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With more stringent CO2 emission regulation in the world, Plug-in Hybrid Electric Vehicle (PHEV, also known as off-vehicle charging hybrid electric vehicle, OVC-HEV) plays a more important role in the current modern market, such as in China. At the same time, Real Driving Emission (RDE) was introduced in both Euro 6d and China 6b regulation, which covers more factors in the real driving practice including altitude, environment temperature, fuel quality, driving behaviors, and so on, which could potentially impact the pollutant emissions. Besides above mentioned, for PHEV, the state of charge (SOC) of the battery is also considered as one important factor, which could impact the engine load and emissions.

Gasoline particulate filters (GPF) have become a standard aftertreatment component in Europe, China, and since recently, India, where particulate emissions are based on a particle number (PN) standard. The anticipated evolution of regulations in these regions towards future EU7, CN7, and BS7 standards further enhances the needs with respect to the filtration capabilities of the GPFs used. Emission performance has to be met over a broader range in particle size, counting particles down to 10nm, and over a broader range of boundary conditions. The requirements with respect to pressure drop, aiming for as low as possible, and durability remain similar or are also enhanced further. To address these future needs new filter technologies have been developed. New technologies for uncatalyzed GPF applications have been introduced in our previous publications.

The gasoline particulate filter (GPF) represents a practical solution for particulate emissions control in light-duty gasoline-fueled vehicles. It is also seen as an essential technology in North America to meet the upcoming US EPA tailpipe emission regulation, as proposed in the “Multi-pollutant Rule for Model Year 2027”. The goal of this study was to introduce advanced, uncoated GPF products and measure their particulate mass (PM) reduction performance within the existing US EPA FTP vehicle testing procedures, as detailed in Code of Federal Regulations (CFR) part 1066. Various state-of-the-art GPF products were characterized for their microstructure properties with lab-bench checks for pressure drop and filtration efficiency, then pre-conditioned with an EPA-recommended 1500 mile on-road break-in, and finally were tested on an AWD vehicle chassis-dyno emissions test cell at both 25°C and -7°C ambient conditions.

The proposed Euro-7 regulations are expected to build on the significant emissions reductions that have already been achieved using advanced Euro VI compliant after treatment systems (ATS). The introduction of in-service conformity (ISC) requirements during Euro VI paved the way for enabling compliance during real-world driving conditions. The diverse range of applications and resulting operating conditions greatly impact ATS design and the ability of the diesel particulate filter (DPF) to maintain performance under the most challenging boundary conditions including cold starts, partial/complete regenerations, and high passive soot burn operation. The current study attempts to map the particle number (PN) filtration performance of different DPF technologies under a variety of in-use cycles developed based on field-data from heavy duty Class-8 / N3 vehicles.

The ever-tightening regulation norms across the world emphasize the magnitude of the air pollution problem. The decision to leapfrog from BS4 to BS6 – with further reduction in emission limits -showed India’s commitment to clean up its atmosphere. The overall cycle emissions were reduced significantly to meet BS6 targets [1]. However, the introduction of RDE norms in BS6.2 [1] demanded further reduction in emissions under real time operating conditions – start-stop, hard acceleration, idling, cold start – which was possible only through strategies that demanded a cost effective yet robust solutions. The first few seconds of the engine operation after start contribute significantly to the cycle gaseous emissions. This is because the thermal inertia of the catalytic converter restricts the rate at which temperature of the catalyst increases and achieves the desired “light-off” temperature.

Adaption of EV powertrains in existing vehicle architecture has created many unique challenges in meeting performance, reliability, safety, ease of manufacturing & serviceability at optimum cost. Mounting of large size battery packs in existing vehicle architecture is one of them. Specific energy & the energy density of Lithium ion batteries are very lower compared to Diesel & Petrol, which requires high volume & weight for equivalent energy storage. For movement of many passengers and to ensure sufficient range EV buses typically needs large amount of energy and for storage of same bigger size battery packs are required. These large size batteries directly affect vehicle architecture, seating layout, ease of assembly & serviceability. Moreover the heavy mass of batteries directly influences vehicle dynamics & performance characteristics such as vehicle handling, roll & NVH. The most important consideration in design of EV vehicles in general and buses in specific is safety.

