Browse Topic: Emissions control

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CS Structure: New generation metallic catalyst substrate for 2- and 3-Wheeler applications2026-26-0220To be published on 01/16/2026
Affordable, efficient and durable catalytic converters for the two and three-wheeler industry in developing countries are required to reduce vehicle emissions and to maintain them at a low level; and therefore to participate in a cleaner and healthier environment. Especially, Metallic catalyst substrates from Emitec Technologies GmbH with structured foils like the Longitudinal StructureTM (LS) are fully compatible to this effort with more than 90% share of produced 2/3 Wheelers metallic catalyst substrates for the Indian customers in 2024. One decade after the market introduction of this LS structure, Emitec Technologies GmbH will introduce now a new generation of foil structure: the Crossversal StructureTM (CS) that improves further the affordability, the efficiency of metallic catalytic converters, keeping the durability at same level than previous substrate generation. The paper will briefly review the development of metallic substrates for 2/3 wheelers applications, especially the
Jayat, Francois
Introducing a new catalyst family in gasoline aftertreatment2026-26-0231To be published on 01/16/2026
This paper is to introduce a new catalyst family in gasoline aftertreatment. Indeed, it has been shown that under certain driving conditions, three-way catalysts produce significant amounts of toxic NH3 and the strong greenhouse gas N2O, which are both very unwanted emissions. In a self-committed approach, OEMs could want to minimize these noxious pollutants, especially if this can be done with no architecture change, namely without additional underfloor catalyst. In this paper we will compare different approaches: regular underfloor TWC, SCR derived from diesel aftertreatment, gasoline dedicated Ammonia Slip Catalyst (ASC) and especially developed novel gasoline Secondary Emission Treatment (SET) catalyst, providing both ammonia abatement and underfloor three-way functionality. The data will show that SCR only reduces NH3 from a passive SCR reaction in a limited amount in the cold start including the need of oxygen presence, namely secondary air introduction. ASC is efficient in cold
Kuhn, Sebastian, Magar, Avinash, Kogel, Julius, Lahousse, Christophe
A Thermoelectric System for Emission Control Optimization in Two-Wheeler Automotive Applications2026-26-0218To be published on 01/16/2026
Environmental pollution is one of the growing concerns of our society. As vehicle emissions are a major contributor to air pollution, emission control is a primary goal of the Automotive industry. Vehicle emissions are higher due to improper combustion, which leads to toxic gases being generated from the exhaust system. Unburnt fuel is one of the leading causes of toxic pollutants such as Carbon Monoxide, Nitric Oxides (NOx) and Hydrocarbons. The catalytic converter converts these gases into less toxic substances such as Carbon Dioxide, Nitrogen, and water vapor. The catalytic converter performs efficiently after reaching its “Light Off” temperature, after which the catalyst becomes active. Hence, elevated temperature of the exhaust gases aids in efficient conversion. Presently, the gases from the exhaust system are approximately at a temperature of 300°C-600°C. This paper outlines the concept of a Peltier (Thermoelectric) Module - based system, which helps maintain the high
Venkateshwaran, Aishwarya, soodlu, Shashikiran, M, Mathaiyan
A Physics-Guided Neural Network Approach for EGR Cooler Temperature Estimation: Addressing ECU Model Discrepancies2026-26-0435To be published on 01/16/2026
As the automotive industry explores alternative powertrain options to curb emissions, it is pertinent to refine existing technologies to improve efficiency. The Exhaust Gas Recirculation (EGR) system is a pivotal component in emission control strategies for Internal Combustion Engines (ICE). The EGR cooler is crucial in thermal management strategies, as it lowers the temperature of recirculated exhaust gases before feeding it along with fresh air, thereby reducing nitrogen oxides (NOx) emissions. Precise estimation of the EGR cooler outlet temperature is crucial for effective emission control. However, conventional Engine Control Unit (ECU) models fall short, as they often show discrepancies when compared to real-world test data. These models rely on empirical relationships that struggle to capture, transient effect, and real time variation in operating conditions. Consequently, ECU-based estimations of EGR Cooler outlet temperature frequently deviate from actual values, leading to
Kumar, Amit, Kumar, Raman, Manojdharan, Arjungopal, Challa, Krishna, Kramer, Markus
Design & Optimization of CV shaft system to address powertrain induced NVH issues2026-26-0336To be published on 01/16/2026
The automotive industry is a crucial sector that plays a significant role globally. Government policies have a profound impact on this automotive industry in defining the regulatory standards and emission controls. Such regulations incentivized automakers to invest in research and development complying those standards towards reduction of vehicle emission which intern result in higher torsional vibrations and excitations amplitudes. To address the rising NVH related concerns in driveline system. Drive shafts (CV shafts) is an important component in power-train system in vehicle. Drive shaft’s main purpose to transfer torque from engines to wheels at multiple speeds with different articulation angles. The roughness generated by the engine follows a transfer path from engine to transaxle and transaxle to half shafts in monocoque vehicles which generates discomfort to the drivers whenever the vehicle is driven. The roughness can also be addressed by proper design of driveshaft stiffness
M A, Abdul Azarrudin, Jayachandran, Suresh kumar, KUMAR, SHIVANI, Bhardwaj, Kinshuk, M, DEVAMANALAN, Kanagaraj, Pothiraj
Leveraging Advanced AI/ML Algorithms to Derive Actionable Insights from Fleet Vehicle In-Use Performance Ratio Monitoring (IUPRm) Data2026-26-0637To be published on 01/16/2026
