulated by VECTO, the tool used in Europe to certify the fuel consumption and CO2 emissions of new heavy-duty vehicles. In this work, a class 5 lorry equipped with a prototype Organic Rankine Cycle system is tested on the chassis dyno during steady state and transient driving cycles, with the waste heat recovery enabled and disabled. The waste heat recovery system enabled a brake specific fuel consumption reduction of 3.1% over the World Harmonized Vehicle Cycle, 2.5% during the official EU Regional Delivery Cycle, and up to 6.5% at certain engine operating points during the fuel consumption mapping cycle. A model of the vehicle was created in VECTO based on the experimental data. The fuel consumption map of the engine with and without the Organic Rankine Cycle was derived from the steady-state experiments.

We investigate tradeoffs between the airflow strategies related to engine cooling and the aerodynamic-enabled fuel savings created by platooning. By analyzing air temperatures, engine temperatures and cooling air flow at different platoon distances, we show the thermal impact to the engine from truck platooning. Previously, we collected wind and thermal data for numerous heavy-duty truck platoon configurations (gaps ranging from 4 to 87 meters) and reported the significant fuel savings enabled by these configurations. The fuel consumption for all trucks in the platoon were measured using the SAE J1321 gravimetric procedure as well as calibrated J1939 instantaneous fuel rate while travelling at 65 mph and loaded to a gross weight of 65,000 lb.

Connectivity and autonomy in vehicles promise improved efficiency, safety and comfort. The increasing use of embedded systems and the cyber element bring with them many challenges regarding cyberattacks which can seriously compromise driver and passenger safety. Beyond penetration testing, assessment of the security vulnerabilities of a component must be done through the design phase of its life cycle. This paper describes the development of a benchtop testbed which allows for the assurance of safety and security of components with all capabilities from Model-in-loop to Software-in-loop to Hardware-in-loop testing. Environment simulation is obtained using the AV simulator, CARLA which provides realistic scenarios and sensor information such as Radar, Lidar etc. MATLAB runs the vehicle, powertrain and control models of the vehicle allowing for the implementation and testing of customized models and algorithms.

Maintaining the fuel temperature and fuel system components below certain values is an important design objective. Predicting these temperatures is therefore one of the key parts of the vehicle’s thermal management process. One of the physical processes affecting fuel tank temperature is fuel vaporization, which is controlled by the vapor pressure in the tank, fuel composition and fuel temperature. Models are developed to enable the computation of the fuel temperature, fuel vaporization rate in the tank, fuel temperatures along the fuel supply lines, and follow its path to the charcoal canister and into the engine intake. For diesel fuel systems where a fuel return line is used to return excess fluid back to the fuel tank, an energy balance will be considered to calculate the heat added from the high-pressure pump and vehicle under-hood and underbody.

Reliability and cost effectiveness of electronics demands its usage in all the wings of science and technology. Thus an attempt was made in this work to investigate the potential of using electronics for injecting primary fuel for the compression ignition engine used by farmers for agricultural purpose. In the first phase of the work, a new Electronic Control Unit (ECU) for primary fuel injection was developed and tested for its repeatability on fuel injection quantity for the different input voltages. Test engine was developed and tested under various load condition for its performance, emission, and combustion characteristics with neat diesel and Waste Cooking Oil Methyl Esters (WCOME) as baseline readings in the second phase of the work. In the third phase of work, the developed engine was modified to operate in duel fuel mode with developed ECU. In this work, ethanol was chosen as primary fuel due to its availability and less toxic nature as compared to other green fuels.

The joint forces and moments applied to the joints in an air suspension system in truck are important input loads for lightweight and fatigue analysis of bushings, air spring brackets, torque arms and trailing arms. In order to derive a reliable solution of joint forces and moments, engineers will generally use Multi Body Dynamics (MBD) simulation software, like ADAMS, which can save time in product development cycle. Taking an air suspension in truck as a study example, a 2-dimensional quasi-static model of an air suspension, whose stiffness of air spring and bushing is nonlinear, is established in ADAMS environment. After that, simulations are performed at the typical and extreme working condition respectively, and the results are compared with another three cases. Case I assumes that the stiffness of air spring is linear but the stiffness of bushings, including torsion and radial stiffness, are nonlinear.

