Vehicle functional requirements, emission regulations, and thermal limits all have a direct impact on the design of a powertrain cooling airflow system. Given the expected increase in emission-related heat rejection, suppliers and vehicle manufacturers must work together as partners in the design, selection, and packaging of cooling system components. The goal of this two-day course is to introduce engineers and managers to the basic principles of cooling airflow systems for commercial and off-road vehicles.
This course explores the design and performance of battery technologies used in today’s battery-electric vehicles. It focuses on the skills required to define a battery pack design, how battery packs are manufactured, and tests required before entering the market. Participants will leave the course equipped with tools to understand vehicle battery specifications and be able to extract the useful information from the large volume of electric vehicle content published daily. It also defines and analyzes fundamentals of battery operation and performance requirements for HEV, PHEV, EREV and full electric vehicle applications.
The global transportation industry is mandated to deliver significant reductions in Greenhouse Gas (GHG) emissions within the upcoming decades. The road freight sector in particular faces formidable challenges in terms of emission reduction, while maintaining/improving the performance of the current vehicles. In Europe this transition is being driven in part by specific CO2 legislation for heavy-duty vehicles (HDVs) and penalties for Original Equipment Manufacturers who miss these targets, while in the US these ambitions have been embedded within the EPA regulations. Europe currently has targets for CO2 reduction of 15% by 2025 and 30% by 2030 for new HDVs, likely increasing to 45% by 2030 and 90% by 2040. These targets have been set relative to the fleet average for the industry by truck category and are evaluated using the Vehicle Energy Consumption Calculation Tool (VECTO) to determine CO2 emissions for each unique vehicle configuration.
The benefits introduced by the replacement of conventional centrifugal pumps with volumetric machines for Internal Combustion Engines (ICEs) cooling were experimentally and theoretically proven in literature. In particular, Sliding Rotary Vane Pumps (SVRPs) ensure to achieve an interesting reduction of ICEs fuel consumption and CO2 emissions. Despite volumetric pumps are a reference technology for ICE lubrication oil circuits, the application in ICE cooling systems still not represent a ready-to-market solution. Particularly challenging is the case of Heavy-Duty ICE due to the wide operating range the pump covers in terms of flow rate delivered. Generally, SVRPs are designed to operate at high speeds to reduce machine dimensions and, consequently, the weight. Nevertheless, speed increase could lead to a severe penalization of pump performance since the growth of the friction losses.
Heavy duty truck engines are quite difficult to electrify, due to the large amount of energy required on-board, in order to achieve a range comparable to that of diesels. This paper considers a commercial 6-cylinder engine with a displacement of 12.8 L, developed in two different versions. As a standard diesel, the engine is able to deliver more than 420 kW at 1800 rpm, whereas in the CNG configuration the maximum power output is 330 kW at 1800 rpm. Maintaining the same combustion chamber design of the last version, a theoretical study is carried out in order to run the engine on Hydrogen, compressed at 700 bar. The study is based on GT-Power simulations, adopting a predictive combustion model, calibrated with experimental results. The study shows that the implementation of a combustion system running on lean mixtures of Hydrogen, permits to cancel the emissions of CO2, while maintaining the same power output of the CNG engine.
Today’s engines used in Agriculture, Mining and Construction are designed for robustness and cost. Here, the Diesel powertrain is the established mainstream solution, offering long operation times without refueling at any desired power rating. In view of the steps towards Carbon Neutrality by 2050 this segment of the Transportation Sector needs to reduce its CO2 emissions. Currently, the EU and US emissions legislations (EU Stage V / EPA Tier4) do not include a CO2 reduction scheme but is expected to change with the next update towards EU Stage VI / EPA Tier5 coming into effect 2030 and after. Larger power and operation range still require the use of renewable, liquid fuels or hydrogen. The cost-up of such fuels could be counterbalanced by more efficient engines in combination with a hybridized powertrain.
The societies around the world remain far from meeting the agreed primary goal outlined under the 2015 Paris Agreement on climate change: reducing greenhouse gas (GHG) emissions to keep global average temperature rise to well below 20°C by 2100 and making every effort to stay underneath of a 1.5°C elevation. Current emissions are rebounding from a brief decline during the economic downturn related to the Covid-19 pandemic. To get back on track to support the realization of the goal of the Paris Agreement, research suggests that GHG emissions should be roughly halved by 2030 on a trajectory to reach net zero by around mid-century.2 Although these are averaged global targets, every sector and country or market can and must contribute, especially higher-income and more developed countries bear the greater capacity to act. In 2020 direct tailpipe emissions from transport represented around 8 GtC02e, or nearly 15% of total emissions.
