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Vehicle manufacturers will need to overhaul current development methods used to guarantee emissions compliance with the introduction of more stringent emissions legislation. Climatic boundaries of temperature and altitude and in-service conformity mileage compliance will likely be extended alongside alterations to trip dynamics; this will require robust calibrations for emissions compliance. Consequently, assessing this vast array of scenarios will be impossible with physical testing of prototype vehicles and overseas climatic testing alone. To reduce reliance on physical testing for compliance, a frontloading vehicle and powertrain development programme has been established where road, chassis dynamometer, Engine-in-the-Loop (EiL) and digital twin virtual toolset methodologies are used.

Vehicle emissions and fuel economy in real-world driving conditions are currently under considerable scrutiny. Key to achieving optimum performance for a given hardware set and control scheme is a calibration that optimizes controller gains such that inputs are scheduled over the operating space to minimize emissions and maximize fuel economy. Generating a suitable calibration requires data that is both precise and accurate, this data is used to generate models that are deployed as part of the calibration optimization process. This paper evaluates the repeatability of typical steady-state measurements used for calibration of engine controllers that will ultimately determine vehicle level emissions for homologation include Real Driving Emissions (RDE). Stabilization requirements as indicated by three different measurements are evaluated and shown to be different within the same experiment, depending on the metric used.

The newly proposed Euro 7 emission standards have added regulations limiting ammonia emissions for gasoline vehicles. This paper proposes a new emissions-control strategy to satisfy the regulated ammonia emission levels, using deceleration cylinder cut-off (DCCO) to reduce or eliminate conventional deceleration fuel cutoff (DFCO) and the associated lean-rich excursions in the three-way catalyst during oxygen saturation and desaturation. The improved air-fuel ratio management closer to stoichiometry lowers the ratio of CO to NOx and thus the ammonia (NH3) formation rate inside catalytic converter. Tests show more than 80% reduction of ammonia emission on the WLTC drive cycle without increasing other regulated emissions.

March 2011, the Great East Japan Earthquake and subsequent Giant Tsunami caused insufficient nuclear reactor cooling at the Fukushima Daiichi Nuclear Power Station (1F), resulting in a catastrophe of hydrogen explosion. The development of long-term safe storage technology for high-dose radioactive fuel debris collected by the decommissioning of nuclear power plants is an urgent issue. Inside the storage canister, strong radiation from fuel debris decomposes water to generate hydrogen and oxygen. The research and development have been proceeding in order to secure safety by simply placing a catalyst in the canister for oxidizing hydrogen and returning it into water. The catalyst is called a Passive Autocatalytic Recombiner (PAR), and unlike catalysts for chemical plants, it is required to have robustness that can maintain its activity for more than 30 years in an environment where temperature, humidity, gas concentration, etc. cannot be controlled.

Gasoline direct-injection (GDI) engine technology improves vehicle fuel economy while decreasing CO2 emissions. The main drawback of GDI technology is the increase in particulate emissions compared to the commonly used port fuel injection technologies. Today’s adopted strategy to limit such emissions relies upon the use of aftertreatment gasoline particulate filters (GPFs). GPFs reduce particulates resulting from fuel combustion. Soot oxidation (also known as regeneration) is required at regular intervals to clean the filter, maintain a consistent soot trapping efficiency, and avoid the formation of soot plugs in the GPF channels. In this paper, starting from a multiphysics GPF model accounting for mass, momentum, and energy transport, a sensitivity analysis is carried out to choose the best mesh refinement, time step, and relative tolerance to ensure a stable numerical solution of the transport equations during regeneration while maintaining low computational time.

For the NOx removal from diesel exhaust, the selective catalytic reduction (SCR) and lean NOx traps are established technologies. However, these procedures lack efficiency below 200 °C, which is of importance for city driving and cold start phases. Thus, the present paper deals with the development of a novel low-temperature deNOx strategy implying the catalytic NOx reduction by hydrogen. For the investigations, a highly active H2-deNOx catalyst, originally engineered for lean H2 combustion engines, was employed. This Pt-based catalyst reached peak NOx conversion of 95 % in synthetic diesel exhaust with N2 selectivities up to 80 %. Additionally, driving cycle tests on a diesel engine test bench were also performed to evaluate the H2-deNOx performance under practical conditions. For this purpose, a diesel oxidation catalyst, a diesel particulate filter and a H2 injection nozzle with mixing unit were placed upstream to the full size H2-deNOx catalyst.

A physics-based model for SCR (Selective Catalytic Reduction) was developed based on five independent SGB (Synthetic Gas Bench) tests. There are NH3 adsorption & desorption test, NO oxidation test, NH3 oxidation test, SCR reaction (NOx & NH3) test and SV (Space Velocity) test. To validate the accuracy of SCR model’s prediction, transient reactor tests were conducted at four different input conditions. A newly developed SCR model showed more than 90% prediction accuracy in transient test conditions in view of cumulative NOx. Validation of SCR model was conducted on 1.6L light duty diesel vehicle in the WLTC (Worldwide Harmonized Light vehicles Test Cycle). Based upon this SCR model, vehicle level SCR calibrations used for urea dosing control were made and validated in the emission test cycles like WLTC.

