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In recent years, deposit formation in the fuel systems for heavy-duty engines, using drop-in fuels, have become increasingly common. Drop-in fuels are particularly appealing because as they are compatible with existing engines, allowing for higher proportions of alternative fuels to be blended with conventional fuels. However, the precipitation of insoluble substances from drop-in fuels can result in fuel filter clogging and the formation of internal injector deposits, leading to higher fuel consumption and issues with engine drivability. The precise reasons behind the formation of these deposits in the fuel system remain unclear, with factors such as operating conditions, fuel quality, and fuel contamination all suggested as potential contributors. In order to reproduce and study the formation of internal injector deposits, for heavy-duty engines under controlled conditions, facilitating a more precise comparison to field trials, a novel injector test rig has been developed.

The objective of the project was to evaluate the energy efficiency of a hybrid electric tractor-semi-trailer combination prototype. The prototype was developed for log hauling application by integrating an existing tractor with an electric semi-trailer to improve fuel consumption and reduce greenhouse gas emissions. One of the conventional axles of the quad axle semi-trailer was replaced with a drive axle powered by an electric motor. Tests were conducted on a 105 km test route with a maximum difference in elevation of 355 m, including a hilly section with a length of 89 km. The results indicated fuel savings ranging from 10.5% to 14% per test run, with an average fuel savings of 12% when the electric drive axle was engaged. The hybrid electric tractor semi-trailer consumed 17.5% less fuel up-hill and 9.4% less down-hill. Throughout each test run, the battery’s state of charge fluctuated, averaging between 88% at the start and 52% at the end.

Combustion in conventional and advanced diesel engines is an intricate process that encompasses interaction among fuel injection, fuel-air mixing, combustion, heat transfer, and engine geometry. Manipulation of fuel injection strategies has been recognized as a promising approach for optimizing diesel engine combustion. Although numerous studies have investigated this topic, the underlying physics behind flame interactions from multiple fuel injections, spray-flame-wall interaction and their effects on reaction zones, and NOx/soot emissions are still not well understood. To this end, a computational fluid dynamics (CFD) study is performed to investigate the effects of pilot and post injections on in-cylinder combustion process and emissions (NOx and soot) formation in a heavy-duty (HD) diesel engine.

Catalyst heating operation in compression-ignition engines is critical to ensure rapid light-off of exhaust catalysts during cold-start. This is typically achieved by using late post injections for increased exhaust enthalpy, which retardability is constrained by acceptable CO and unburned hydrocarbons emissions, since they are directly emitted through the tailpipe due to the inactivity of the oxidation catalyst at these conditions. Post-injection retardability has shown to be affected by the cetane number of the fuel [SAE 2022-01-0483], but it is unclear how other fuel properties may affect the ability to retard the combustion. This study aims to understand the impact of the distillation characteristics of the fuel on the performance of catalyst heating operation and on post-injection retardability.

Abstract Engine brakes are more effective in braking a heavy-duty vehicle during deceleration compared to the traditional clutch-brake system. Therefore, commercial vehicle OEM’s along with regulations, demand the acclimatizing of engine brake (EB) system. To achieve this, it is equally important to adopt to variable valve actuation dynamic valvetrain (VT) system. To help develop these systems, Model Based Product Development approach is used primarily at Eaton. In current work, the effect of valve lash sensitivity on EB performance and VT dynamics is studied using multi physics GT-SUITE models. This helps to understand the impact of lash on valve lift opening, lift loss and overall VT system compliance. In addition to above VT dynamics, its effect on EB power is also studied. This is done using a medium duty 6-cylinder GT-POWER engine model developed from Fast Response Model (FRM) database.

With all the environmental concern of diesel fuelled vehicle, it is a formidable challenge to phase out them completely specifically from Heavy duty application. Most pragmatic solution lies in solutions which improves the fuel economy and reduce the carbon emission of existing diesel fuelled vehicle fleet and have economical & feasible for vast geographical extent of country. With implementation of BS VI emission norms across country from April 2020, supply of BS VI complied diesel fuel started and BS VI complied vehicles with upgraded engine technologies and after treatment devices have started to come which make present vehicle fleets heterogeneous with substantive number of BS IV vehicle. Beside improvement of engine technologies, existing BS IV vehicle fleet performance can be enhanced through improved fuel and lubricants solutions.