How are batteries used in the mobility industry? This three-week hybrid course introduces how batteries fit into the energy context and provides the fundamental knowledge and state-of-the-art insights into battery technologies. It will cover the key role of batteries as a tool for energy storage, the main components and parameters that characterize a battery, and the electrochemical phenomena that lie behind battery operation.
This paper presents optimal control co-design of a parallel electric-hydraulic hybrid powertrain, to be specific, for heavy-duty vehicles. A pure electric powertrain that consists of a rechargeable lithium-ion battery, a high-efficient electric motor, and a single or double-speed gearbox has drawn a keen interest in the automotive sector because of a growing demand for clean and efficient mobility. However, the state-of-the-art has shown limited capability and has not been able to meet the design requirements for heavy-duty vehicles of high-power demand such as a class 8 semi-trailer truck in terms of a driving range on one battery charge, battery charging time, and load-carrying capacity primarily due to the low power density of lithium-ion batteries and low energy conversion efficiency of electric motors at low speed.
In recent years, the electrification of commercial vehicles has emerged as a prominent and transformative trend within the industry. In contrast to their passenger car counterparts, commercial vehicles present distinctive challenges, necessitating solutions that address higher peak and continuous torque demands, unique packaging and interface prerequisites, and extended service life expectations. BorgWarner has committed to research and development aimed at tackling these multifaceted challenges. As a result of these efforts, BorgWarner has successfully engineered an innovative and well-balanced solution tailored specifically to the electrification of commercial vehicles. This paper describes the transformation of a Ford F-550 into a full-fledged electric vehicle employing an 800V electrical system architecture.
In Crank- Train system, the prime objective of crankshaft is to facilitate the transformation of reciprocating motion of connecting rod into rotational motion at flywheel end. Moreover, the contribution of mass from crankshaft is in the same order as of Flywheel assembly mass which accounts to approximately 40 to 50% of total mass of engine. Therefore, to accomplish the development of an efficient engine it is vital to optimize the crankshaft based on simulation parameters like balance rate, mass, torsional frequency, web shear stress etc. In the given work, crankshaft has been designed and developed for an Engine used in light duty commercial vehicle. The defined work demonstrates the application of 1D Simulation tool AVL Excite in development phase of the Engine. To establish an equilibrium between the weight and simulation guidelines, many iterations of models were evaluated and finally we were able to achieve mass reduction of nearly 8% from the base model.
A potential route to reduce CO2 emissions from heavy-duty trucks is to combine low-carbon fuels and vehicle electrification/hybridization. Hybridization offers the potential to downsize the engine. Although engine downsizing in the light-duty sector can offer significant fuel economy savings mainly due to increased part-load efficiency, its benefits and downsides in heavy-duty engines are less clear. As there has been limited published research in this area to date, there is a lack of a standardized engine downsizing procedure. This paper aims to use an experimentally validated one-dimensional phenomenological combustion model in a commercial engine simulation software GT-Power alongside turbocharger scaling methods to develop downsized engines from a baseline 6-cylinder (2.2 L/cyl, 26 kW/L) pilot-ignition, direct-injection natural gas engine.
Multi-motor powertrain topologies are playing an increasingly important role in the development of heavy duty battery electric trucks due to the changing driving requirements of these vehicles. The use of multiple motors and/or transmissions in a powertrain provides additional degrees of freedom for the energy management. The energy management system (EMS) consist of the gear selection strategy and torque split between the drive motors. The aim of the EMS is thereby to achieve high energy efficiency in motor and regenerative operation, while reducing the number of gear changes to ensure driving comfort. Ongoing research focuses on the energy management system of hybrid electric trucks, where the aim is to optimize the torque split between the combustion engine and the electric motor. In this paper, the EMS for an electric truck is described as a mixed-integer nonlinear control problem. This type of optimal control problem is notoriously difficult to solve.