There is need of the hour to reduce greenhouse gases and become carbon neutral. Global warming and the increase in pollution are big threats to humankind. The Paris agreement is a major step towards reducing pollution and greenhouse gases. To improve the situation, hydrogen fuel cell electric vehicle is a promising technology that enables zero emissions, zero greenhouse gas generation and high efficiency with superior performance for long-range applications as compared to other green technologies. Although it is a promising and beneficial technology, there is limited information available in the public domain about fuel cell technology and its accessories. Air intake and cooling system’s right functioning is very important for proper fuel cell functioning. Incoming air to the fuel cell stack needs to be processed by cleaning, humidifying, cooling or heating. If the incoming air isn't clean, it will deteriorate the fuel cell's performance; it may get blocked, or even damaged.

To meet future emission levels, the automotive industry is trying to reduce tailpipe emissions through both possible pathways, i.e. emission from engines as well as and the development of novel catalytic emission control concepts. The present study will focus on the close coupled SCR on Filter commonly known as SDPF which is a main pathway to reduce NOx along with particulate mass and number for light duty passenger cars and sport utility vehicles for BS 6 RDE/OBD 2 and future legislation like BS-7. The SDPF is a challenging technology as it is critical component in exhaust after treatment system involving in NOx and PM/PN reductions hence careful optimization of this technology is necessary in terms of space velocity requirements, temperature, feed NOx emission levels, particulate mass and ash holding capacities, NH3 storage on the SDPF, and back pressure.

The auto industry is one of the major contributors for noise pollution in urban areas. Specifically, highly populated heavy commercial diesel vehicle such as buses, trucks are dominant because of its usage pattern, and capacity. This noise is contributed by various vehicle systems like engine, transmission, exhaust intake, tires etc. When the pass by noise levels exceeds regulatory limit, as per IS 3028, it is important for NVH automotive engineer to identify the sources & their ranking for contribution in pass by noise. The traditional methods of source identification such as windowing technique, sequential swapping of systems and subsystems which are time consuming.Also advanced method in which data acquisition with a synchronizing technology like telemetry or Wi-Fi for source ranking are effective for correctness.However they are time and resource consuming, which can adversely impact product development timeline.

Worldwide automotive sector regulatory norms have changed and become more stringent and complex to control environmental noise and air pollution. To continue this trend, the Indian Ministry of Road Transport is going to impose new vehicle exterior pass-by noise regulatory norms IS 3028:2023 (Part2) to control urban area noise pollution. This paper studies the synthesis of M1 category vehicle driving acceleration, dominant noise source, and frequency contribution in exterior PBN level. A vehicle acceleration analysis study was carried out to achieve an optimized pass by noise (PBN) level based on the vehicle’s PMR ratio, reference, and measured test acceleration data. Based on the analysis, test gear strategy was decided to achieve a lower PBN level. This strategy involved increasing the effective final drive ratio and optimizing engine calibration, resulting in improvement with acceleration in the ith gear.

A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers.

Since last decade automotive Industry is witnessing transition from ICE to EV due to stringent environmental laws by government bodies and technological breakthrough. EV technology is emerging day by day. Biggest challenge in front of OEM is the phase shift from ICE to EV. OEM need to decide on glide path for test rig development for this change to support ICE & EV powertrain validation to deliver reliable product to their customers. In EV development, major focus is on investment for battery development. Hence, for the Motor and Gearbox validation balanced approach is to upgrade existing ICE test bench for the EV with minimum effort and cost. This paper provides details on need and approach required to make the ICE test bench capable for EV powertrain validation. Proposed methodology helps to support both type of powertrain and have maximum utilization of the test bench.

The automotive world is rapidly moving towards achieving shorter lead time using high-end technological solutions by keeping up with day-to-day advancements in virtual testing domain. With increasing fidelity requirements in test cases and shorter project lead time, the virtual testing is an inevitable solution. This paper illustrates method adopted to achieve best approximation to emulate driver behavior with 1-D (one dimensional) simulation based modeling approach. On one hand, the physical testing needs huge data collection of various parameters using sensors mounted on the vehicle. The vehicle running on road provides the real time data to derive durability test specifications. One such example includes developing duty cycle for powertrain durability testing using Road Torque Data Collection (RTDC) technique. This involves intense physical efforts, higher set-up cost, frequent iterations, vulnerability to manual errors and causing longer test lead-time.

As the official proposal for emission regulation Euro 7 has been released by European Commission, PN above 10nm is taken into consideration for the ultrafine particulate emissions control. The challenges of GPF filtration efficiency emerge for the light-duty manufactures to meet the future emission standards. In the present study, a China 6 compliant vehicle was tested to reveal its performance over the China 6 standards and potential to meet the upcoming Euro 7. Three GPF product types (Gen 1, Gen 2, and concept Gen 3) were mounted to the tested vehicle. WLTC tests were conducted on chassis dynamometer in laboratory as well as a self-designed aggressive cycle (“Base Cycle”) tests. To explore the GPFs performance for PN emissions above 10nm against the proposed limit 6.0E11 #/km, PN emission above 10nm were measured in our laboratory tests for both engine out and tailpipe as well as the PN emission above 23nm.