Electric and hybrid powertrains are steadily gaining popularity, showcasing their efficacy in reducing greenhouse gas emissions and pollution, particularly in urban environments. This also applies to medium and heavy-duty vocational trucks. Truck manufacturers have been expanding their electrified portfolio and some of them have already announced their plans to phase out fossil fuels. Vocational trucks are essential for the industry of commercial vehicles, represent an extremely heterogeneous class, and are often upfitted by third-party companies. In general, vocational trucks are designed for specific jobs. Typically, they are driven on short routes, but they may work for longer hours in comparison to freight transportation vehicles. Most importantly, among the broad category of vocational trucks, some vehicles greatly exploit power take-offs to drive auxiliary systems, like refuse trucks, utility trucks, cement trucks, and sweeper trucks.

Fighting climate change has become a major task worldwide. Alongside the United States and China, Europe is considered as one of the biggest greenhouse gases (GHG) emitters. Therefore, the European Union (EU) has set long term strategies to reduce emissions. One of the key energy sectors to emit greenhouse gases is transportation. In this context, EU has turned its eye toward cutting emissions from the transport sector and has recently put its stamp of approval on a reworked law banning all new sales of internal combustion engine (ICE) vehicles from 2035. Despite representing only 2% of the vehicles on the road, trucks account for more than a quarter of road transport emissions in the EU and have been increasing every year since 1990.

Light commercial vehicles are an indispensable element for the transport of people and the delivery of goods, especially on extra-urban and long-distance routes. With a view to sustainable mobility, it is necessary to think about hybridizing these vehicles to reduce the fuel consumption as well as greenhouse gas emissions and particulate matter. These types of vehicles are generally powered by diesel and travel many kilometers a day. On the other hand, the use of light commercial vehicles in battery electric vehicle (BEV) configuration has already been started but is not receiving widespread recognition. In this panorama, starting from a study already developed for the hybridization of a plug-in light commercial vehicle in Worldwide harmonized Light vehicles Test Cycle (WLTC) condition, the simulation analysis has been extended to the plug-in hybrid vehicle (PHEV) operating in real driving emission conditions (RDE).

Since signing the legally binding Paris agreement, fighting climate change has been an increasingly important task worldwide. One of the key energy sectors to emit greenhouse gases is transportation. Therefore, long term strategies all over the world have been set up to reduce on-road combustion emissions. One of the emerging alternative technologies to decarbonize the transportation sector is Mobile Carbon Capture (MCC). MCC refers to the on-board separation of CO2 from vehicle exhaust. To accurately assess this technology, a techno-economic analysis is essential to compare MCC abatement cost to alternative decarbonization technologies such as electric trucks. Adding to the system capital and operational costs, our study includes mass penalty costs, CO2 offloading and transport costs for different transport scenarios. To better relate to a single consumer (driver), the cost can be converted from euro per-tCO2 to euro per-trip or euro per-mile.

Vibrations in IC engines have a widespread effect on the operations of consumer and commercial vehicles, which not only affect the life and efficiency of the vehicle but also affect user comfort and nervous system of human body. This paper focuses on the comparative analysis of vibration and acoustic characteristics while utilizing fuels such as petrol and CNG. ADXL 335 3-axis accelerometer was employed to measure acceleration vs time data, which was then processed using MATLAB to obtain FFT and PSD plots. These plots thus obtained gave insights on dominating frequency as well as frequencies with maximum energy. Six different cases with different engine speeds and loading conditions are studied with analysis of all the different parameters such as sound pressure levels and mean and max cylinder pressure.

A method of overall modeling and step-by-step solution was proposed to verify and analyze the strength of the mount shell. First, a reliable finite element simulation model was established based on testing of the mechanical properties of rubber materials, constitutive model construction, and stiffness tests of the mounts. Second, the displacement of the mount system under preloading and crash loads was calculated separately through the modeling of the powertrain mount simulation, which provided accurate load conditions of the mount for the following work. Finally, the strength calculation and evaluation of the mount shell was completed with the quasi-static solution method. This calculation method could consider the influence of complex factors comprehensively, such as assembly load distribution, large deformation of rubber, and contact nonlinearity on the stress distribution of the mount shell.

The fast acceleration of GHG (CO2 in particular) emitted by human activities into the atmosphere is accelerating the average temperature increase of our globe causing heavy climate change. This phenomenon has triggered a strong pressure on GHG emission reduction in all the human activities including the transportation sector which contributes for the 29% to the total emissions in EU [1]. A mitigation to this tendency can come from synthetic fuels: when produced by using clean energy, they can be considered CO2 neutral. H2 is the building block of synthetic fuels and can be used in spark ignited engines where releases the energy accumulated during its production. This solution is particularly attractive for HD applications thanks to the high energy density. H2 can be burned in a quite wide range of λ, but staying on 2,2 the amount of engine out NOx will be low enough for the use on a 13L engine with a relatively simple aftertreatment system.

