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The implementation of emission standards has brought significant reductions in vehicle emissions in the EU, but road transport is still a major source of air pollution. Future emission standards will aim at making road vehicles as clean as possible under a wide range of driving conditions and throughout their complete lifetime. The current paper presents the methodology followed by the Consortium for ultra LOw Vehicle Emissions (CLOVE) to support the preparation of the Euro 7 proposal. As a first step, the emission performance of the latest-technology vehicles under various driving conditions was evaluated. Towards this direction, an emissions database was developed, containing data from a wide range of tests, both within and beyond the current RDE boundaries.

The automotive industry continues to develop new powertrain and vehicle technologies aimed at reducing overall vehicle-level fuel consumption. Specifically, the use of innovative drivetrain technologies including conventional and electrified propulsion systems is expected to play an increasingly important role in helping OEMs meet fleet CO2 reduction targets for 2025 and beyond. NVH development for vehicles with electrified powertrains introduces new challenges, which need to be understood and solved. The electrified vehicle space spans variants from micro and mild hybrids all the way through plug-in hybrids and fully electric vehicles. In addition to conventional NVH development methodologies, active sound design (ASD) can play a crucial role to enhance the interior sound perception of such vehicles and hence, improve customer acceptance of new technologies. This paper will begin with an introduction to the NVH challenges posed by electrified vehicles.

Climate change and global warming are one of the major challenges faced by the world today. A significant number of Indian cities rank among the most polluted globally, with vehicular emissions being the primary contributor. To address this issue, the Government of India is actively advocating for the adoption of zero-emission vehicles such as electric vehicles through policies and initiatives like FAME II [1], PMP and the National Mission for Transformative Mobility and Storage. The acceptance of electric vehicles is growing in the Indian market seeing more than 200% increase in sales in the year 2022 compared to 2021 with a large share of 2-wheelers, 3-wheelers and compact cars getting electrified. Further adoption of electrification on a much larger scale currently faces the major challenge of high overall vehicle cost compared to conventional vehicles, with the major contribution coming from the HV battery which is the costliest system on the electric vehicles.

Governing bodies world-wide are setting increasingly tighter emission standards to help improve air quality. US and Californian LEV/ULEV standards are pace setting, European Stage II legislation has just become effective. In Brazil, the upcoming 1997 standards are also demanding for tighter emission control. The monolithic ceramic honeycomb catalytic converter -for more than the past 20 years- has been a reliable key element in the automotive emission control systems. In order to help meet tightened emission regulation as well to satisfy even more stringent durability requirement, an advanced thinwall ceramic Celcor XT has been developed for increased geometric surface area and reduced backpressure. The product properties as well as FTP and ECE emission and durability test results are being described in this paper. Converter system durability is also determined by robust canning and mounting systems. A durable mounting concept, especially for preconverters, is being described.

The trend to simultaneously improve fuel economy and engine performance has led to industry growth of turbocharged engines and as a result, the need to address their undesirable airborne noise attributes. This presents some unique engineering challenges as higher customer expectations for Noise Vibration Harshness (NVH), and other vehicle-level attributes increase over time. Turbocharged engines possess higher frequency noise content compared to naturally aspirated engines. Therefore, as an outcome, whoosh noise in the Air Induction System (AIS) during tip in conditions is an undesirable attribute that requires high frequency attenuation enablers. The traditional method for attenuation of this type of noise has been to use resonators which adds cost, weight and requires packaging space that is often at a premium in the under-hood environment.

Most of the vehicles with internal combustion engines worldwide use fossil fuels. The widely used fuels available on the market are gasoline, diesel, and CNG. These fuels are getting costlier every year while at the same time generating pollutants through exhaust gases. Hence in the market, electric vehicles are effectively providing pollution-free solutions in the passenger car and lightweight carrier vehicle segments. However, the off-road, heavy-duty, and stationary applications with high load factors, are in general less favorable for battery electric scenarios since frequent charging will be mandatory and time-consuming. Hence, for these applications, the replacement of an internal combustion engine is quite difficult. There are various renewable fuels like ammonia, methanol, and biodiesel under research tests and study. As these are renewable fuels, the cost of these fuels can be lowered during mass production.

Gasoline particulate filters (GPF) recently entered the market, and are already regarded a state-of-the-art solution for gasoline exhaust aftertreatment systems to enable EU6d-TEMP fulfilment and beyond. Especially for coated GPF applications, the prognosis of the emission conversion performance over lifetime poses an ambitious challenge, which significantly influences future catalyst diagnosis calibrations. The paper presents key-findings for the different GPF application variants. In the first part, experimental GPF ash loading results are presented. Ash accumulates as thin wall layers and short plugs, but does not penetrate into the wall. However, it suppresses deep bed filtration of soot, initially decreasing the soot-loaded backpressure. For the emission calibration, the non-linear backpressure development complicates the soot load monitoring, eventually leading to compromises between high safety against soot overloading and a low number of active regenerations.