Selective Catalytic Reduction (SCR) is a process where one injects an aqueous solution of urea into a diesel exhaust system in order to reduce NOx emissions. The urea solution known as AdBlue® or Diesel Exhaust Fluid (DEF) is stored in a DEF Tank that can under cold weather conditions freeze over. Since AdBlue® is unusable while frozen, we use heaters installed in the tanks to melt AdBlue® with government regulations mandating time required to melt AdBlue® in the tank. In this article, we investigate whether a CFD (Computational Fluid Dynamics) based methodology can accurately evaluate time required in melting AdBlue® for a given DEF Tank and heater coil design for a production vehicle as per standard testing procedure. Simulations used a coupled methodology with PowerFLOW® as the flow solver and PowerTHERM® as the thermal solver. The flow simulation did require an accurate modelling of phase change from solid to liquid for AdBlue®.

To fulfill stringent emission legislation requirements, it is essential to understand the relation between aging processes of the exhaust gas aftertreatment system (ATS) and its performance. The Stage V compliant heavy-duty non-road aftertreatment system, which was used in this study, is comprised of a diesel oxidation catalyst (DOC) placed directly after the engine, followed by a particulate filter with a selective catalytic reduction (SCR) active coating (SCRoF) and is completed by an SCR-coated substrate combined with an NH3 oxidation catalyst. Each of the ATS components has to work in synergy and interact with each other to fulfill the emission legislation requirements. During vehicle operation, the ATS is exposed to various chemical and physical factors, which deteriorate its performance over its lifetime. In this work, the accelerated aging methodology is presented.

The diesel engine is the core in the field of engineering machine power plants. While both at home and abroad for the cold start of diesel engine, the transient emission characteristics below 0 °C and above 2000m is almost a blank. Therefore, aimed at high altitude and low-temperature environment emission characteristics of cold start, this article has carried on the systematic analysis and research. In this paper, a simulation test system for the cold start of the diesel engine at low temperature at high altitude is established. The cold start experiments of a heavy diesel engine at different ambient temperatures (10°C, 0°C, -10°C and -20°C) and different altitudes (0m, 3000m, and 4000m) is carried out. In this paper, the gas emission of the diesel engine during the speed-up period of cold start is studied.

Future legislations such as EPA27 [1] and EURO VII [2] are further reducing NOx emission limits. At the same time, the focus of emission compliance over a broad range of operation conditions is becoming more stringent; with a specific focus onto the cold start. The reduction of NOx is reached over a Selective Catalytic Reduction (SCR) system, with NH3 as a reductant. NH3 is derived over the processing of Urea Water Solution (UWS) to NH3. The conversion of UWS to NH3 is a highly complex process, with the danger of deposit formation, which is especially challenging in Compact Urea Processing Units (CUPU). One of the key factors for the successful development of Compact Urea Processing Units is the precise application of simulation and testing methods. Therefore, existing testing methods e.g. for the determination of the urea processing capability or the deposit formation were optimized, new testing methods are being introduced and the parameters evaluated are being broadened.

In addition to the low and high beam functions, some modern headlamps also have the option of switching on only section of the high beam. The so-called adaptive high beam is intended to increase the detection distance of objects and through that drastically improve the road safety. At the same time, this function does not increase the glare for oncoming or preceding traffic. This is enabled through switching the different segments of the high beam on or off, depending on which and where other road users are recognized by the front camera. This massively increases the use of the high beam, thus increasing road safety. In this study, the increase in the detection distance of objects on a straight line is statically investigated with a test person study. Furthermore, the glare of each of these three light functions is observed.

In order to reduce the carbon footprint of the Internal Combustion Engine (ICE), biofuels have been in use for a number of years. One of the problems with first-generation (1G) biofuels however is their competition with food production. In search of second-generation (2G) biofuels, that are not in competition with food agriculture, a novel biorefinery process has been developed to produce biofuel from woody biomass sources. This novel technique, part of the Belgian federal government funded Ad-Libio project, uses a catalytic process that operates at low temperature and is able to convert 2G feedstock into a stable light naphtha. The bulk of the yield consists out of hydrocarbons containing five to six carbon atoms, along with a fraction of oxygenates and aromatics. The oxygen content and the aromaticity of the hydrocarbons can be varied, both of which have a significant influence on the fuel’s combustion and emission characteristics when used in Internal Combustion Engines.