Nowadays, green hydrogen can play a crucial role in a successful clean energy transition, thus reaching net zero emissions in the transport sector. Moreover, hydrogen exploitation in internal combustion engines is favored by its suitable combustion properties and quasi-zero pollutant emissions. High flame speeds enable a lean combustion approach, which provides high efficiency and reduces NOx emissions. However, high airflow rates are required to achieve the load levels typical of heavy-duty applications. In this framework, the present study aims at investigating the required boosting system of a 6-cylinder, 13-litre heavy-duty spark ignition engine through 1D numerical simulation. A comparison among various architectures of the turbocharging system and the size of each component is presented, thus highlighting the limitations and potentialities of each architecture and providing important insights for the selection of the best turbocharging system.

The hydrogen engine is one of the promising technologies that enables carbon-neutral mobility, especially in heavy-duty on- or off-road applications. In this paper, a methodological procedure for the design of the combustion system of a hydrogen-fueled, direct injection spark ignited commercial vehicle engine is described. In a preliminary step, the ability of the commercial 3D computational fluid dynamics (CFD) code AVL FIRE Classic to reproduce the characteristics of the gas jet, introduced into a quiescent environment by a dedicated H2 injector, is established. This is based on two parts: Temporal and numerical discretization sensitivity analyses ensure that the spatial and temporal resolution of the simulations is adequate, and comparisons to a comprehensive set of experiments demonstrate the accuracy of the simulations. The measurements used for this purpose rely on the well-known Schlieren technique and use helium as a safe substitute for H2.

For the purpose of achieving carbon-neutrality in the mobility sector by 2050, hydrogen can play a crucial role as an alternative energy carrier, not only for direct usage in fuel cell-powered vehicles, but also for fueling internal combustion engines. This paper focuses on the numerical investigation of high-pressure hydrogen injection and the mixture formation inside a high-tumble engine with a conventional liquid fuel injector for passenger cars. Since the traditional 3D-CFD approach of simulating the inner flow of an injector requires a very high spatial and temporal resolution, the enormous computational effort, especially for full engine simulations, is a big challenge for an effective virtual development of modern engines. An alternative and more pragmatic lagrangian 3D-CFD approach offers opportunities for a significant reduction in computational effort without sacrificing reliability.

This study emphasizes the importance of CAE approach in optimizing EGR tube under vibrational load. EGR tube is a weak link in the EGR system and chances of failure due to vibration and relative displacement of mating parts, i.e., overhang or improper support at exhaust manifold, intake manifold, or EGR system. Consideration of the mating parts for the EGR tube is very important to get the realistic resonance frequencies, otherwise it could have some different results in the CAE, which will deviate from the reality. So, it’s important to study the dynamic response on the EGR tube, which needs to be taken care during the design phase. This paper aims to optimize the EGR tube under vibrational load by using CAE techniques and the industry experience as a product expertise. some critical parameter such as damping is very important during the CAE, which can be generated by doing the rigorous testing and how it affects the stress and correspondingly FOS.

Current GHG emissions are rebounding from an intermediate decline during the economic downturn caused by the Covid-19 pandemic. To get back on track to support the realization of the formulated goals of the Paris Agreement, scientific communities suggest that worldwide GHG emissions should be roughly halved by 2030 on a trajectory to reach net zero by around mid-century. Carbon neutrality imposes substantial changes in our energy mix. Hydrogen (H2) is considered to play a key role as a carbon-free and versatile energy carrier for all kinds of applications and use cases. Considering the high technological maturity of internal combustion engines (ICEs), the interest in ICEs powered by hydrogen as a CO2-free solution is rising worldwide. The content of this publication displays the necessary engineering steps to successfully convert a diesel-based engine to H2 DI operation.

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. 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 ICEs due to the wide operating range the pump covers in terms of flow rate delivered and pressure rise. 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 engines for long-haul trucks are quite difficult to electrify, due to the large amount of energy that should be stored on-board to achieve a range comparable to that of conventional fuels. In particular, this paper considers a stock engine with a displacement of 12.9 L, developed by the manufacturer in two different versions. As a standard diesel, the engine is able to deliver about 420 kW at 1800 rpm, whereas in the compressed natural gas configuration the maximum power output is 330 kW, at the same speed. Three possible alternatives to these fossil fuels are considered in this study: biodiesel (HVOlution by Eni), bio-methane and green hydrogen. While the replacement of diesel and compressed natura gas with biofuels does not need significant hardware modifications, the implementation of a hydrogen spark ignition combustion system requires a deep revision of the engine concept.