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With the increasing focus on reducing CO2 emissions to combat global warming and climate change, the automotive industry is exploring near zero-emission alternative fuels to replace traditional fossil-based fuels like diesel, gasoline, and CNG. Methanol is a promising alternative fuel that is being evaluated in India due to its easy transportation and storage, as well as its production scalability and availability potential. This study focuses on the retro-fitment solution of M100 (pure methanol) SI port-fuel injection (PFI) mode of combustion. A heavy duty single-cylinder engine test setup was used to assess methanol SI combustion characteristic. Lean operation strategy has been investigated. At lean mixture conditions a significant drop in NOX and CO emissions was achieved. The fuel injection techniques and the impact of exhaust gas recirculation (EGR) on the conventional stoichiometric combustion process is highlighted.

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.

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.

The proposed Euro 7 emission standard foresees that the emission behaviour of Euro 7 vehicles is monitored via an on-board monitoring (OBM) system. In Euro 7 vehicles, OBM systems will monitor the emissions of nitrogen oxides (NOX), ammonia (NH3) and particulate matter (PM) for every trip through a combination of measured and modelled data. Sensors employed to support on-board diagnostics (OBD) in current vehicles may be used to support OBM. According to the Euro 7 OBM concept presented in this paper, OBM will serve a dual purpose: the first is to warn the user of a vehicle about the need to perform repairs on the engine or the pollution control systems when these are needed. If these repairs are not performed in a timely manner, the OBM system will be able to ultimately prevent engine restart, akin to the existing low-reagent driver warning system in some compression ignition vehicles. The second purpose of OBM is to monitor the compliance of vehicle types with the emission limits.

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.

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.

Heavy-duty vehicles represent a significant portion of road transport and they need to operate in a clean and efficient manner. Their emission control systems need to be enhanced to sustain the high conversion efficiencies seen during motorway conditions inother operating conditions. The European Commission is developing legislative proposals for Euro 7 emissions regulations for light- and heavy-duty vehicles. The new Euro 7regulation will likely focus on ensuring the emissions from heavy-duty vehicles are minimized over extensive on-road operating conditions and specifically on operating conditions such as urban driving and cold-start operation. These challenges are increased by the need to ensure low secondary emissions like NH3 and N2O, as well as a low impact on CO2 emissions. The paper outlines the low pollutant emissions achieved by a heavy-duty Diesel demonstrator vehicle.

This paper focusses on the supply conditions of a connecting rod bearing. Thereto, a novel simulation approach is presented, which is based on a transient 3D-CFD multiphase flow simulation including the ability of gas dissolution and diffusive mass transfer. The model determines the pressure behavior and the gas bubble development in the oil supply system of a connecting rod bearing. It allows to visualize the flow behavior and the existence of gas bubbles in order to get a detailed impression of the physical occurrences. The experimental results from Maaßen [5], where a big gas bubble is formed in the supply bore by gas cavitation, are confirmed and used for validation. Further the flow behavior of free air ratios is investigated. The paper concludes that the supply conditions of a connecting rod bearing are strongly influenced by the gas bubble in terms of the fluid composition and the volume flow rate at the connecting rod bearing inlet.

Catalyst fouling by deposit formation on components in the exhaust aftertreatment system is critical since RDE limits must be obtained at any time. Besides, uncontrolled oxidation of carbonaceous deposits might damage the affected exhaust aftertreatment component. To comply with current and future emission standards, diesel engines are usually operated with high EGR rates leading to increased soot and hydrocarbon emissions, which increases the likeliness of the formation of carbonaceous deposits on EAT components. With this background, a research project investigating the influencing parameters and mechanisms of deposit formation on DOCs was carried out. In a follow-up project, the results will be used in order to compare different deposit removal strategies. Within the scope of the presented project, a reference driving cycle was developed in order to create deposits within a short time.

Exhaust aftertreatment systems must function sufficiently over the full useful life of a vehicle. In Europe this is currently defined as 160.000 km. With the introduction of Euro 7 it is expected that the required mileage will be extended to 240.000 km. This will then be consistent with the US legislation. In order to quantify the emission impact of exhaust system degradation, an Euro 7 exhaust aftertreatment system is aged by different accelerated approaches: application of the Standard Bench Cycle, the ZDAKW cycle, a novel ash loading method and borderline aging. The results depict the impact of oil ash on the oxygen storage capacity. For tailpipe emissions, the maximum peak temperatures are the dominant aging factor. The cold start performance is effected by both, thermal degradation and ash accumulation. An evaluation of this emission increase requires appropriate benchmarks.

