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On the path to decarbonizing road transport, electric commercial vehicles will play a significant role. The first applications were directed to the smaller trucks for distribution traffic with relatively moderate driving and range requirements, but meanwhile, the first generation of a complete portfolio of truck sizes is developed and available on the market. In these early applications, many compromises were accepted to overcome component availability, but meanwhile, the supply chain can address the specific needs of electric trucks. With that, the optimization towards higher usability and lower costs can be moved to the next level. Especially for long-haul trucks, efficiency is a driving factor for the total costs of ownership. Besides the propulsion system, all other systems must be optimized for higher efficiency. This includes thermal management since the thermal management components consume energy and have a direct impact on the driving range.

Heavy-duty vehicles equipped with polymer electrolyte membrane fuel cells (PEM-FC) are an environmentally friendly alternative to vehicles powered by internal combustion engines. A major challenge for heavy-duty fuel cell vehicles is the potential cooling deficit under high load conditions at high ambient temperatures. To solve this problem, a spray cooling system can be utilized, in which liquid water is sprayed on the main cooler at the front end of the vehicle. The evaporation of the sprayed liquid water results in an increased cooling power. In this paper, the recovery of liquid water within the cathode loop of a mobile PEM-FC system is presented and discussed. For this purpose, three different topologies of the cathode subsystem of the PEM-FC are investigated for recovering liquid water directly from the fuel cell exhaust gas. To obtain liquid water, vapor in the exhaust gas is cooled below the saturation temperature in an additional heat exchanger.

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.

In 2022 in the UK, the transport sector was the largest single contributing sector to greenhouse gas emissions, responsible 34% of all territorial carbon dioxide emissions [1]. In the UK there is growing uptake in zero emission powertrain technologies, with the most promising variants based on battery electric or hydrogen fuel cell electric configurations. Given the limited number of fuel cell electric buses currently in operation in Europe, vehicle models and simulations are one of the few methods available to estimate energy consumption and provide the necessary increased confidence in operating range. This paper investigates the impact of route characteristics, thermal demand and coefficient of performance of different heat source configurations on the operational energy consumption of fuel cell electric buses. Using a MATLAB/Simulink model, the total energy demand of a vehicle operating in different route/elevation profiles is considered.

Considering the current trend towards the electrification of commercial vehicles, the development of Beam eAxle solutions has become necessary. The utilization of an electric drive unit in heavy-duty solid axle-based commercial vehicles presents unique and demanding challenges. These include the necessity for elevated peak and continuous torque while meeting packaging constraints, structural integrity requirements, and extended service life. One such solution was developed by BorgWarner to address these challenges. This paper offers a comprehensive overview of the design and development process undertaken for this Dual Motor Beam eAxle system. This includes the initial comparison of various eAxle solutions, the specifications of components selected for this design, and the initial results from dyno and vehicle development.

In order to study the influence of engine silicone oil fan clutch on the performances of engine cooling system under different control strategies, a model of engine cooling system for light truck is established. The working characteristics of the silicone oil clutch and the measured performance parameters of the cooling system components are taken into account in our proposed model. Modeling methods for different silicone oil fan control strategies are also given. Using the established model, the performance parameters under different vehicle speeds, such as coolant temperature of engine outlet and power consumption of cooling fan, are calculated and analyzed. The in-suite measurement of the engine cooling system is carried out to get the temperatures of engine coolant inlet and outlet from engine ECU. The model is validated by the comparison between the calculation and the measured results.

To better understand the technical challenges of commercial vehicle electrification, BorgWarner converted a production Internal Combustion Engine (ICE) medium duty truck into a fully electrified vehicle. The resulting vehicle includes a newly developed dual-motor rear Beam eAxle driven by a pair of high-performance silicon carbide (SiC) inverters, an 800V battery system, and a new thermal management system customized for the electric vehicle. This paper will detail the conversion process along with the key components involved in the build. The resulting performance of the fully electrified commercial vehicle will be presented in comparison to the original production vehicle. The primary aim is to outline what is entailed in an electric vehicle conversion and to share the learnings gained throughout this build and development process.

Internal combustion engines are becoming ever more efficient as mankind seeks to mitigate the effects of climate change while still maintaining the benefits that a mechanized society has brought to the global economy. As peak values, mass production spark-ignition engines can now achieve approximately 40% brake thermal efficiency and heavy-duty truck compression-ignition engines can approach 50%. While commendable, the unfortunate truth is that the remainder gets emitted as waste heat and is sent to the atmosphere to no useful purpose. Clearly, if one could recover some of this waste heat for beneficial use then this is likely to become important as new means of mitigating fossil CO2 emissions are demanded. A previous study by the authors has identified that the closed Joule cycle (or complications of it beginning to approximate the closed Ericsson cycle) could reasonably be developed to provide a practical means of recovering exhaust heat when applied to a large ship engine.

