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Society is moving towards climate neutrality where hydrogen fuelled combustion engines (H2 ICE) could be considered a main technology. These engines run on hydrogen (H2) so carbon-based emission are only present at a very low level from the lube oil. The most important pollutants NO and NO2 are caused by the exhaust aftertreatment system as well as CO2 coming from the ambient air. For standard measurement technologies these low levels of CO2 are hard to detect due to the high water content. Normal levels of CO2 are between 400-500 ppm which is very close or even below the detection limit of commonly used non-dispersive-infrared-detectors (NDIR). As well the high water content is very challenging for NOx measuring devices, like chemiluminescence detectors (CLD), where it results in higher noise and therefore a worse detection limit. Even for Fourier-transformed-infrared-spectroscopy-analysers (FT-IR) it is challenging to deal with water content over 15% without increased noise.

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.

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.

The present study discusses about the determination of the Seal drag force in the application where elastomeric seal is used with metallic interface in the presence of different fluids. An analytical model was constructed to predict the seal drag force and experimental test was performed to check the fidelity of the analytical model. A Design of Experiment (DoE) was utilized to perform experimental test considering different factors affecting the Seal drag force. Statistical tools such as Test for Equal Variances and One way Analysis of Variance (ANOVA) were used to draw inferences for population based on samples tested in the DoE test. It was observed that Glycol based fluids lead to lubricant wash off resulting into increased seal drag force. Additionally, non-lubricated seals tend to show higher seal drag force as compared to lubricated seals. Keywords: Seal Drag, DoE, ANOVA

The cylinder bore in an engine block is deformed under the assembling stress of the cylinder head and thermal stress. This distortion exacerbates the piston skirt friction and piston slap. Through a numerical and experimental study, this article analyzes the effect of an optimized bore profile on the engine performance. The piston skirt friction was estimated in a three-dimensional elastohydrodynamic (EHD) friction analysis. An ideal cylindrical bore under the rated load condition was assumed as the optimal bore profile that minimized the piston skirt friction without compromising the piston slap. The simulation study revealed that secondary motion of the piston immediately after firing the top dead center can be mitigated by narrowing the piston–bore clearance at the upper position of the cylinder.

Polymer electrolyte membrane (PEM) fuel cells will play a crucial role in the decarbonization of the transport sector, in particular for heavy duty applications. However, performance and durability of PEMFC stacks is still a concern especially when operated under high power density conditions, as required in order to improve the compactness and to reduce the cost of the system. In this context, the optimization of the geometry of hydrogen and air distributors represents a key factor to improve the distribution of the reactants on the active surface, in order to guarantee a proper water management and avoiding membrane dehydration.

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.

Crankshaft bearings function to maintain the lubrication oil films needed to support crankshaft journals in hydrodynamic regime of rotation. Discontinuous oil films will cause the journal-bearing couple to be in a mixed or boundary lubrication condition, or even a bearing seizure or a spun bearing. This condition may further force the crankshaft to break and an engine shutdown. Spun bearings have been identified to be one of the top reasons in field returned engines. Excessive investigations have found large, embedded hard debris particles on the bearings are inevitably the culprit of destroying continuity of the oil films. Those particles, in particular the suspicious steel residues, in the sizes of hundreds of micrometers, are large enough to cause oil film to break, but rather fine and challenging for materials engineers to characterize their metallurgical features. This article presents the methodology and steps of debris analyses on bearings at different stages of engine build.

The need for even more efficient internal combustion engines in the road transportation sector is a mandatory step to reduce the related CO2 emissions. In fact, this sector impacts significantly on greenhouse gases worldwide, and the path toward hybrid and electric powertrains has just begun. In particular, in heavy-duty vehicles the full electrification of the powertrain is far to be considered as a really feasible alternative. So, internal combustion engines will still play a significant role in the near/medium future. Hence, technologies having a low cost to benefits (CO2 reduction) ratio will be favorably introduced in existing engines. Thermal management of engines is today a recognized area of research. Inside this area, the interest toward the lubricant oil has a great potential but not yet fully exploited. Engine oil is responsible of the mechanical efficiency of the engine which has a significant potential of improvement.