The deformation of injector components cannot be disregarded as the pressure of the system increases. Deformation directly affects the characteristics of needle movement and injection quantity. In this study, structural deformation of the nozzle, the needle and the control plunger under different pressures is calculated by a simulation model. The value of the deformation of injector components is calculated and the maximum deformation location is also determined. Furthermore, the calculated results indicates that the deformation of the control plunger increases the control chamber volume and the cross-section area between the needle and the needle seat. A MATLAB model is established to The influence of structural deformation on needle movement characteristics and injection quantity is investigate by a numerical model. The results show that the characteristic points of needle movement are delayed and injection quantity increases due to the deformation.

With the continuous development of various technologies in the field of electric vehicles, more and more mature products are put into the market. Among them, electric commercial vehicle has been supported by many preferential policies because of its wide use and high energy utilization and has developed rapidly in recent years. At present, the electric drive-train systems of commercial vehicles can be divided into motor direct drive, integrated el-axle and distributed e-wheel drive. The first type only uses motor to replace the engine, and the other parts have little change. This method has low transmission efficiency and loose structure, which is a temporary transition scheme. The drive types of integrated E-axle and distributed E-wheel have their own advantages and disadvantages, which way to become the mainstream of the future have not yet been decided.

Diesel Cylinder Deactivation (CDA) has been shown in previous work to increase exhaust temperatures, improve fuel efficiency, and reduce engine-out NOx for engine loads up to 3 bar BMEP. The purpose of this study is to determine whether or not the turbocharger needs to be altered when implementing CDA on a diesel engine. This study investigates the effect of CDA on exhaust temperature, fuel efficiency, and turbocharger performance in a 15L heavy-duty diesel engine under low-load (0-3 bar BMEP) steady-state operating conditions. Two calibration strategies were evaluated. First, a “stay-hot” thermal management strategy in which CDA was used to increase exhaust temperature and reduce fuel consumption. Next, a “get-hot” strategy where CDA and elevated idle speed was used to increase exhaust temperature and exhaust enthalpy for rapid aftertreatment warm-up.

This paper describes the work performed in predicting and measuring the contribution of oil churning to the no-load losses of a commercial truck axle at typical running speeds. A computational fluid dynamics (CFD) analysis of the churning losses was conducted. The CFD model accounts for design geometry, operating speed, temperature, and lubricant properties. The model calculates the oil volume fraction and the torque loss caused by oil churning due to the viscous and inertia effects of the fluid. CFD predictions of power losses were then compared with no-load measurements made on a specially developed, dynamometer-driven test stand. The same axle used in the CFD model was tested in three different configurations: with axle shafts, with axle shafts removed, and with ring gear and carrier removed. This approach to testing was followed to determine the contribution of each source of loss (bearings, seals, and churning) to the total loss.

Truck manufacturers across the globe are developing new design concepts to tackle the higher raw material cost, increased weight, and process variations. Robust design simulations are performed to figure out reliable and cost-effective designs insensitive to the variations in geometric, shape, and material properties. A new robust design approach is evaluated along with traditional nominal design analysis. A case study of a heavy-duty truck radiator is presented using the new robust design approach. As a first step, a finite element (FE) model of the radiator is modeled and nominal finite element analysis (FEA) of deformation and baseline stress responses are calculated. Random simulation is performed to capture the uncertainty and design variations due to the geometric, material, and shape. Random design generators such as Monte Carlo method are deployed, and they populate around 250 random designs for each of the design variables.

This paper describes and compares different powertrain configurations for the retrofit of a heavy-duty Class 8 truck, powered by a 12.6 liters diesel engine. The engine is firstly equipped with an electrification-oriented organic Rankine cycle (ORC) system and then coupled to a traction electric machine into a hybrid powertrain. An electrification-oriented ORC system can produce enough energy to cover the ancillary loads, which in long-haul applications for freight transportation are quite demanding. Nevertheless, only powertrain hybridization can achieve significant improvements in the overall system efficiency. Both systems may thus be implemented in the same vehicle, but an efficiency improvement is guaranteed only if the system is carefully managed so as to reach a trade-off between the requirements and potential benefits of the ORC system and those of the hybrid powertrain.

The present study looks into different possibilities for tribological optimization of the piston/bore system in heavy duty diesel engines. Both component rig tests and numerical simulations are used to understand the roles of surface specifications, ring pack, and lubricant in the piston/bore tribology. Run-in dynamics, friction, wear and combustion chamber sealing are considered. The performance of cylinder liners produced using a conventional plateau honing technology and a novel mechanochemical surface finishing process - ANS Triboconditioning® - is compared and the importance of in-design “pairing” of low-viscosity motor oils with the ring pack and the cylinder bore characteristics in order to achieve maximum improvement in fuel economy without sacrificing the endurance highlighted. A special emphasis is made on studying morphological changes in the cylinder bore surface during the honing, run-in and Triboconditioning® processes.