The Bharat Stage (CEV/Tractor) IV & V emission legislations will come into force in Oct 2020 & Apr 2024 respectively, posing a major engineering challenge in terms of system complexity, reliability, costs and development time. Solutions for the EU Stage-V NRMM legislation in Europe, from which the BS-V limits are derived, have been developed and are ready for implementation. To a certain extent these European solutions can be transferred to the Indian market. However, certain market-specific challenges are yet to be defined and addressed. In addition, a challenging timeline has to be considered for application of advanced technologies and processes during the product development. In this presentation, the emission roadmap will be introduced in the beginning, followed by a discussion of potential technology solutions on the engine itself as well as on the after treatment components.

The fuel consumption of combustion engines requires continuous reduction to meet future CO2 fleet targets. The progression of emission legislations shifted the focus on PN and NOX emissions in real world driving scenarios (RDE). Recently, the monitoring of CO emissions puts high load fuel enrichment for component protection into focus and a ban on enrichment is widely expected. Hence, gasoline engine technologies, which enable Lambda 1 operation in the entire engine map are specifically promoted. Variable Compression Ratio (VCR) attacks all these topics already at the combustion process. In addition to the well-known CO2 capability, VCR also enables enlargement of the lambda 1 operation in gasoline engines as well as reduced NOX emissions in diesel engines. The basic principle of developed VCR solution is to change the effective length of the connecting rod (and thereby the compression ratio) in two stages by several millimeters.

Virtual system integration and testing using hardware-in-the-loop (HiL) simulation enables front-loading of development tasks, provides a safer and reliable testing environment and reduces prototype hardware costs. One of the greatest challenges to overcome when performing HiL simulations is assuring a high model accuracy under stringent real-time requirements with acceptable development effort. This article represents a novel solution by deriving the plant model for HiL directly from the existing detailed models from the component layout phase using co-simulation methodology. It provides an effective and efficient model implementation and validation process followed by detailed quantitative analysis of the test results referred to the engine test bench measurements.

Catalytic converter substrates for automobile emission control have to operate under the hostile conditions of the automotive exhaust. This paper will first discuss the mechanical and physical properties to ensure durable mechanical function of the catalytic substrate and converter system. High temperature mechanical and thermal shock substrate requirements and properties will be discussed. The functionality of a catalytic converter is significantly influenced by the catalytic coating. At the same time, substrate characteristics as will be shown, also effect converter functional parameters like back pressure, light-off and conversion efficiency. The importance of the substrate parameters cell shape, cell density and substrate mass and their effect on thermohydraulic parameters like heat- and mass transfer factors for various cell structures and substrates will be presented.

Upcoming EU5 and expected emissions legislation BS5 in India in combination with efforts to optimize the overall fuel economy has created new challenges in the development of aftertreatment systems for passenger cars equipped with diesel engines. Since EU5 and BS5 emissions legislation will strongly be focused on the reduction of particulate matter it is likely that all vehicle applications will need aftertreatment systems with diesel particulate filters. High filtration efficiency combined with a high resistance to thermo-mechanical stress is a strong requirement for diesel particulate filters to meet EU5 and BS5 emission legislation. Besides those requirements the backpressure of particulate filters has to be considered since backpressure is also related to fuel economy and therefore CO₂ emissions.

From April 2020 BS 6 phase 1 legislation has come into place in India. Further in the coming years from 2022 CAFÉ norms will be implemented targeting 122 g/km CO2 fleet emissions. Also, from year 2023 onwards BS 6 phase 2 emission legislation with RDE cycle will be in place. With the expensive exhaust after-treatment system needed for meeting BS 6 norms, the Diesel powertrain based vehicles cost has increased further creating even further price difference to it’s Gasoline fuel variants. Additionally, the price difference between Diesel and Gasoline fuel is always reducing. These reasons have changed the buying pattern of passenger cars in India, with vehicle powered by engine<1.5 L displacements have gradually shifted predominantly to Gasoline powertrain. The impact of this will further stress the fleet CO2 emissions for manufacturers.