In this paper, we present a novel algorithm designed to accurately trigger the engine coolant flow at the optimal moment, thereby safeguarding gas-engines from catastrophic failures such as engine boil. To achieve this objective, we derive models for crucial temperatures within a gas-engine, including the engine combustion wall temperature, engine coolant-out temperature, engine block temperature, and engine oil temperature. To overcome the challenge of measuring hard-to-measure signals such as engine combustion gas temperature, we propose the use of new intermediate parameters. Our approach utilizes a lumped parameter concept with a mean-value approach, enabling precise temperature prediction and rapid simulation. The proposed engine thermal model is capable of estimating temperatures under various conditions, including steady-state or transient engine performance, without the need for extra sensors.

The Insurance Institute for Highway Safety (IIHS) introduced its updated side-impact ratings test in 2020 to address the nearly 5,000 fatalities occurring annually on U.S. roads in side crashes. Research for the updated test indicated the most promising avenue to address the remaining real-world injuries was a higher severity vehicle-to-vehicle test using a striking barrier that represents a sport utility vehicle. A multi-stiffness aluminum honeycomb barrier was developed to match these conditions. The complexity of a multi-stiffness barrier design warranted research into developing a new dynamic certification procedure. A dynamic test procedure was created to ensure product consistency. The current study outlines the process to develop a dynamic barrier certification protocol. The final configuration includes a rigid inverted T-shaped fixture mounted to a load cell wall. This fixture is impacted by the updated IIHS moving deformable barrier at 30 km/h.

Effective design of the lubrication path greatly influences the durability of any transmission system. However, it is experimentally impossible to estimate the internal distribution of the automotive transmission fluid (ATF) to different parts of the transmission system due to its structural complexities. Hybrid vehicle transmission systems usually consist of different types of bearings (ball bearings, thrust bearings, roller bearings, etc.) in conjunction with gear systems. It is a perennial challenge to computationally simulate such complicated rotating systems. Hence, one-dimensional models have been the state of the art for designing these intricate transmission systems. Though quantifiable, the 1D models still rely heavily on some testing data. Furthermore, HEVs (hybrid electric vehicles) desire a more efficient lubrication system compared to their counterparts (Internal combustion engine vehicles) to extend the range of operation on a single charge.

Using the recycled waste oils are to be focused for the protection of environment by reducing the land pollution and disposal costs. This study is to use the recycled waste engine oil, waste cooking oil and waste plastic oil along with Bio-butanol from the waste cut vegetables and fruits. Initially, properties and solubility were tested for choosing a suitable blend for fueling into diesel engine from various proportions. These three blends from the base of three waste oils are then tested by modifying and standard engine operating parameters for performance. The properties tests results as 18% of waste engine oil (by volume) with bio-butanol, 16% of waste cooking oil (by volume) with bio- butanol and 24% of waste plastic oil (by volume) with bio-butanol are found competent for fueling engine. These blends produces low efficiency in lower brake powers and the emissions of smoke, hydrocarbons and carbon monoxide are also higher during the operation under standard parameters.

Recent automobile engines are equipped with many devices that are driven by oil pressure. Generally, engine oil is used for oil pressure, and in addition to its conventional functions of lubrication and cooling, etc., it also plays an important role in accurately driving such devices. One of the factors that can interfere with the characteristics of engine oil is air contamination. Excessive air contamination can cause issues with driving devices. Although there are various factors that contribute to air contamination, this paper focuses on, and attempts to help predict, the air generated by engine oil falling and colliding with the surface of the oil in the oil pan as it returns from the top to the bottom of the engine. Using the particle method as the prediction method, the coupled Moving Particle Simulation (MPS) and Discrete Element Method (DEM) calculations were used to represent the generation of air.