Over the last decades, electric vehicles (EVs) have emerged as an alternative to internal combustion engine vehicles. EVs have different propulsion and fuel intake system when compared to internal combustion engine vehicles. Therefore, cradle-to-gate (CTG) and well-to-wheel (WTW) greenhouse gas emissions (GHGs) would be different. In this study, life cycle GHG emissions of vehicle cycle and fuel cycle are compared between EV and internal combustion engine (ICEV) powered by petrol and diesel as fuel. This study used the average curb weight of all three types of vehicles based on the availability and popularity in the Indian market (as a case study) for life cycle assessment. The Greenhouse Gases, Regulated Emissions, and Energy use in Transport (GREET) model developed by Argonne National Laboratory was adopted to conduct the life cycle assessment. The mileage of 150,000 km over the whole life period was assumed for all types of vehicles.

As the number of electric vehicles (EVs) within society rapidly increase, the concept of maximizing its efficiency within the electric smart grid becomes crucial. This research presents the impacts of integrating EV charging infrastructures within a smart grid through a vehicle to grid (V2G) program. It also observes the circulation of electric charge within the system so that the electric grid does not become exhausted during peak hours. This paper will cover several different case studies and will analyze the best and worst scenarios for the power losses and voltage profiles in the power distribution system. Specifically, we seek to find the optimal location as well as the ideal number of EVs in the distribution system while minimizing its power losses and optimizing its voltage profile. Verification of the results are primarily conducted using GUIs created on MATLAB.

As the automated vehicle (AV) industry continues to progress, it is important to establish the level of operational safety of these vehicles prior to and throughout their deployment on public roads. The Institute of Automated Mobility (IAM) has previously proposed a set of operational safety assessment (OSA) metrics which can be used to quantify the operational safety of vehicles. The OSA metrics provide a starting point to consistently quantify performance, but a framework to interpret the metrics measurements is needed to objectively quantify the overall operational safety for a vehicle in a given scenario. This work aims to present an approach to applying a calculation of the safety envelope component of the OSA metrics to rear-world collisions for use in such an assessment. In this paper, the OSA methodology concept is introduced as a means for quantifying the operational safety of a vehicle.

Autonomous Driving is the next big thing in the Automotive future. With growing automation, there is also growing need for In-cabin and Occupant monitoring. Impaired driving as a cause constitute a statistically major portion of the total accidents in the world. Additionally, the aging society of road users add to health concerns of possible drivers behind the wheel which might lead to severe accidents. Since the accident and the associated damage would have been occurred due to incapacitated drivers in the first place, there arises a need to know the state of drivers while driving to ensure the safety of him and other road users. Therefore, the monitoring of the driver's state and detection of any deviation from the suitable driving condition is significant to reduce the number of accidents on the road. One of the efficient ways to know the drivers’ state is to monitor the health - physical, mental and emotional, of the drivers essentially.

In this paper we present a project that interfaced the National Advanced Driving Simulator (NADS) with SynChrono, a module of the Project Chrono open source simulation platform, to enable real-time, physics-based simulation of multiple autonomous vehicles (AVs) interacting with manned vehicles. In this setup, a driver at NADS, at the University of Iowa, participates in a traffic scenario that involves AVs that run at the University of Wisconsin-Madison on a cluster supercomputer. The NADS simulator is a driving simulator giving the “most realistic driving simulation experience in the country” [1]. Thanks to its actuators, it can move across its 64-foot by 64-foot bay, rotate and tilt, to emulate vehicle movement and vibrations. In addition, the human driver drives in a full-size cab, surrounded by LED monitors, resulting in an immersive, high fidelity driving simulation experience.

Rising electric scooter popularity has seen a surge in electric scooter crashes. Crash reconstructionists increasingly have access to global positioning system (GPS) data for micromobile vehicle trips, and GPS devices can produce a wealth of data about cyclists’, scooterists’, and other riders’ road paths and route usage. However, prior research has demonstrated that GPS positional accuracy is less reliable for more nuanced roadway positioning, such as which lane a vehicle occupies, as well as within-lane movements, such as acceleration and deceleration⁠. This limitation presents a challenge for crash reconstructionists that may have access to GPS data and require second-by-second positional accuracy to determine such nuanced maneuvers and vehicle positioning in their analysis. The purpose of this study was to explore the positional accuracy of five GPS units for a micromobile vehicle during three different ride conditions: acceleration, deceleration, and constant speed.

The glare to pedestrians remains one of the biggest challenges since the invention of the automobile and the automobile lighting. As far as pedestrians are concerned, whether the roadside pedestrians or the pedestrians in the crossing area are almost like lambs to the slaughter. To balance the glare interference of automobile lighting and protecting pedestrians, modeling and simulation for the pedestrian glare have been theorized by the use of forest sunlight effects and a novel controlled dark photonic channel. Based on the modeling and simulation, a novel full-factors light environment control system and pedestrian glare-free lighting system have been derived.