Modeling thermal systems in Battery Electric Vehicles (BEVs) is crucial for enhancing energy efficiency through predictive control strategies, thereby extending vehicle range. A major obstacle in this modeling is the often limited availability of detailed system information. This research introduces a methodology using neural networks for system identification, a powerful technique capable of approximating the physical behavior of thermal systems with minimal data requirements. By employing black-box models, this approach supports the creation of optimization-based operational strategies, such as Model Predictive Control (MPC) and Reinforcement Learning-based Control (RL). The system identification process is executed using MATLAB Simulink, with virtual training data produced by validated Simulink models to establish the method's feasibility. The neural networks utilized for system identification are implemented in MATLAB code.

Gasoline engine powertrain development for 2025 and beyond is focusing on finding cost optimal solutions by balancing electrification and combustion engine efficiency measures. Besides Miller cycle application, cooled exhaust gas recirculation and variable compression ratio, the injection of water has recently gained increased attention as a promising technology for significant CO2 reduction. This paper gives deep insight into the fuel consumption reduction potential of direct water injection. Single cylinder investigations were performed in order to investigate the influence of water injection in the entire engine map. In addition, different engine configurations were tested to evaluate the influence of the altering compression ratios and Miller timings on the fuel consumption reduction potential with water injection.

The increasing complexity of modern combustion engines together with the substantial variability of hybrid electric powertrains, lead to new challenges in function development, system integration and vehicle calibration processes. Hardware-in-the-Loop (HiL) simulations have been introduced to front-load part of the testing and calibration tasks from the vehicle to a virtual environment. With this approach, the simulation quality and the cost-benefit ratio are strongly dependent on the accuracy of the plant modelling and the computational effort. This paper introduces a novel HiL simulation platform for an engine control unit (ECU) with a crank-angle resolved real-time model (GT-Power) for a gasoline engine with direct fuel injection, single stage turbocharging and a three-way catalyst. By simplifying the fluid dynamics simulation model from the concept phase, a good compromise between model accuracy and computation speed can be achieved with relatively low effort.

Indian cities are among the most polluted in the world. The transportation sector is one of the major sources of gaseous pollutants. In recent years, also the effects of climate change and global warming have been felt across the globe. India has therefore committed at the CoP26 summit in 2021 to reduce its CO2 emissions by 45% till the year 2030. The Indian automotive sector is already addressing the problem with implementation of the Stage 2 BS VI norms, CAFÉ & Stage V standards and pursuing rapid electrification with application of zero emission vehicles. India also has the largest rail network of Asia, and a significant proportion of greenhouse gases is emitted by this sector. Deployment of zero emission fuel cell trains would be one of the solutions to meet India’s emission reduction targets.

In this article, the development challenges of a fuel cell system are explained using the example of the BREEZE! fuel cell range extender (FC-REX) applied in an FEV Liiona. The FEV Liiona is a battery electric vehicle based on a Fiat 500 developed by FEV. The BREEZE! system is the first applied 30 kW low temperature polymer electrolyte membrane (LT PEM) fuel cell system in the subcompact vehicle class. Due to the highly integrated system approach and dry cathode operation, a compact design of the range extender module with a system power density of 0.45 kW/l can be achieved so that the vehicle interior including trunk remains completely usable. System development for fuel cells significantly influences performance, efficiency, package, durability, and required maintenance effort of a fuel cell electric powertrain. In order to ensure safe and reliable operation, the fuel cell system has to be supplied with sufficient amounts of air, hydrogen, and coolant flows.

Our expectations in lubrication systems applied in modern powertrains are continually rising. Beginning with the basic function of cooling and lubricating tribological contacts such as cylinder liner and piston, bearings, gears, chain drives and various valve train contacts, the oil in the lubrication system is now increasingly being used as a hydraulic fluid. Examples are (fully) variable valve trains, variable compression ratio systems or complicated transmission hydraulics. Driven by the general trend to minimize mechanical losses in order to increase the overall powertrain efficiency, the introduction of variable capacity oil pumps is commonly seen in latest engine designs. The potential to decrease oil pressure levels and volumetric oil flow in order to minimize mechanical losses on the one hand significantly complicates the reliable fulfillment of the aforementioned tasks of the lube systems on the other hand.

In the field of gasoline powertrain calibration, the challenges are growing due to ever shorter time-to-market requirements and a simultaneous increase in powertrain complexity. In addition, the great variety of vehicle variants requires an increasing number of prototypes for calibration and validation tasks within the framework of the current Real Driving Emissions (RDE) regulations and the expected Post Euro 6 emission standards. Hardware-in-the-Loop (HiL) simulations have been introduced successfully to support the calibration tasks in parallel to the conventional vehicle development activities. The HiL approach enables a more reliable compliance with emission limits and improves the quality of calibrations, while reducing the number of prototype vehicles, test resources and thus overall development costs.