In recent years, growing concerns over environmental pollution have led to the implementation of increasingly stringent emission regulations worldwide. These regulations require not only the reduction of pollutant emissions but also robust monitoring of critical emission control components under real-world driving conditions. The In-Use Performance Ratio Monitoring (IUPRm) framework quantifies how frequently onboard diagnostic systems evaluate these components within defined operational boundaries for each vehicle. IUPRm is organized into several monitoring groups, including catalyst monitoring, oxygen sensor monitoring, exhaust gas recirculation (EGR) monitoring, and gasoline particulate filter monitoring. The specific groups and monitoring requirements vary based on fuel type (gasoline or diesel), engine technologies (such as variable valve timing or EGR), and exhaust system configurations (single or dual bank). For automakers, analyzing these parameters across large vehicle fleets
Ghadge, Ganesh Narayan, Jadhav, Marisha, Hosur, Viswanatha
Optimization of Negative Crankcase Pressure Mechanism to Minimize Oil Pumping into Combustion chamber and Ensure Particulate Number Compliance in Euro VI Emission for Naturally Aspirated Gas Engine.2026-26-0223To be published on 01/16/2026
Emissions regulations, such as Euro VI, drives the Automotive industry to innovate continuously in Engine development. One significant challenge is the engine oil pumping from the crankcase into the combustion chamber, where it participates in combustion, which contributes to increased Particulate Numbers and fails to meet Euro VI emission compliance. This issue is most noticeable during engine idling and motoring conditions. During this time, a higher negative pressure difference develops between the intake manifold, which is acting above the combustion chamber and the engine crankcase. Within the crankcase, engine oil is present along with aerosols carried in the blow-by gas. This pressure difference causes oil passes through piston rings during suction stroke and valve stem seals in Naturally Aspirated Gas engines. The impact of the pressure difference between the intake manifold and crankcase was studied by varying the crankcase pressure through crankcase ventilation system. The
R, MAHESH BHARATHI
Emerging Trends in Emission Optimization2026-26-0229To be published on 01/16/2026
The exhaust emission control is a vital aspect of automotive development, aimed at ensuring effective control of pollutants such as NOx, CO, and HC. The traditional method of calibrating emission control strategies, that requires extensive vehicle testing with both the fresh and aged catalysts under a variety of operating conditions, is a time-consuming process. The frequent changes in emission legislation creates new challenges for achieving a faster time to market and effective utilization of resources. So, the use of automation and machine learning (ML) in the domain of emission control is the need of the hour to proactively tackle these challenges. This paper attempts to explore emerging trends in emission optimization, such as the automated measurement process and ML/AI based data analysis, that can improve the overall process efficiency in the calibration of emission control strategies. The automated measurement process is achieved using the automation software. The data
Dhayanidhi, Hukumdeen, Balasubramanian, Karthick, A, Akash
All New 1.2L Turbocharged Gasoline Direct Injection Engine from Tata Motors2026-26-0071To be published on 01/16/2026
A continuous stress on meeting stringent emissions regulations alongside rising consumer expectations for enhanced driving performance and refinement on powertrain applications on passenger cars. To address this customer aspirations Tata Motors has engineered the advanced 1.2L 3-cylinder turbocharged gasoline direct injection engine HYPERION. This next-generation powertrain is designed to maximize efficiency, lower emissions and deliver superior performance with improved noise, vibration, and harshness (NVH) characteristics. Key innovations includes highly optimized fuel injectors injector operating at 35 MPa, CVO-3 (3rd Gen Controlled Valve Operation), Miller Cycle with Electrically actuated VGT turbocharger and an AI-enabled engine management system, which collectively enhances efficiency and performance. The exhaust after-treatment system incorporates a Three-Way Catalyst (TWC) and an integrated Four-Way Conversion Catalyst (FWC+TM) for efficient emission control. The BS6 phase 2
Hosur, Viswanatha, Ghadge, Ganesh Narayan, Joshi, Manoj, Jadhav, Aashish, Panwar, Anupam
Drive Cycle Type Identification Using Data Driven Methodologies2026-26-0649To be published on 01/16/2026
Identifying the type of drive cycle is crucial for analyzing customer usage and optimizing vehicle performance and emission control. Methods that rely on geographical location are limited by varying driving conditions at the same location (e.g., heavy traffic during peak hours vs. free-flowing traffic at night). This paper proposes a methodology to identify the type of drive cycle (city, interurban, highway or others) using drive characteristics derived from vehicle data rather than geographical location. Real-world vehicle data from testing trucks is taken, whose drive profiles are already known. Initially, multiple characteristic features of the drive cycle are identified from literature surveys and domain experiences. These features, which can be extracted from basic signal data, include gear shifts, time spent in different driving modes (acceleration, cruise, standstill), velocity distributions, and an 'aggressiveness factor' representing overall driving style. Using ML based
REDDY, MALLANGI PRASHANTH, Gorain, Raju, Ganguly, Gourav
Niobium Alloyed Brake Disc for reduced NVH and emission control2026-26-0285To be published on 01/16/2026
Recent regulations limiting brake dust emissions have presented many challenges to the brake engineering community. The objective of this paper is to provide a low cost, mass production solution utilizing well known existing technology to meet brake emissions requirements. The proposed process is to alloy the Gray Cast Iron with Niobium. The Niobium addition will reduce wear debris and improve NVH (Noise Vibration Harshness). The test methodology included: Manufacture of disc samples alloyed with Niobium, and Evaluation of airborne wear debris utilizing a pin-on-disc tribometer equipped with emission collection capability. The airborne emission and wear surfaces were further analyzed by Scanning Electron Microscopy, Energy Dispersive techniques (SEM-EDS), X-Ray Diffraction and Optical Microscopy. The cast iron test matrix included four groups; Unalloyed eutectic 4.3% Carbon Equivalent (CE), Unalloyed hypereutectic >4.3% CE, Niobium alloyed Eutectic and Niobium alloyed hypereutectic
Barile, Bernardo, Holly, Mike
Development of a Passive Regeneration Diesel Particulate Filter System for an Agricultural tractor Engine2026-26-0217To be published on 01/16/2026