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.

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.

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.

Super ultra-low NOX emission engine concepts are essential to comply with future emission legislations. To meet the future emission standards, application of advanced diesel exhaust aftertreatment systems (EATS), such as Diesel Oxidation Catalyst (DOC), Lean NOX Trap (LNT), Selective Catalytic Reduction coatings on Soot Filters (SCRF) and underfloor SCR, is required. Effective customized thermal management strategies are essential to ensure fast light-off of the EATS after engine cold start, and to avoid significant cooldown during part load operation. The authors describes the investigation of different exhaust gas heating measures, such as intake throttling, late fuel injection, exhaust throttling, advanced exhaust cam phasing, retarded intake cam phasing, cylinder deactivation, full turbine bypass, electric catalyst heating and electrically heated intake manifold strategies.

Advanced powertrains for modern vehicles require the optimization of conventional combustion engines in combination with tailored electrification and vehicle connectivity strategies. The resulting systems and their control devices feature many degrees of freedom with a large number of available adjustment parameters. This obviously presents major challenges to the development of the corresponding powertrain control logics. Hence, the identification of an optimal system calibration is a non-trivial task. To address this situation, physics-based control approaches are evolving and successively replacing conventional map-based control strategies in order to handle more complex powertrain topologies. Physics-based control approaches enable a significant reduction in calibration effort, and also improve the control robustness.

In order to reduce pollutant and CO2 emissions and fulfill future legislative requirements, powertrain electrification is one of the key technologies. In this context, especially 48V technologies offer an attractive cost to CO2 reduction ratio. 48V mild hybrid powertrains greatly benefit from additional electric intake air compression (E-Charging) and direct torque assist by an electric machine (E-Boosting). Both systems significantly improve the transient engine behavior while reducing the low end torque drawbacks of extreme downsizing and downspeeding. Since E-Charging and E-Boosting have different characteristics concerning transient torque response and energy efficiency, application of model predictive control (MPC) is a particularly suitable method to improve the operating strategy of these functions. MPC requires fast running real-time capable models that are challenging to develop for systems with pronounced nonlinearities.

This article discusses highly flexible and accurate physics-based mean value modeling (MVM) for internal combustion engines and its wide applicability towards virtual vehicle calibration. The requirement to fulfill the challenging Real Driving Emissions (RDE) standards has significantly increased the demand for precise engine models, especially models regarding pollutant emissions and fuel economy. This has led to a large increase in effort required for precise engine modeling and robust model calibration. Two best-practice engine modeling approaches will be introduced here to satisfy these requirements. These are the exclusive MVM approach, and a combination of MVM and a Design of Experiments (DOE) model for heterogeneous multi-domain engine systems.

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.

Upcoming China 4th stage of fuel consumption regulation and China 6a emission legislation require improvement of many existing engines. This paper summarizes an upgrade of combustion system and mechanical layout for a four-cylinder engine family. Based on an existing production process for a naturally aspirated 2.0-liter gasoline engine, a 1.8-liter down-speeded and turbocharged gasoline engine is derived. Starting development by analysis of engine base geometry, a layout for a Miller-Cycle gas exchange with early closing of intake valves is chosen. Requirements on turbocharger configuration are investigated with one-dimensional gas exchange simulation and combustion process will be analyzed by means of 3D-CFD simulation. Challenging boundary conditions of a very moderate long-stroke layout with a stroke/bore-ratio of only 1.037 in combination with a cost efficient port fuel injection system and fixed valve lift profiles are considered.

The use of state-of-the-art model-based calibration tools generate only limited benefits for seamless validation in powertrain calibration due to the often neglected system-level simulation of a closed-loop vehicle environment. This study presents a Hardware-in-the-Loop (HiL)-based virtual calibration approach to establish an accurate virtual calibration platform using physical plant models. It is based on a customisable real-time HiL simulation environment. The use of physical models to predict the behaviour of a complete powertrain makes the HiL test bench particularly suited for Engine Control Unit (ECU) calibration. With the virtual test rig approach, the calibration for the critical extended driving and ambient conditions of the new Real Driving Emissions (RDE) requirements can efficiently be optimised. This technique offers a clear advantage in terms of reducing calibration time and costs.