As in the past several years, we provide here an overview of recent major regulatory and technological changes for reducing emissions from the transport and off-road sector. In the past, this review was focused mostly on improvement in engine efficiency and tailpipe emissions of criteria pollutants. However, starting last year [1] we have increased the scope to broadly address the increased focus on greenhouse gas emissions and the emergence of various non-conventional fuel pathways to achieve the various decarbonization goals. There are two broad themes that are emerging, and which we describe here. Firstly, that we are approaching the implementation of the last of the major regulations on criteria pollutant emissions from cars and trucks, led by Europe, through Euro 7 standards and US, through multi-pollutant standards for light- and heavy-duty vehicles.

RDE test has been introduced to the light-duty vehicle certification process in both China 6 and Euro 6d standards. The RDE test shall be performed on-road with PEMS, which is developed to complement the current laboratory certification of vehicles and ensure cars to deliver low emissions under more realistic on-road driving conditions. Particulate matter has been highly perceived as a significant contributor to human health risks and thus strictly regulated globally. For the RDE evaluation, the MAW method used by the China 6 standard is usually found less stringent than the RMA method used by the Euro 6d standard. In the present study, both of the MAW and RMA methods were applied to different driving cycles and operating conditions, which met the general RDE test requirements, yet resulted in different evaluated PN results.

This review covers advances in regulations and technologies in the past year in the field of vehicular emissions. We cover major developments towards reducing criteria pollutants and greenhouse gas emissions from both light- and heavy-duty vehicles and off-road machinery. To suggest that the transportation is transforming rapidly is an understatement, and many changes have happened already since our review last year [1]. Notably, the US and Europe revised the CO2 standards for light-duty vehicles and electrification mandates were introduced in various regions of the world. These have accelerated plans to introduce electrified powertrains, which include hybrids and pure electric vehicles. However, a full transformation to electric vehicles and the required grid decarbonization will take time, and policy makers are accordingly also tightening criteria pollutant standards for internal combustion engines.

With India achieving the BSVI milestone, the diesel particulate filter (DPF) has become an imperative component of a modern diesel engine. A DPF system is a device designed to trap soot from exhaust gas of the diesel engine and demands periodic regeneration events to oxidize the accumulated soot particles. The regeneration event is triggered either based on the soot mass limit of the filter or the delta pressure across it. For a Heavy Duty Diesel Engine (HDDE), pressure difference across the DPF is not usually reliable as the size of the DPF is large enough compared to the DPF used ina passenger vehicle diesel engine. Also, the pressure difference across DPF is a function of exhaust mass flow and thus it makes it difficult to make an accurate call for active regeneration. This demands for a very accurate soot estimation model and it plays a vital role in a successful regeneration event.

India BS6 Stage2 (2023) regulations demand all gasoline direct injection (GDI) vehicles to meet particulate number emissions (PN) below 6x10+11# per km. Gasoline particulate filters (GPF) are a proven technology and enable high PN filtration efficiencies throughout the entire vehicle lifetime. One challenge for GPF applications could be the changing emission performance characteristics as a function of mileage due to collected ash and/or soot deposits with implications on back pressure losses. The main objective of this technical contribution is to study the above-mentioned challenges while applying Indian driving conditions and typical Indian climate and other ambient conditions. The substrate technology selected for this study is a high porosity GPF designed to enable the integration of a three-way functionality into the GPF, commonly described as catalyzed GPF (cGPF).

Error in suspension asymmetry or tire parameters may lead to vehicle drifting laterally from its intended straight-line path, which is called vehicle pull. Driver then needs to apply constant steering correction to maintain the vehicle in straight line which will lead to high driver fatigue and deteriorate driving experience. Manufacturing a perfectly symmetric suspension system is impractical, however an insight into the manufacturing tolerances of suspension system at the early design stage can be extremely useful. Also tire force and moment parameters at straight line operation and its maximum allowable variations will help in defining the tire parameter specifications and tolerances. The objective of this study was to develop a 1D model of suspension and tire system which can predict the torque experienced in steering and drift of the vehicle from straight line due to the tire force and moment and asymmetric suspension geometry.