This paper presents the development and evaluation of a passive regeneration Diesel Particulate Filter (DPF) system for a 4-cylinder, 3.18-liter naturally aspirated agricultural tractor engine based on the mDI engine family. The primary objective is to significantly reduce particulate matter (PM) emissions while maintaining optimal engine performance and fuel economy. The passive regeneration DPF system leverages the engine's operating conditions to generate sufficient heat for the oxidation of trapped particulate matter, eliminating the need for active regeneration techniques. The paper details the design process, including the selection of DPF material, filter geometry, and integration into the exhaust system. Rigorous experimental testing was conducted to assess the performance of the DPF system under various engine load and speed conditions. Results demonstrate substantial reductions in PM emissions without compromising engine power, torque, or specific fuel consumption. This
Maddali, Varun Suman, Jidigonti, Shashank, Kannan, S, Ramesh, Natrajan
Optimising Hydrogen Engine Performance: A Comparative Study of Lean and Stoichiometric Calibration Approach2026-26-0261To be published on 01/16/2026
Hydrogen combustion in internal combustion engines offers numerous advantages, such as zero CO2 emissions and high flame speed, which make it a promising alternative fuel for green vehicle solutions. In order to maximize the engine performance with hydrogen, however, meticulous calibration of the air-fuel mixture must be performed, particularly when lean and stoichiometric combustion conditions are considered. Lean burning, i.e., excess air, offers better thermal efficiency and lower NOx emissions but can cause lower engine power and combustion instability. Stoichiometric combustion, however, ensures a complete fuel-air mixture but at the cost of higher combustion temperature and high NOx emissions. Calibration strategies for hydrogen engines are presented in this paper by comparing the lean and stoichiometric strategies and their implications on engine power output, efficiency, and emissions. Test data from several hydrogen engine configurations demonstrate that lean burn with EGR
Jadhav, Ajinkya, Bandyopadhyay, Debjyoti, Sutar, Prasanna S, Sonawane, Shailesh Balkrishna, Rairikar, Sandeep D, Thipse, Sukrut S
Development of high BMEP natural gas engine with knock mitigation2026-26-0121To be published on 01/16/2026
The stringent emission norms over the past few years have driven the need to use low carbon fuels and after treatment technology. Natural gas is a suitable alternative to diesel for heavy duty engines with applications in power generation and transportation sectors. Stoichiometric combustion mode offer the advantages of complete combustion and low carbon dioxide emissions. The combination of turbocharging and cooled exhaust gas recirculation (EGR) technology enhances the power density along with reduced exhaust emissions simultaneously. However, there are several constraints in the operation of natural gas spark ignition engine such as exhaust gas temperature (EGT) limit of 750 °C, sufficient before turbine (BT) pressure for EGR drivability, boost pressure (2.5 bar), peak cylinder pressure limit and knocking. These limits may restrict the brake mean effective pressure (BMEP) of the engine. In the present study, tests were conducted on a V12, 24 litre, dedicated heavy duty natural gas
Khaladkar, Omkar, Marwaha PhD, Akshey
Engine and After-treatment optimization using Simulation tools2026-26-0057To be published on 01/16/2026
To achieve world-class engineering quality and reduce the effort and cost associated with conventional techniques, it is essential to incorporate digital validation during the development and validation phases. This research paper explores the methodologies and applications of advanced simulation tools for creating models of engines and their sub-components using MATLAB/Simulink, parameterizing these systems with AVL CruiseM, and operating them using ETAS Labcar-Operator. The paper provides an in-depth analysis of optimizing engine and after-treatment parameters, demonstrating their impact on performance and environmental compliance. It presents a series of simulation case studies that illustrate the effects of different parameter settings on the efficiency and emission levels of diesel passenger and commercial vehicle engines. These case studies highlight the overall workflow of model-based system development, emphasize various development milestones, and correlate these with actual
Shukla, Saurabh, Shilledar, Aneesh
Legislative Framework and Emission Testing using PEMS for NRMM (Non-Road Mobile Machinery) in India: A Technological Perspective2026-26-0139To be published on 01/16/2026
Emission Regulations for NRMM in India have evolved significantly over past two decades. India has progressively adopted stricter standards to align with global best practices. The latest regulations have introduced stringent caps on particulate matter (PM), nitrogen oxides (NOx), and other pollutants, ensuring compliance with environmental sustainability goals. Future legislative frameworks are expected to impose even more rigorous emission limits, focusing on further reduction of NOx and PM levels while incorporating real-world emission monitoring. This will require manufacturers to integrate advanced after-treatment systems and adopt cleaner combustion technologies to meet compliance standards. To validate compliance with these stringent limits, rigorous testing methodologies are employed. Portable Emission Measurement Systems (PEMS) have become a crucial tool for real-world emission assessment. PEMS technology allows for on-road and field testing of NRMM under actual operating
Rastogi, Aadhar, Garg, Varun, Ragot, Nicolas
Investigation on Degradation Process of PdRuIr/CZ “Pseudo-Rh” Catalysts Used for Motorcycles2024-32-001604/18/2025
Platinum (Pt), palladium (Pd), and rhodium (Rh) are used as active substances in exhaust gas purification catalysts for automobiles. Among these, Rh is an essential element because it efficiently promotes a NOx reduction reaction. On the other hand, the price of Rh has been rising in recent years. From the perspective of the supply risk of rare resources, there is an urgent need to develop technologies to replace or reduce the amount of Rh used in catalysts. We focused on the pseudo-rhodium alloy developed by the ACCEL program of the Japan Science and Technology Agency (JST), and then investigated the application of the pseudo-rhodium alloy on the catalysts of our motorcycles and also the degradation process. A nanosized PdRuIr alloy supported on a ceria-zirconia solid solution (PdRuIr/CZ) was prepared and assembled into a motorcycle for emissions measurement. The PdRuIr/CZ catalyst with an alloy loading of 4.0 g/L had initial properties comparable to the Rh supported on a CZ (Rh/CZ