The thermal behavior of the electric axle is an essential indicator which requires certain attention during the development process. Due to the complexity of heat generation mechanism and heat transfer boundary conditions, it is difficult to accurately predict the axle’s temperature, especially in real driving conditions. In this paper, a comprehensive 1D model is developed to simulate its heat transfer process effectively and accurately. The heat transfer model is developed based on the thermal network method, and the electric axle is divided into thermal mass according to its heat transfer characteristics. The heat generation model, which accounts for meshing loss, bearing loss, churning loss, and windage loss, exchanges heat flux and oil temperature information with the heat transfer model to take into account the effect of lubricating oil temperature on power loss.

Methanol is one of the most promising fuels for the decarbonization of the off-road and transportation sectors. Although methanol is typically seen as an alternative fuel for spark ignition engines, mixing-controlled compression ignition (MCCI) combustion is typically preferred in most off-road and medium-and heavy-duty applications due to its high reliability, durability and high-efficiency. In this paper, the potential of using ignition enhancers to enable methanol MCCI combustion was investigated. Methanol was blended with 2-ethylhexyl nitrate (EHN) and experiments were performed in a single-cylinder production-like diesel research engine, which has a displacement volume of 0.83 L and compression ratio of 16:1. The effect of EHN has been evaluated with three different levels (3%vol, 5%vol, and 7%vol) under low- and part-load conditions. The injection timing has been swept to find the stable injection window for each EHN level and load.

A major concern for a high-power density, heavy-duty engine is the durability of its components, which are subjected to high thermal loads from combustion. The thermal loads from combustion are unsteady and exhibit strong spatial gradients. Experimental techniques to characterize these thermal loads at high load conditions on a moving component such as the piston are challenging and expensive due to mechanical limitations. High performance computing has improved the capability of numerical techniques to predict these thermal loads with considerable accuracy. High-fidelity simulation techniques such as three-dimensional computational fluid dynamics and finite element thermal analysis were coupled offline and iterated by exchanging boundary conditions to predict the crank angle-resolved convective heat flux and surface temperature distribution on the piston of a heavy-duty diesel engine.

Off-road diesel engines remain one of the most significant contributors to the overall oxides of nitrogen (NOX) inventory and the California Air Resources Board (CARB) has indicated that reductions of up to 90% from current standards may be necessary to achieve its air quality goals. In recognition of this, CARB has funded a program aimed at demonstrating emission control technologies for off-road engines. This program builds on previous efforts to demonstrate Low NOX technologies for on-road engines. The objective was to demonstrate technologies to reduce tailpipe NOX and particulate matter (PM) emissions by 90 and 75%, respectively, from the current Tier 4 Final standards. In addition, the emission reductions were to be achieved while also demonstrating a 5 to 8.6% carbon dioxide (CO2) reduction and remaining Greenhouse Gas (GHG) neutral with respect to nitrous oxide (N2O) and methane (CH4).

The transition towards electrification in commercial vehicles has received more attention in recent years. This paper details the conversion of a production Medium-Duty class-5 commercial truck, originally equipped with a gasoline engine and 10-speed automatic transmission, into a battery electric vehicle (BEV). The conversion process involved the removal of the internal combustion engine, transmission, and differential unit, followed by the integration of an ePropulsion system, including a newly developed dual-motor beam axle that propels the rear wheels. Other systems added include an 800V/99 kWh battery pack, advanced silicon carbide (SiC) inverters, an upgraded thermal management system, and a DC fast charging system. A key part of the work was the development of the propulsion system controls, which prioritized drivability, NVH suppression, and energy optimization.

Commercial vehicle are exposed to harsh environment conditions like dust, mud, wind, rain, extreme sun and winter throughout. Apart from white goods and other conventional loading these vehicles also used in applications which involve Handling of Dirty Loads, Construction Raw materials, Mining Industry etc. which leads to fast deterioration of Interiors. Also, in most cases drivers are not the owners. Hence due to high cost of Cleaning at dealerships and low Product maintenance awareness amongst Commercial Vehicle Users, on Road Washing & Cleaning by riverside is common practice which leads to early deterioration of Interior trims. This paper deals with the retention of newness of soft trim parts such as headliner, wall trims and carpets. Causes of product deterioration and attributes which influence newness like product appeal, NVH, perceived quality, environmental impact, geometry retention over time etc. have been discussed in detail.