Engine operation produces particles that contaminate the lubricating oil and can damage the engine's internal components. This paper presents a model for a three-coil inductive metal particle sensor and verifies the rationality and accuracy of the model by simulating the motion of a single spherical iron particle passing through the sensor. On this basis, the simulation of coupling double particles with different sizes, distances, and shapes is carried out. The study explores the influence of particle motion on the sensor-induced signal under various conditions. The research shows that when two particles pass through the sensor, the induced voltage signal will produce superposition when the distance between the two particles is small. The peak value of the induced voltage is 1-2 times the peak value of the induced voltage of a single particle. As the distance increases, the peak value of the induced voltage initially decreases, then slowly increases, and finally stabilizes.

Due to the global drive for carbon neutrality, passenger vehicle gasoline engines are transitioning to higher levels of electrification, such as hybrid electric vehicles and plug-in hybrid electric vehicles, HEVs and PHEVs. Compared with conventional internal combustion engine (ICE) vehicles, the HEV or PHEV engine whilst in ICE only operation, typically operates for multiple shorter periods, in turn the engine coolant and lubricant temperatures are lower. Conventional internal combustion engines are often able to yield valuable fuel economy benefits by selecting appropriate engine lubricating oils, typically employing reduced viscosity and suitable additives. There are commercial engine tests available for measurement, often in an engine test cell for precision. Steady state testing is also a simplified option. Such efforts require care, as the accurate measurement is technically and practically challenging.

Noise reduction is generally accomplished by applying appropriate noise control treatments at strategic locations. Noise control treatments consisting of poroelastic materials in layers are extensively used in noise control products. Sound propagation through poroelastic materials is governed by macroscopic material and geometric properties. Thus, a knowledge of material properties is important to improve the acoustical performance of the resulting noise control products. Since the direct measurement of these properties is cumbersome, these have been usually estimated indirectly from easily measurable acoustic performance metrics such as normal incidence sound transmission and/or absorption coefficient, measured using readily available impedance tube. The existing inverse characterization approaches fulfilled the estimation by curve fitting measured and predicted acoustic models.

The world is on a “take-make-waste,” linear-growth economic trajectory where products are bought, used, and then discarded in direct progression with little to no consideration for recycling or reuse. This unsustainable path now requires an urgent call to action for all sectors in the global society: circularity is a must to restore the health of the planet and people. However, carbon-rich textile waste could potentially become a next-generation feedstock, and the mobility sector has the capacity to mobilize ecologically minded designs, supply chains, financing mechanisms, consumer education, cross-sector activation, and more to capitalize on this “new source of carbon.” Activating textile circularity will be one of the biggest business opportunities to drive top- and bottom-line growth for the mobility industry.

Curbs are as key to automated driving system (ADS) navigation, operation, and safety as they are for human driven vehicles. The design, maintenance, and management of curbs and adjacent infrastructure can make the difference in whether ADS vehicles can pick up and deliver passengers and goods safely, efficiently, and effectively. Curbs may also be key to integrating ADS services with other forms of active and human-driven transportation. Benefits from accessibility, reduced emissions, and strong supply chains require that ADS vehicles be able to dock curbside in a manner that does not disrupt traffic or impede safe movement of people walking, biking, or using a mobility device. Automated Vehicles and Infrastructure Enablers: Curbs and Curbside Management addresses considerations regarding the curb with respect to pick up and drops for passengers and freight, as well as managing and designing both sides of the curb with respect to automated vehicles and other types of shared mobility.

The automobile is undergoing the biggest transformation of its 100-year history. Motivated by consumer desire for automobiles to integrate with their digital life and inspired by new electric vehicles (EVs) that routinely receive over-the-air software updates, traditional automakers are embarking on a journey to re-engineer the vehicle as a platform defined by software. The foundation of the shift is a complete re-design from a mechanical hardware-centric system to a cloud-connected, software-centric ecosystem where each function is executed via a service-oriented architecture. This is the basis of the software-defined vehicle (SDV). The Software-defined Vehicle and its Engineering Evolution: Balancing Issues and Challenges in a New Paradigm of Product Development examines the complex journey ahead for traditional manufacturers as they transition to this new software-defined system.