Motegi, Takuya, Tatara, Shunya, Takamoto, Shunpei, Doi, Kosuke
Experimental Study of Port Water Injection System on Single Cylinder Diesel Engine Performance and Exhaust Emission2024-32-002504/18/2025
Vehicle emission standards have become more and more stringent and have driven the development of advanced engine design with low-cost emission control technologies. For small diesel engine which is used in three-wheel (3W) passenger and load carrying vehicles, it was major task to improve lower engine rpm torque and performance to comply with stringent exhaust emissions standard as well, especially for Oxides of Nitrogen (NOx) and Particulate Matter (PM) emissions. Bharat Stage (BS) VI emission standards for three-wheel vehicles was implemented from April 2020 onwards in India. Water injection technology has proven advantageous for low-cost solution with Mechanical fuel injection system on small diesel engines, Intake port water injection is the easiest method to introduce water to engine cylinder, which calls for minimal modification of existing engine structure. In the present study 435cc naturally aspirated DI Diesel engine used for three-wheel vehicle was explored by adding water
Syed, Kaleemuddin, Chaudhari, Sandip, Khairnar, Girish, Katariya, Rahul, Jagtap, Pranjal, Bhoite, Vikram
Three way Catalyst with faster light-off substrates – A promising approach to reduce tailpipe emissions2024-26-014201/16/2024
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. However, the introduction of RDE norms in BS6.2 demanded further reduction in emissions under real time operating conditions - start-stop, hard acceleration, and 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 to major amount 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. The challenge becomes more prominent in the turbocharged engines which puts additional heat 'loss
Kale, Vishal Maruti, M, Ravisankar, Hosur, Viswanatha, Sridhar, S, Bhimavarapu, Aditya, Lende, Nilesh Ashok, Rose, Dominik, Tao, Tinghong
Experimental Investigation on Emission Characteristics of a GDI Engine with ethanol-blended gasoline Fuels2024-26-015501/16/2024
Ethanol-gasoline blended fuels have been widely implemented in Indian markets followed by the GOIs road map as ethanol reduces life-cycle greenhouse gas emissions and improves anti-knock performance. However, its effects on engine out emissions including particulate matter (PM) from gasoline direct injection (GDI) engines still need further investigation. In this study, the effect of ethanol blended gasoline fuels with various blended rates (0%, 10%, 20%) on emissions and catalyst conversion efficiencies on a 1.2-liter 3-cylinder turbo GDI miller cycle engine is investigated. The addition of ethanol to gasoline fuel enhances the RON of the blended fuels, and oxygen content and changes the distillation temperature. Advancing Ignition timing, lambda biasing, Mode based SOI has been tested. Test bench results indicated that with the E10 blend all pollutant conversion is at 98% in all operating points. With E20 blend the NOx emission conversion efficiency is dropped to ~60%. However, this
R, Navaneetha kannan, S, Easwar Ram, S, Satish Kumar, Karthi, Ramanathan, Ramakrishnan, Muthu
Engine Modelling with Smart Online DoE2024-26-033801/16/2024
The implementation of TREM/CEV 5 emission norms on farm equipment will bring in cost pressure due to the need for exhaust after treatment systems. This cost increase needs to be reduced by bringing in more efficient and effective processes to shorten the development phase and to provide better fuel efficiencies. In this work ETAS ASCMO Online DoE with Constraint Modelling (ODCM) to execute smart online DoE on a new common rail diesel engine with EGR, whose exact bounds of operation was not available. A Global test plan with ASCMO Static was created without much focus on detailed constraints of engine operation, other than the full load curve. The parameters which were selected were Speed, Torque, Rail Pressure, Main Timing, EGR Valve Position, Pilot Separation and Quantity and Post Quantity and Separation. For these parameters, the safe operating bounds were not available. This ASCMO Static test plan is automated and executed on engine test cell with ETAS INCAFlow. ODCM at each step
Paulraj, Lemuel Srinivasan, Varsha, Anuroopa, Karadi, Subramanya, KUMAR, DEVENDRA
A mechanism to maintain negative crankcase pressure in a turbocharged gas engine to meet Euro-VI emission regulation and to reduce oil consumption.2024-26-014501/16/2024
Emissions regulation continually drives the automotive industry to innovate and develop. This pushes to introduce mechanism to maintain negative crankcase pressure in gas engine to meet this changing regulation. The way a turbocharger is used, to meet engine performance, can impact the pressure balance over the compressor and turbine end seals. This pressure difference can allow oil to leak through turbocharger seals. In normal engine operating condition, the pressure in the turbocharger end housings is higher than the bearing housing and oil/gas flows into the bearing housing, through the oil drain to the crankcase. Under certain operating conditions, such as low idle and thermal management, this pressure difference can be reversed with a higher bearing housing pressure than the pressure behind the turbine compressor wheel. Under this condition oil/gas will flow out of the bearing housing to the recess behind the compressor wheel. The bearing housing pressure will always track the
R, MAHESH BHARATHI
Experimental And Numerical Investigation of a Single-Cylinder Methanol Port-Fuel Injected Spark Ignition Engine for a Heavy-Duty Applications.2024-26-007201/16/2024
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. Increase of the EGR ratio at stoichiometric operation led to 3
Singh, Inderpal, Güdden PhD, Arne, Raut PhD, Ankit, Emran, Ashraf, Dhongde PhD, Avnish, Sharma, Vijay, Wagh, Sachin
Design And Development of EGR Valve Controller for Bench Test2024-26-034801/16/2024