By installing an automated mechanical transmission (AMT) on heavy-duty vehicles and developing a reasonable shift strategy in advance, it can reduce driver fatigue and eliminate technical differences among drivers, improving vehicle performance. However, after separating the driver from the decision-making process, the current shift strategy is limited to the current vehicle state and cannot effectively determine the road environment ahead. There may be a problem of cyclic shifting due to insufficient power when driving on a slope. To improve the adaptability of heavy-duty truck shift strategy to dynamic driving environments, this paper first analyzes the shortcomings of existing traditional heavy-duty truck shift strategies on slopes, and develops a comprehensive performance shift strategy incorporating slope factors. Based on this, forward-looking information is introduced to propose a predictive intelligent shift strategy that balances power and economy.
In electric vehicle applications, the majority of the traction motors can be categorized as Permanent Magnet (PM) motors due to their outstanding performance. As indicated in the name, there are strong permanent magnets used inside the rotor of the motor, which interacts with the stator and causes strong magnetic pulling force during the assembly process. How to estimate this magnetic pulling force can be critical for manufacturing safety and efficiency. In this paper, a full 3D magnetostatic model has been proposed to calculate the baseline force using a dummy non-slotted cylinder stator and a simplified rotor for less meshing elements. Then, the full 360 deg model is simplified to a 90deg quarter model based on motor symmetry to save the simulation time from 2 days to 4 hours. A rotor position sweep was conducted using the quarter model to find the max pulling force position. The result shows that the max pulling force happens when the rotor is 1mm overlapping with the stator core.
The transition towards electrification in commercial vehicles is getting more attention in recent years. This technical 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 housing a newly developed dual-motor eBeam axle that propels the rear wheels. Complementary additions encompass components such as an 800V/99 kWh battery pack, advanced SiC inverters, an 800V HVAC system, and a DC fast charging system. Central to this study is the control system governing the converted vehicle, prioritizing drivability, NVH suppression, and energy optimization. Evident improvements in responsiveness and reduced noise emission underscore the efficacy of the BEV's design.
In recent years, with the development of computing infrastructure and methods, the potential of numerical methods to reasonably predict aerodynamic noise in compressors has increased. However, aerodynamic acoustic modeling of complex geometries and flow systems is currently immature, mainly due to the greater challenges in accurately characterizing turbulent viscous flows. Therefore, recent advances in aerodynamic noise calculations for automotive turbocharger compressors were reviewed and a quantitative study of the effects for turbulence modeling (Shear-Stress Transport (SST) and Detached Eddy Simulation (DES)) and time-steps (2°and 4°) in numerical simulations on the performance and acoustic prediction of a compressor under full operating conditions was investigated. The results showed that for the compressor performance, the turbulence models and time-step parameters selection were within 1.5% error of the simulated and measured values for pressure ratio and efficiency.
Tanks play a pivotal role in swiftly deploying firepower across dynamic battlefields. The core of tank mobility lies within their powertrains, driven by diesel engines or gas turbines. To better understand the benefits of each power system, this study uses geo-location data from the National Training Center (NTC) to understand the power and energy requirements from a main battle tank over an 18-day rotation. This paper details the extraction, cleaning, and analysis of the geo-location data to produce a series of representative drive cycles for an NTC rotation. These drive-cycles serve as a basis for evaluating powertrain demands, chiefly focusing on fuel efficiency. Notably, findings reveal that substantial idling periods in tank operations contribute to diesel engines exhibiting notably lower fuel consumption compared to gas turbines. Nonetheless, gas turbines present several merits over diesel engines, notably an enhanced power-to-weight ratio and superior power delivery.
Ammonia is one of the carbon-free alternatives considered for power generation and transportation sectors. But ammonia’s lower flame speed, higher ignition energy, and higher nitrogen oxides emissions are challenges in practical applications such as internal combustion engines. As a result, modifications in engine design and control and the use of a secondary fuel to initiate combustion such as natural gas are considered for ammonia-fueled engines. The higher-octane number of methane (the main component in natural gas) and ammonia allows for higher compression ratios, which in turn would increase the engine's thermal efficiency. One simple approach to initiate and control combustion for a high-octane fuel at higher compression ratios is to use a spark plug. This study experimentally investigated the operation of a heavy-duty compression ignition engine converted to spark ignition and ammonia-methane blends.