The mountainous roads are very complex and changeable. When commercial vehicles are driving in mountain areas, the using of brakes can not only reduce the fuel economy, but also increase the brake wear. The aim of this system is utilizing the terrain changes of mountainous roads to guide the driver to control the accelerator pedal reasonably through the mutual transformation of kinetic energy and gravitational potential energy for reducing the energy loss caused by braking on downhill road. The theoretical control points of releasing the accelerator pedal on the uphill road are determined based on the road digital elevation model (DEM) information and the vehicle dynamic model.

The steering system of commercial vehicle is asymmetrical to left side and rightside, this causes vehicle pull during braking application. This directly affects the safety of the driver and vehicle ride & handling performance. In a similar way, the asymmetrical suspension parameter unintentionally set during vehicle assembly arealso major contributors for creating a vehicle pull. After application of brake force, the tire contact patch creates a moment about the kingpin axis. However, this moment generated is different on left and right-side due to asymmetrical design parameters resulting in vehicle deviation from its intended path. A large deviation may lead to on road accidents. Some of the major factors which are responsible for the vehicle pulling phenomenon are the asymmetrical steering system compliance, asymmetrical suspension geometry, tire, braking system, road camber etc.

Adopting a low compression ratio (LCR) is a viable approach to meet the stringent emission regulations since it can simultaneously reduce the oxides of nitrogen (NOx) and particulate matter (PM) emissions. However, significant shortcomings with the LCR approach include higher unburned hydrocarbon (HC) and carbon monoxide (CO) emissions and fuel economy penalties. Further, poor combustion stability of LCR engines at cold ambient and part load conditions may worsen the transient emission characteristics, which are least explored in the literature. In the present work, the effects of implementing the low compression ratio (LCR) approach in a mass-production light-duty vehicle powered by a single-cylinder diesel engine are investigated with a major focus on transient emission characteristics.

Global emission, rapid exhaustion of oil reserves and stern emissions protocols force us to seek alternative fuels for heavy duty diesel engines. Assessing the influence of Gasoline and JP-8 fuels on the engine performance and gaseous emissions of heavy-duty diesel engines is essential. Multi-fuel strategy program is required for the both, combat vehicles and highways commercial vehicles to optimised the fuel availability. With the Gasoline and JP-8 fueled diesel engine, penalties of fuel economy are well known. Experimental evaluation has confirmed that Gasoline and JP-8 fuels have great potential in reducing NOx emissions. Present study focuses on the effect of engine performance and emission by using Gasoline and JP-8 fuels in heavy duty military engine. NOx and nanoparticles emissions reduction were assessed. EGR is a better technique to reduce NOx.

To reduce exhaust emissions in commercial vehicles, hydrogen, as a carbon-free fuel, is a reasonable alternative to conventional fuels. In order to circumvent the current problem of hydrogen availability, the use of a gas engine for heavy duty vehicles (HDV), which is able to operate with pure compressed natural gas (CNG), pure hydrogen as well as any mixture of these both gases, is sensible. For this purpose, an operating concept for a gas engine was developed, which is able to operate with an arbitrary hydrogen-natural gas mixture ratio. Therefore, the mixture formation of a hydrogen-natural gas-air mixture was analyzed in a 3D CFD simulation. The results for pure hydrogen and pure CNG operation show a very good homogenization of the fuel distribution at the point of ignition when an outward-opening injector was used.

Automobile industry is facing challenges in the field of technological innovation and achieving minimum Total Cost of Ownership (TCO) despite rise in fuel prices. To overcome these challenges is certainly a challenging task. In doing so, automobile sector is mainly focused on passenger safety, comfort, reliability, meeting stringent emission norms, and above all reducing the vehicle fuel consumption. Referring to the Paris climate agreement, and India’s commitment to reduce the CO2 intensity by 33% - 35% by 2030 below the 2005 levels [1], it is imperative to lay down strong policies and procedure to curb the fuel consumption to contribute for reduction in carbon foot print and oil imports. Transportation sector is majorly responsible for the GHG Emission of which the CO2 emission from commercial vehicles is nearly 73% [2], although the total sales of commercial vehicles are around 4% of cumulative vehicle sales.