Various emission and fuel economy norms have been introduced worldwide by governments. In India, meeting each revision of Bharat Stage (BS) emission standards and Corporate Average Fuel Economy (CAFE) norms is challenging and requires new technologies to be incorporated in IC engines. One such technology used in gasoline engines is EGR (Exhaust gas recirculation). It works by recirculating exhaust gases back into the engine in turn increasing fuel economy and reducing nitrogen oxide emissions. An electronic control unit (ECU) precisely controls EGR valve via stepper motor, regulating the flow of exhaust gases into the engine. Lead screw type unipolar stepper motor is commonly used for the same. Vehicle ECU calculates optimum EGR percentage and decides valve opening, further sequentially engaging stepper motor coils to advance or retract the EGR valve. With advancements in EGR technology there still exists few developmental challenges like operating the EGR valve on a test bench setup
Bhatt, Pancham, kumar, krishan, Kumar, Sahil
Optimised Air Management System for Heavy Duty Hydrogen Engines2024-26-017101/16/2024
Many Indian cities are amongst the most polluted cities in the world. Transport sector is identified as one of the major contributors to air pollution. Following the global trend Government of India is also promoting Near Zero Emission fuels with zero CO2 emissions as a way forward to solve the emission problem. With it's policies like Green Hydrogen Mission GOI plans to accelerate the adoption of Hydrogen as fuel in the country. These initiatives have created a breakthrough in development of Hydrogen ICE's by the Indian OEM's. Hydrogen ICE have NOx emissions as the most prominent engine out emissions. NOx emission in Hydrogen engines are very sensitive to operating lambda where after a certain threshold lambda the emissions rise significantly. Therefore the air management system pays a very important role in the hydrogen engine performance & NOx emissions. The study evaluates the various options in turbo charging system for heavy duty Hydrogen engine. As first step 1 stage Variable
Emran, Ashraf, Jagodzinski, Bartosch, Sreedharan, Sajil N, Paranjape, Sumeet, Garg, Shivam, Wagh, Sachin, Sharma, Vijay
GPF : An effective technology to minimize 2Wh particulate emission2024-26-014001/16/2024
India is the world's largest two-wheeler (2Wh) market. With the proportion of its middle class rapidly rising, 2Wh sales and the resulting emissions, are expected to grow exponentially. The decision to leap-frog from BSIV to BSVI emission norms shows India's commitment to clean up its atmosphere. As of now, the regulation mandates Gaseous Pollutant (CO, HC, NOx) emission limits for all 2Whs. However, only 2Whs powered by Direct Injection (DI) engines have a particulate limit (PM & PN). Also, most of the 2Whs manufactured in India are powered by gasoline engines using the Port Fuel Injection (PFI) technology, and hence by definition particulate emission limits do not apply. Particulates when inhaled - especially of the ultrafine sizes capable of entering the blood stream - pose a serious health risk. Therefore, it became imperative to investigate the particulate emission levels of the 2Whs. We conducted a study selecting a motorcycle each from two different vehicle categories - Class 1
Bhimavarapu, Aditya, Singh, Sunil Kumar, Kataria, Rohit, Rose, Dominik, Boger, Thorsten
Desensorization: A Novel Method for Urea Concentration Deterioration Detection in BSVI Engines2024-26-015401/16/2024
Urea concentration deterioration detection in BSVI engines is vital for maintaining compliance with emission regulations. This paper introduces a groundbreaking desensorization method, which offers numerous benefits in detecting urea concentration deterioration by estimating the drop in catalyst conversion efficiency. Traditionally, urea quality sensors have been employed to measure the absolute concentration of urea in the aqueous solution (Diesel Exhaust Fluid – DEF). This information is used to detect usage of poor quality DEF. However, desensorization eliminates the need for dedicated sensors, reducing complexity, cost, and potential sensor-related errors. The proposed method leverages the strong relationship between catalyst conversion efficiency and urea concentration. By monitoring catalyst inlet and outlet NOx values using NOx sensors, the efficiency of the catalyst can be estimated. This estimation allows for the detection of urea concentration deterioration, ensuring that NOx
Venkat, Harish, Kumar, Gokul Elumalai, Kumar, Kosalaraman, G, Vijayakumar
Study of changes in Exhaust after treatment system components in M & N category vehicles from RDE Monitoring stage to RDE Compliance stage2024-26-015001/16/2024
Bharat Stage VI emission norms were implemented in India in two stages: Stage I from 1st April 2020 and Stage II from 1st April 2023. For M & N category vehicles, RDE test along with other applicable certification tests is mandatory for obtaining a BSVI compliance certificate during stages I and II. The RDE test is conducted on the roads in real driving conditions, unlike the Type-I test using a pre-defined cycle on the chassis dynamometer, during which the ambient temperature and other environmental conditions are controlled in a narrow range. During BSVI Stage I for the RDE test, there was no limit for any pollutant. So, it is considered an RDE monitoring stage, and from BS VI Stage II, limits are enforced on a few pollutants (NOX and PN) as notified in notification GSR 226(E) dated March 27, 2023. So, it is considered the RDE compliance stage. During the RDE monitoring phase, emissions from M & N category vehicles are comparatively higher because of several reasons like cost
SINGH, Abhay Pratap, Bathina, Revanth Kumar, Thakare, Kiran Prabhakar
SDPF Application DOE For BS6 RDE/OBD2 using MATLAB/SGB/ETB/CDT2024-26-016101/16/2024
To meet future emission levels, the industry is trying to reduce tailpipe emissions by both, engine measures 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. 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 profile wrt to NOx conversion, Raw NOx concentration, Particulate mass and Ash holding capacities, NH3 storage requirements, back pressure and so on. With BS6 RDE having extremely challenging CF for NOx equals to 1,43, the SDPF design & optimization is high on importance and to demonstrate the success of
Singh, Shephali, Patil, Sandip, Maynal, Rajesh A., Maske, Vidyasagar, Seyler, Michael, Subramanian, Senthilnathan, Deshpande, P V, Luquman, Shahid
An Experimental Study on Soot Particles Size Distribution and Nanostructure Evolution at Different Tailpipe Positions of a Dedicated Hybrid Engine2023-01-700310/30/2023
