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The automotive trend is now days switching towards less weight, cost effective and power efficient powertrain. Consumer’s expectations from comfort and NVH point of view is rising day by day. The NVH performance of a powertrain is mainly affected by the powertrain mounting System. In design and development of a new vehicle, the mounting of the powertrain (engine-transmission assembly) receives special attention. The powertrain body is the major concentrated mass in the vehicle Which if not adequately confined and quarantined, it will result in poor NVH characteristics of powertrain. In this work a powertrain mounting System of three-cylinder engine, which is transversely mounted, is analyzed. A correlation between two different simulation techniques has been established. Passive mounts are being assessed throughout the investigation. A multi body simulation approach is employed for the modelling and simulation of powertrain mounting system.

The prime target of IEA (international energy association) to reduce global average emission by 50% in 2030 has prompted focused R&D on automotive emission reduction as well as NEV (new energy vehicles). Of these strategies, engine downsizing constitutes the group of strategies employed to meet lower emission and fuel consumption targets in IC engines. Downsizing strategies have been proved successful in reducing emissions. There is widespread trend of downsizing existing engines with a goal to produce lower emissions along with equal or better performance. To achieve the stated goals downsized engines are usually charged or employ higher compression ratios. This raises NVH as well as structural issues that need further analysis. While the concept of downsizing has been studied in deep, its structural effects and NVH related issues are of concern. This paper throws light into different engine downsizing strategies and their effect on NVH.

One of the most promising fuel alternatives for Diesel is Methanol. The fuel is regarded advantageous owing to the easy availability of raw materials for its production, its low cost and high Oxygen content that has potential to reduce emissions of smoke, CO and PM. Methanol as a fuel blend with Diesel is non-viable as they are not readily miscible with each other. This paper expounds the engine performance and emission evaluation of blending Methanol with Diesel by using two methods that aid in overcoming phase separation. The experiments were performed in two stages. In the first stage, investigation of phase stabilization of Methanol in Diesel with suitable additive concentration was performed. This was performed to determine the optimum additive and its concentration for a Methanol share of up to 25% in Diesel-Methanol blends for a stabilization period of 30 days.

Climate change is a global phenomenon now and countries across the globe are working towards reducing emissions by bringing in stricter legislations on emissions and CO2. India is also facing huge challenges on pollutions in large cities. Reports suggest that 7 of the 10 most polluted cities of the world lie in India. The growing public opinion towards cleaner air and reduced greenhouse gaseous emissions has sensitized the matter and has led to drafting of strict emission legislations in India during the past few years. The leap frogging from BS 4 to BS 6 in 2020 by skipping BS 5 norms showed the intent of the GOI towards emission reduction. The BS 6 legislation is not limiting to meeting norms with legislative emission cycle but will also focus from year 2023 onto real driving emissions on actual roads. GOI is also proposing to implement fleet CO2 emission norms (CAFÉ) by 2022 to regulate the CO2 emissions.

The ever-increasing cost of automotive powertrain development is due to the more complex technologies required to meet the latest emissions legislation and customer expectations. Manufacturers need to conduct extensive development loops of test bench and on-road testing to verify the hardware, emission control system, corresponding ECU software function development. Increased resources are required to build up a comparably large number of prototype vehicles to calibrate all the ECU algorithms and functionalities. Increasing powertrain complexity leads typically to a strong increase of conventional calibration efforts. Therefore, there is a strongly increasing need for an advanced calibration approach based on multi-facial XiL simulation.

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 combustion of transportation fuels remains a difficult task due to the extremely large number of species constituting commercial gasoline and diesel. However, for this purpose, multi-component surrogate fuel models with a reduced number of key species and dedicated reaction subsets can be used to reproduce the physical and chemical traits of diesel and gasoline, also allowing to perform CFD calculations. Recently, a detailed surrogate fuel kinetic model, named C3 mechanism, was developed by merging high-fidelity sub-mechanisms from different research groups, i.e. C0-C4 chemistry (NUI Galway), linear C6-C7 and iso-octane chemistry (Lawrence Livermore National Laboratory), and monocyclic aromatic hydrocarbons (MAHs) and polycyclic aromatic hydrocarbons (PAHs) (ITV-RWTH Aachen and CRECK modelling Lab-Politecnico di Milano).

Vehicles are one of the main sources of pollution in India, which produce substantial amount of pollutants. Gaseous pollutants are reason for major health problems; hence emission legislations are becoming increasingly stringent all over the world. India is also following the global trend of migrating in the Off-highway segment from Trem IIIA to Stage V legislation by 2024. This legislation change is calling for technological upgrade of all existing engines. EGR has been successfully proved as a useful technology to reduce NOx by decreasing the oxygen concentration and the peak temperature of the combustion. Due to compact design and space restriction, the distance required for the homogeneous mixing of fresh air and EGR is not enough. Therefore, the mixing of the EGR and distribution of the EGR over the cylinders may not be equal.

Legislations on vehicular noise levels are becoming stringent day by day. Also the customer expectations on the vehicle noise levels has also become more refined in the India market. Intake and exhaust flow noise levels are one of the major contributors to this overall noise level of the vehicle. These drivers have led the Indian automobile manufacturers to focus on engine and vehicle noise optimization. The 3-wheeler and 4-wheeler Quadra-cycle vehicles which are powered by single cylinder engines are more prone to high noise levels due to pulsating intake and exhaust flow dynamics caused by single firing cylinder. The study focuses on the exhaust muffler design optimization of a single cylinder engine powertrain to meet the targeted noise levels. One - Dimensional (1D) Simulation tools give significant information at the system level and reduce the time required for analysis and optimization compared to the three - dimensional (3D) CFD tools.