The automotive world is moving towards electric powertrain systems. The electric powertrain systems have emerged as a promising alternative to the conventional powertrain system. The performance of electric vehicle is highly dependent on operating temperature of electric and electronic components of the vehicle. All power electronics and electric components in EV generate heat during operation and it must be removed to prevent overheating of components. Higher temperatures raise safety concerns whereas lower temperatures deteriorate the performance of power electronics & electric components. These power electronics & electrical components perform efficiently and safely if operated within certain temperature range. This paper presents an advanced efficient cost-effective thermal technique for small commercial electric vehicle (SCEV) to improve the performance & life of major electric components.

Road infrastructure in India is being upgraded at a rapid pace. Quality of life of people has also improved significantly in the last decade. Such trends have significantly impacted design of commercial vehicles and vehicular systems in the country. This paper deals with the design and development of a modern futuristic instrument panel for trucks. Methodology to arrive at product features and solutions which retain their novelty and appeal for a longer term has also been illustrated. Regulatory scenario, modularity, HMI, Perceived Quality, Driver Comforts, evolving technologies, trends and materials are some of the considerations which have discussed in detail. International benchmarks and customer requirement have been analyzed for setting Performance targets. A digital approach for evaluating these considerations evolved during the design and development process has been elaborated in detail.

Automotive crash data analysis and reconstruction is vital for ensuring automotive safety. The objective of vehicle crash reconstruction is to determine the vehicle's motion before, during, and after the crash, as well as the impact on occupants in terms of injuries. Simulation approaches, such as PC CrashTM, have been developed to understand pre-crash and post-crash vehicle motion, rather than the crash phase behavior. Over the past few decades, crash phase simulations have utilized vehicle finite element models. While multibody simulation tools are suitable for crash simulations, they often require detailed crash test data to accurately capture vehicle behavior, which is not always readily available. This paper proposes a solution to this limitation by incorporating crash test data from databases, such as NHTSA, Global NCAP, consumer rating reports, and videos, along with a multibody-based approach, to conduct crash phase simulations.

Child crash injury protection in severe rear impact chiefly depends on how well the rear survival space bounded by the vehicle structure is maintained. Previous research and studies have shown the ill effects of front seatback collapse intruding into the rear child survival space from front with minor or no intrusions from the rear. This paper shows the child injury pattern and fatal injury mechanism for a rear impact crash with a severe compartment intrusion from the rear without any front seat occupant. Furthermore, it compares the injury outcome with a similar crash and severe intrusion in the presence of the front occupant employing a full-scale vehicle-to-vehicle crash test. A detailed real-world crash investigation is conducted to identify the injury mechanism and is compared with the outcome of similar severity rear impact vehicle-to-vehicle crash tests producing different injury patterns.

The brake systems are given top priority by automotive OEMs in the development of medium and heavy commercial trucks and buses, which can carry increased loads. When trucks and buses are travelling at high speeds or crossing downhill, during braking operations, the friction faces (brake drum and liner) experience a significant rise in temperature due to the conversion of kinetic energy into heat energy within seconds. This lowers the friction coefficient at the interface, resulting in distortions, thermal cracks, hub grease burning, and overheating. Drum brake system designs must be improved and optimized to dissipate more heat from the brake drum assembly and prevent brake failure. Nowadays advance transient numerical simulations assist in the design, development and optimization of the brake system to visualize 3D flow physics and temperature variations throughout the brake duty cycles. In the current study, different Cases of drum brakes to improve cooling efficiency are evaluated.

An accurate estimate of vehicle speed is essential for optimal anti-lock braking system (ABS) calculations. Currently, most vehicles including heavy-duty class 8 trucks mainly rely on wheel speed sensors (WSS) to estimate velocity. However, as soon as braking is applied, WSS become inaccurate for determining the velocity due to the longitudinal slip developed in the tires. Using the inertial measurement unit (IMU) to estimate vehicle speed allows for its use in conjunction with the WSS to accurately calculate the slip ratio at each tire. These slip ratio values can then be used as the main control variable in the ABS algorithm to utilize the grip available more fully at each tire, to improve stopping distance and controllability. A steady state braking analysis model is developed and validated against Federal Motor Vehicle Safety Standards (FMVSS) 121 60-0 mph stopping distance data for a loaded class 8 tractor semi-trailer combination.