Hybrid vehicles, compared to pure fossil fuel vehicles, have added power battery pack, high-power electric motors. The space of the aftertreatment is limited, so the layout position of the aftertreatment system must be optimized. Meanwhile, the European 7 emission standard reduces the particulate number (PN) limit particles size from 23nm to 10nm, presenting new challenges for the aftertreatment system. The focus of this study is to investigate the variations in particles size distribution and nanostructure of soot particles during the exhaust along a dedicated hybrid engine aftertreatment system (catalyst carrier free). Four operating conditions were selected for the test, namely 2000 r/min-0.2 MPa, 2000 r/min-0.8 MPa, 4500 r/min-0.2 MPa, and 4500 r/min-0.8 MPa. The particles sampling points are before Three-way catalyst (TWC), after TWC, and after gasoline particulate filter (GPF). Engine Exhaust Particle Sizer (EEPS) was used to analyze the changes in particle modal distribution
Fu, Jiale, Hu, Zhiyuan, Fang, Liang, Lou, Diming, Tan, Piqiang, Yin, Qi
Tubing Coated with Light-Powered Catalysts Aids Drug ManufacturingTBMG-4694811/01/2022
Efficiencies greater than 55% are experimentally demonstrated using an oxygen-enriched oxidizer in a six stroke engine2022-01-050903/29/2022
Criteria emissions (CO, Pb, NOx, UHC, PM, and SOx) from internal combustion engines have been greatly reduced since the 1970s; however, the greenhouse gas CO2 emissions have remained substantial. CO2 emissions are demonstrated to be significantly reduced through improved thermal efficiency. Improved thermal efficiency has been achieved experimentally through using an oxygen-enriched oxidizer, a six stroke engine cycle, enhanced radical formation, heat recovery and recycle, lean combustion, and high levels of exhaust gas recirculation. Thermal efficiencies greater than 55% are demonstrated. This technology is able to reduce the greenhouse gas emissions from a vehicle by greater than 24% mass of carbon dioxide per distance traveled. According to Statistica.com, the average new car sold in the EU in 2019 emitted 122 grams of CO2 per kilometer. These emissions could be reduced to less than 93 grams of CO2 per kilometer using this technology. Savings in fuel consumed are considerable and
Jung, Philip Owen
OSC modelling of 3-way automotive catalysts to understand the effect of latent OSC on dynamic OSC performance2022-01-069303/29/2022
A Three-way automotive catalyst's ability to store oxygen is still a crucial performance metric for modern day catalyst applications. With more stringent emissions legalisation, the oxygen storage capacity (OSC) within the catalyst can assist with converting different exhaust gases such as CO, THC and NOx under transient operating conditions. OSC is currently the only onboard catalyst performance metric recorded during a vehicle's useful life. Catalyst performance is correlated to this OSC measurement. OSC in 3-way automotive catalysts can be split into two main OSC types. "Latent OSC" deep within the layers of the washcoat and "dynamic" OSC on the surface layers of the catalyst washcoat. Dynamic OSC is more commonly applied in the evaluation of the activity of the catalyst during practical operation. This paper uses a kinetic OSC model with a layered washcoat approach to analyse OSC test data and show how latent OSC can affect the dynamic OSC performance of a 3-way catalyst. Model
Mc Grane, Liam, Douglas, Roy, Elliott, Matthew, Irwin, Kurtis, Woods, Andrew, Pedlow, Andrew
Mean-value exergy modeling of internal combustion engines: sensitivity analysis2022-01-043103/29/2022
This work proposes the application of the mean-value exergy-based internal combustion engine model, recently developed by the authors, for the quantification of the exergy transfer and destruction phenomena over different driving conditions. A thorough sensitivity analysis with respect to different driving cycles, environmental temperatures, and exhaust gas recirculation rates is performed. This allows to assess how driving conditions and environment affect the exergetic behavior of the engine, providing insights on the availability transfer and destruction phenomena and, ultimately, inefficiency.
Pozzato, Gabriele, Rizzo, Denise, Onori, Simona
Development of ceramic EHC2022-01-065103/29/2022
In recent years, electrically heated catalysts (EHCs) have been developed to reduce emissions. Among several types of heating methods of EHCs, the direct heating method, in which a current is applied to the catalyst substrate directly, makes it easy to activate the catalyst before starting the engine. The research results that emissions (HC + NOx) were reduced 76% with the direct heating EHC have been reported. In terms of catalyst support, ceramics are considered to be a better material for the substrate than metal due to the coefficient of linear thermal expansion difference between the wash coat and the substrate. However, EHCs made of ceramics have issues such as controllability of the current distribution and durability reliability of the connection between the substrate and the electrodes. This paper reports about the hardware configuration of the direct heating EHC made of ceramics, including the catalytic substrate as an electric circuit, its electrode, and the insulation
Sadamitsu, Takahiro, Oki, Toshinori, Korenaga, Shingo, Hirooka, Shigemasa, Iwasaki, Shingo, Iida, Tatsuo
Deceleration Cylinder Cutoff Emission Control Strategy for Ammonia Reduction in Spark Ignition Engines2022-01-064903/29/2022
The newly-proposed Euro 7 emission standard has added regulation of ammonia emission for gasoline vehicles. This paper proposes a new emissions-control strategy to satisfy the regulated ammonia emissions levels. The control strategy utilizes deceleration cylinder cut-off (DCCO) to reduce/eliminate deceleration fuel cutoff (DFCO), reducing exhaust rich-lean air fuel ratio (A/F) variations and allowing tight management of exhaust three-way catalyst oxygen, which reduces CO/NOx ratio and NH3 formation rate inside catalytic converter. This results in more than 80% of ammonia emission reduction on the WLTP drive cycle without negative impact on all other regulated emissions.
luo, Xi, Yang, Xiaojian, Wilcutts, Mark, Ortiz-Soto, Elliott
Novel Pt/Rh coated gasoline particle filter development and its application2022-01-066103/29/2022
With the stringent China6 legislation implementation in 2020, Gasoline Particular Filters (GPF) are widely applied to control Particle Number (PN), THC, CO, and NOx emissions from gasoline engines. The typical GPF product in the market is usually coated with a Pd/Rh three-way catalyst (TWC). In this work, a novel and cost-effective GPF was achieved through Pd substitution with lower cost Pt in a novel Pt/Rh TWC coating. The Pt/Rh GPF was evaluated for back pressure (BP) under clean and soot loaded conditions, PN Filtration efficiency, TWC activity, and soot regeneration. The aged Pt/Rh GPF gave superior TWC performance.