The Computational Chemistry Consortium (C3) is dedicated to leading the advancement of combustion and emissions modeling. The C3 cluster combines the expertise of different groups involved in combustion research aiming to refine existing chemistry models and to develop more efficient tools for the generation of surrogate and multi-fuel mechanisms, and suitable mechanisms for CFD applications. In addition to the development of more accurate kinetic models for different components of interest in real fuel surrogates and for pollutants formation (NOx, PAH, soot), the core activity of C3 is to develop a tool capable of merging high-fidelity kinetics from different partners, resulting in a high-fidelity model for a specific application. A core mechanism forms the basis of a gasoline surrogate model containing larger components including n-heptane, iso-octane, n-dodecane, toluene and other larger hydrocarbons.

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.

This paper presents the FEV low cost EV platform intended to provide a modular and scalable platform for 2 and 3 wheelers that is robust and meets the desired performance characteristics. To enable this, we use a dedicated vehicle control unit (VCU) that is running FEV’s matured model library called PERSIST. The platform makes use of the inherent advantage of being a small scale vehicle that can be used with lower sized components or reduced set of components without compromising on safety. The electric vehicle platform will have modularly developed components and associated software and hardware with standardized interfaces. The electric power train includes support for standardized lithium ion batteries and a low cost vehicle control unit. This is required to not only safe guard the system overall but also be able to optimize the driving range, enhance drivability and to provide the driver with a more stable and secure interface for operating the vehicle.

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.

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.

Using a holistic 1D engine simulation approach for the modelling of full-transient engine operation, allows analyzing future engine concepts, including its exhaust gas aftertreatment technology, early in the development process. Thus, this approach enables the investigation of both important fields - the thermodynamic engine process and the aftertreatment system, together with their interaction in a single simulation environment. Regarding the aftertreatment system, the kinetic reaction behavior of state-of-the-art and advanced components, such as Diesel Oxidation Catalysts (DOC) or Selective Catalytic Reduction Soot Filters (SCRF), is being modelled. Furthermore, the authors present the use of the 1D engine and exhaust gas aftertreatment model on use cases of variable valve train (VVT) applications on passenger car (PC) diesel engines.

In-use compliance under LEV III emission standards, GHG, and fuel economy targets beyond 2025 poses a great opportunity for all ICE-based propulsion systems, especially for light-duty diesel powertrain and aftertreatment enhancement. Though diesel powertrains feature excellent fuel-efficiency, robust and complete emissions controls covering any possible operational profiles and duty cycles has always been a challenge. Significant dependency on aftertreatment calibration and configuration has become a norm. With the onset of hybridization and downsizing, small steps of improvement in system stability have shown a promising avenue for enhancing fuel economy while continuously improving emissions robustness. In this paper, a study of current key technologies and associated emissions robustness will be discussed followed by engine and aftertreatment performance target derivations for LEV III compliant powertrains.

Dynamic skip fire (DSF) has shown significant fuel economy improvement potential via reduction of pumping losses that generally affect throttled spark-ignition (SI) engines. In DSF operation, individual cylinders are fired on-demand near peak efficiency to satisfy driver torque demand. For vehicles with a downsized-boosted 4-cylinder engine, DSF can reduce fuel consumption by 8% in the WLTC (Class 3) drive cycle. The relatively low cost of cylinder deactivation hardware further improves the production value of DSF. Lean burn strategies in gasoline engines have also demonstrated significant fuel efficiency gains resulting from reduced pumping losses and improved thermodynamic characteristics, such as higher specific heat ratio and lower heat losses. Fuel-air mixture stratification is generally required to achieve stable combustion at low loads.

The range of tasks in automotive electrical system development has clearly grown and now includes goals such as achieving efficiency requirements and complying with continuously reducing CO2 limits. Improvements in the vehicle electrical system, hereinafter referred to as the power net, are mandatory to face the challenges of increasing electrical energy consumption, new comfort and assistance functions, and further electrification. Novel power net topologies with dual batteries and dual voltages promise a significant increase in efficiency with moderate technological and financial effort. Depending on the vehicle segment, either an extension of established 12 V micro-hybrid technologies or 48 V mild hybridization is possible. Both technologies have the potential to reduce fuel consumption by implementing advanced stop/start and sailing functionalities.

In view of changing climatic conditions all over the world, Green House Gas (GHG) saving related initiatives such as reducing the CO2 emissions from the mobility and transportation sectors have gained in importance. Therefore, with respect to the large U.S. market, the corresponding legal authorities have defined aggressive and challenging targets for the upcoming time frame. Due to several aspects and conditions, like hesitantly acting clients regarding electrically powered vehicles or low prices for fossil fuels, convincing and attractive products have to be developed to merge legal requirements with market constraints. This is especially valid for the market segment of Light-Duty vehicles, like SUV’S and Pick-Up trucks, which are in high demand.

The emission legislations are becoming increasingly strict all over the world and India too has taken a big leap in this direction by signaling the migration from Bharat Stage 4 (BS 4) to BS 6 in the year 2020. This decision by the Indian government has provided the Indian automotive industry a new challenge to find the most optimal solution for this migration, with the existing BS 4 engines available in their portfolio. Indian market for the LCV segment is highly competitive and cost sensitive where the overall vehicle operation cost (vehicle cost + fluid consumption cost) is the most critical factor. The engine and after-treatment technology for BS 6 emission levels should consider the factors of minimizing the additional hardware cost as well as improving the fuel efficiency. Often both of which are inversely proportional. The presented study involves the optimization of after treatment component size, layout and various systems for NOx and PM reduction.