Qiao, Dongsheng, Pan, Xinbo, He, Jun, Chen, Jiahao, Ji, Hongyu, Andersen, Paul
Efficiencies greater than 55% are experimentally demonstrated using oxygen-enriched oxidizer in a six stroke engine2022-01-051503/29/2022
Criteria emissions (CO, Pb, NOx, UHC, PM, and SOx) from internal combustion engines have been greatly reduced since the 1970s; however, the greenhouse gas CO2 emissions have remained substantial. CO2 emissions are demonstrated to be significantly reduced through improved thermal efficiency. Improved thermal efficiency has been achieved experimentally through using an oxygen-enriched oxidizer, a six stroke engine cycle, enhanced radical formation, heat recovery and recycle, lean combustion, and high levels of exhaust gas recirculation. Thermal efficiencies greater than 55% are demonstrated. This technology is able to reduce the greenhouse gas emissions from a vehicle by greater than 24% mass of carbon dioxide per distance traveled. According to Statistica.com, the average new car sold in the EU in 2019 emitted 122 grams of CO2 per kilometer. These emissions could be reduced to less than 93 grams of CO2 per kilometer using this technology. Savings in fuel consumed are considerable and
Jung, Philip Owen
Performance optimization using ANN-SA approach for VVA system in diesel engine2022-01-075903/29/2022
Diesel engine is vital in the industry for its characteristics of low fuel consumption, high-torque, reliability, and durability. Existing diesel engine technology has reached the upper limit. It is difficult to break through the fuel consumption and emission of diesel engines. VVA (Variable Valve system) is a new technology in the field of the diesel engines. In this paper, GT-Suite and ANN (artificial neural network) model are established based on engine experimental data and DoE simulation results. By inputting Intake Valve Opening crake angle (IVO), Intake Valve Angle Multiplier (IVAM) and Exhaust Valve Angle Multiplier (EVAM) into the ANN Model, and by using SA (simulated annealing algorithm), the optimized results of intake and exhaust valve lift under the target conditions are obtained. According to the optimized results, the fuel consumption of BSFC (brake specific fuel consumption) can be saved by 3.9%, 0.9%, and 7.3% at three different target working conditions, respectively
Lou, Diming, Tang, Yuanzhi, Zhao, Yinghua, Fang, Liang, Tan, Piqiang, Hu, Zhiyuan, Han, Jie, Song, Xiaojun
Extending NREL's FASTSim to model catalyst transient warmup behavior2022-01-057803/29/2022
A custom version of NREL's FASTSim was extended to include transient thermal models for engine and catalysts with the goal of understanding catalyst warmup dynamics during cold start for light duty vehicles representing a range of vehicle sizes, makes, and models, including a small sedan and multiple SUV or truck body types. The model was calibrated and separately validated for various each vehicle using dynamometer test data conducted over various regulatory drive cycles and a sweep of ambient and initial conditions ranging from -20°C to 40°C. The NSGA-II multi-objective-optimization algorithm in Python's PyMOO package was used to select calibration parameters to identify the Pareto minimal hyper-surface of time-weighted engine temperature, catalyst temperature, and fueling errors for each test data set. By scaling component parameters with respect to engine peak power, the model was then exercised over a nationally representative range of initial temperatures, ambient temperatures
Baker, Chad
Review of Vehicle Engine Efficiency and Emission Control Regulations and Technologies2022-01-065003/29/2022
This review covers some of the major advances pertaining to reducing tailpipe emissions of greenhouse gases and criteria pollutants. Discussed are both new and upcoming regulations, and technological advances for improving engines and after-treatment systems. We will also cover related aspects of alternative fuels, including electrification and renewable fuels. Both light- and heavy-duty vehicles are in scope. We cover the latest criteria pollutant tightening in Europe (Euro 7/VII) and the US - advanced clean cars 2.0 for light-duty and ultra-low NOx regulations for heavy-duty vehicles in California. We also cover the implications of the proposed revisions to the CO2 targets along with the electrification targets in these markets. We will highlight the major improvements in engine efficiency, after-treatment systems and also individual technologies (filters, SCR, TWC, etc.) to meet these regulations.
Joshi, Ameya
An investigation of bio/synthetic fuel blends on a multi-cylinder compression ignition engine2022-01-053103/29/2022
Oxygenated, low energy-density fuels have the potential to reduce engine-out NOx and soot emissions. Additionally, synthetic fuels can provide a pathway to reach carbon neutral utilization of hydrocarbon-based fuels in IC engines. Oxymethylene dimethyl ether (OME) is one such synthetic, low energy density fuel, derived from sustainable sources that in combination with conventional fossil fuels with higher energy content, has the potential to reduce NOx emissions below the US and EU VI legislative limits while maintaining ultra-low soot and CO2 emissions. The objective of this work is to investigate and compare the performance, emissions and efficiency of a modern multi-cylinder diesel engine under conventional high temperature combustion (HTC) with 3 different fuels; 1) 10% OME fuel, blended with conventional ultra-low sulphur diesel (OME10), 2) EU bio-diesel, made from vegetable oils with 10% renewable energy source (RES) content (EU B10), and conventional diesel in North America (B0
Asad, Usman, Ramos, Manuel, Tjong, Jimi
Effect of EGR Coupled SCR on NOx Emission Characteristics of Heavy-Duty Diesel Engine2022-01-066403/29/2022
EGR and SCR has become an important technology to reduce NOx emission of heavy-duty diesel engine and meet increasingly stringent emission regulations. This paper studied on the effect of EGR coupled SCR on NOx emission characteristics of heavy-duty diesel engine based on engine bench test. The results showed that the NO emission reduction performance of EGR coupled SCR increased with the increase of engine load, and the increase slowed down after 75% load. EGR coupled SCR has little effect on NO2 emission reduction, the increase of engine speed can significantly improve the efficiency of NO2 emission reduction at 75% and 100% load. The effect of EGR coupled SCR on reducing NO became more and more significant with the increase of diesel engine load, but the effect was no longer significant when the reduction of NO emission exceeded a certain limit under the same working condition. EGR had better NOx reduction performance at 50% load of diesel engine when the valve opening was 25% and
Lou, Diming, Kang, Lulu, Tan, Piqiang, Hu, Zhiyuan, Zhang, yunhua, Fang, Liang
Pre-Heating the Aftertreatment System with a Burner2022-01-067103/29/2022
NOx emissions limits for commercial trucks will be drastically reduced in the United States and Europe later in this decade. European regulators have proposed that pre-heating of the aftertreatment system with a diesel burner may be needed to meet their new limit, particularly if the engine is not equipped with exhaust gas recirculation to reduce engine-out NOx. This study considered a burner installed between a 13L engine and an appropriately-sized in-line DOC/DPF/SCR aftertreatment system. Initially, a wide range of burner and air pump operating conditions were examined to determine the maximum fueling rate and corresponding air flow rate necessary to complete combustion and to convey the resultant heat downstream to the aftertreatment components. From this survey, an optimal realistic operating condition for pre-heating emerged. This condition was then applied for various periods of time before the engine was started in order to run various regulatory cycles, including the cold- and
Harris, Thomas, Bellard, Raphael, Muhleck, Matthew, Palmer, Guenter
On the utility of ammonia sensors for diesel emissions control2022-01-066303/29/2022
Ammonia sensors enjoyed a brief window of series production in North America, but have since largely been ignored as a component to control diesel exhaust emissions. Presumably this happened due to their unfavorable statibility properties and improvements in NOx sensor hardware and signal processing. With ever- increasing pressure on tail pipe NOx standards and a possible European OBM regulation requiring reporting of tailpipe ammonia emissions, there is renewed interest in the ammonia sensor for series production. We present a set of use-cases where the ammonia sensor is again expected to provide a benefit for tailpipe emissions, and run simulations and parametric studies to quantify the required accuracy specification for the sensor to be useful.
Van Nieuwstadt, Michiel
Optimized TWC for emission control on a heavy duty stoichiometric CNG engine2022-01-070603/29/2022
Compressed natural gas (CNG) engines have attracted increasing attention in the heavy duty (HD) vehicle market as an alternative to conventional diesel fuel often due to the abundance and low price of CNG. However, it is challenging to meet the increasingly stringent China VI legislation, particularly for hydrocarbons (mainly CH4), carbon monoxide (CO), nitrogen oxides (NOx) and ammonia (NH3). In this work, approaches were explored in which a gasoline three-way catalyst (TWC) was modified through the optimization of materials and design. The optimized TWC was evaluated in a laboratory reactor and with a HD stoichiometric CNG engine. Lab reactor results showed improve CH4 light off performance. Ammonia (NH3) is a by-product during the operation of three-way catalysts (TWC) on a stoichiometric CNG engine. Catalytic modifications are discussed which were demonstrated to reduce NH3 emissions due to the relatively low NH3 limit for China VI legislation. Data are reported demonstrating the
Qiao, Dongsheng, Wang PhD, Jingwen, Chuma, Hellen, Hu, Hao, Ji, Hongyu, Andersen, Paul, Xu, Shi, Li, Qin
EGR Cooler Fouling Reduction: A New Method for Assessment in Early Engine Development Phase2022-01-071003/29/2022
High pressure EGR provides NOx emission reduction even at low exhaust temperatures. To maintain a safe EGR system operation over a required lifetime, the EGR cooler fouling must not exceed an allowable level, even if the engine is operated under worst case conditions. A reliable fouling simulation model represents a valuable tool in the engine development process, which validates operating and calibration strategies regarding fouling tendency, helping to avoid fouling issues in a late development phase close to series production. Long-chained hydrocarbons in the exhaust gas essentially impact the fouling layer formation. Therefore a simulation model requires reliable input data especially regarding mass flow of long-chained hydrocarbons transported into the cooler. There is a huge number of different hydrocarbon species in the exhaust gas, but their individual concentration typically is very low, close to the detection limit of standard in-situ measurement equipment like GC-MS
Liebsch, Stephan, Leesch, Mirko, Zumpf, Philipp, Jacob, Jörg, Mehnert, Ronny, Martin, Peter, Kneisel, Max
Real World Emissions Analysis Using Sensor-based Emissions Measurement System for Light-duty Direct-Injection Gasoline Vehicle2022-01-068603/29/2022
In recent years, particulate matter (PM) emitted from direct-injection gasoline vehicles has become a problem. In addition, it is often reported that ammonia (NH3) is emitted from gasoline vehicles equipped with a three-way catalyst. These emissions might be largely emitted especially when driving in on-road driving conditions. In this study, we investigated the emissions, NOx, NH3, and PM / PN (particulate number) of a light-duty direct-injection gasoline vehicle when driving on actual roads. Using a small direct-injection gasoline vehicle equipped with a three-way catalyst, we ran nine times on the same route and measured these emissions. Based on these measurements, we analyzed "where" and "how much" NOx, NH3, and PM / PN were emitted. As a result, it was clarified that a large amount of NOx is emitted after the fuel is cut during deceleration, NH3 is emitted when the air-fuel ratio becomes rich, and PM / PN is emitted during rapid acceleration of the vehicle. Then, the relationship
Eang, Chanpaya, Sato, Susumu, Tanaka, Kotaro, Tange, Takeshi, Chen, Jiaxin
Assessing the effect of torque converter losses on the start emission and Engine stability in TGDI AT Vehicle2021-28-018510/01/2021
The emission norms around the world are continuously changing and getting stringent with every revision. India is on its way to make its emission norms at par with that prevailing in the developed nations. The cold-start condition is an important factor affecting vehicle emissions from gasoline direct injection (GDI) and port fuel injection (PFI) engines. In this paper, the effects of change in torque converter losses on emissions are experimentally investigated in a TGDI AT vehicle. The instant engagement of the torque converter puts a sudden torque on the engine and thus affects its stability. Thus, to overcome the stability issue, Engine torque has to be simultaneously increased for smooth engagement. As a result, the likelihood of the slightly leaner air-fuel mixture in the cylinder, which results in higher Nox formation, is much greater in an AT vehicle than that of a similar MT vehicle. Additionally, the temporary ineffectiveness of motor vehicle emission controls at startup
RAI, ABHISHEK, SARAN KUMAR REDDY, KETHIREDDY, SOMANI, KAPIL
Design and Lay-out optimization challenges and solutions to Develop Open Crankcase Ventilation for family of Automotive Diesel Engines to meet stringent emission norms (Euro-VI) and reduced Oil-consumptions2021-26-018809/22/2021
For more than 3 decades, every automotive industry is focusing on continuous development of emission control technologies and suitable strategies. It was mainly driven by the legislation to improve or protect the environmental air quality for healthy life. Though the exhaust emission from an IC engine of an automobile is the primary and main source of pollutants, the other source such as Crankcase is also becoming a concern in recent years, while the norms becoming stringent. Hence, there is a need of regulating crankcase emissions. In a reciprocation motion of piston in an IC engine, the gases that leak past the piston rings from the combustion chamber and contain soot, particulate matter, water and oil vapor, unburned fuel and exhaust by product gases (CO, CO2, NOx, etc.) and aerosol generated from lubrication oil the entire mixture is called “blow by” gases. Crankcase emissions are bit complex mixture of combustion products and aerosol to be treated. In detail, the Crankcase
Jayagopal, S., Mahesh.Bharathi, R, Sadagopan, Krishnan, Mahesh, P, M, Sathyanandan, Bolar, Yogesh, Grasius, Deepu
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