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Simulation of Driving Cycles by Means of a Co-Simulation Framework for the Prediction of IC Engine Tailpipe Emissions

Exothermia SA-Vasileios Tziolas, Nikolaos Zingopis
Politecnico di Milano-Gianluca Montenegro, Angelo Onorati, Gianluca D'Errico, Tarcisio Cerri, Andrea Marinoni
  • Technical Paper
  • 2020-37-0011
To be published on 2020-06-23 by SAE International in United States
The current European legislation concerning pollutant emissions from IC engine vehicles is very stringent and demanding. In addition, the CO2 fleet emission must obey to a significant reduction path during the next decade, to cope with the prescribed targets recently agreed. The prediction of pollutant emissions from IC engines has been a challenge since the introduction of the emission regulation legislation. During the last decade, along with the more tightening limits and increased public concern about air quality, the capability of simulating different operating conditions and driving cycles with an acceptable computational effort has become a key feature for modern simulation codes. The role of 1D thermo-fluid dynamic simulation models is extremely important to achieve this task, in order to investigate the performances of the next generation of IC engines working over a wide range of operating conditions, under steady-state and transient conditions. This work is based on the idea of integrating two different 1D simulation tools in a co-simulation environment, realizing a strict numerical coupling between the two codes. The main goal is to…
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Unsettled Issues Concerning the Use of Fuel Cells in Electric Ground Vehicles

H2SG Energy Pte Ltd.-Bart Kolodziejczyk
  • Research Report
  • EPR2020002
To be published on 2020-05-13 by SAE International in United States
Lately, the idea of using hydrogen in automotive applications is gaining significant momentum. However, the concept of using clean hydrogen fuel generated from water via electrolysis is nothing new. Because of numerous challenges, previously hydrogen has never managed to become a mainstream industrial or automotive fuel. A decade ago, an attempt to introduce hydrogen for mobility failed miserably and for good reasons. Back then, the fuelcell technology, which efficiently converts hydrogen and atmospheric oxygen into electricity, was not as advanced as it is today. In addition, the fuel cell prototypes were bulky and expensive. After the first failed wave of hydrogen-based economy implementation followed by another ten years of development, hydrogen is back, and it seems that this time it is here to stay. The decade of research allowed for improvements in materials, components, and performance of entire fuel cell systems. In addition, new manufacturing tools and techniques have been developed to reduce system costs. Today’s fuel cell systems use a fraction of platinum catalysts compared to fuel cells ten years ago, yet their performance…
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Innovative Rear Air Blower Design Application for Improving Cabin Thermal Comfort with improved Air Distribution and Air Quality.

Subros Ltd-Ravi Garg, Suraj maske, Yogendra Singh Kushwah
  • Technical Paper
  • 2020-28-0034
To be published on 2020-04-30 by SAE International in United States
In recent times, overall thermal comfort and air quality requirement have increased for vehicle cabin by multifold. To achieve increased thermal comfort requirements, multiple design innovation has happened to improve HVAC performance. Most of the advance and add on features like Multizone HVAC, dedicated rear HVAC, Automatic climate control, Advance Air filters, and Ionizers etc lead to increase in cost, power consumption, weight, and integration issues. Besides this in the vehicle with only front HVAC, airflow is not enough to meet rear side comfort for many cars in the B/C/SUV segment. This study aims to analyze the various parameters responsible for human thermal comfort inside a car with the focus on lightweight, low power consumption, compact Rear Blower to make passengers more comfortable by providing optimum airflow inline of mean radiant temperatures and cabin air temperature. The new design of Rear blower external surfaces has a set of air modifier surfaces in the direction of flow outlet. The second set of air modifier surfaces & an air deflator portion provided just upstream of outlet portion.…
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Challenges to incorporate cabin air quality enhancer in mobility solutions

Tata Motors Ltd-Sambhaji Jaybhay, Balkrishna Gavhane, Sangeet Kapoor
Tata Motors, Ltd.-Shubham Vijay Nimsatkar
  • Technical Paper
  • 2020-28-0016
To be published on 2020-04-30 by SAE International in United States
In the past five years, Indian cities have been consistently appearing in the list of top 15 world’s most polluted cities. A common man in India, daily spend more than 2 hours on the road during commute to work, thus exposed to inhale highly polluted air. In case of passenger car users, he/she is exposed to ~ 6 times more polluted air compared to ambient air – as vehicle cabin is a closed space where the air recirculates through air conditioning (AC). Prolonged exposure to such polluted air shows increasing trend in respiratory illnesses, breathing discomfort and fatigue. This paper discusses about the key challenges involved in incorporating cabin air quality enhancer (cabin air filters) in mobility solution. Engineering challenges are packaging of cabin air filters in current vehicle cabin and its validation through objective assessment and subjective assessment by trained evaluator. The objective assessment comprises of bench tests and subjective assessment requires trained expert noses, hence it is a business of high development expense. Ultimately, this development cost will be borne by customer through…
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How well can mPEMS measure gas phase motor vehicle exhaust emissions?

Ford Motor Company-Diep Vu, Joseph Szente, Michael Loos, Matti Maricq
  • Technical Paper
  • 2020-01-0369
To be published on 2020-04-14 by SAE International in United States
“Real world emissions” is an emerging area of focus in motor vehicle related air quality. These emissions are commonly recorded using portable emissions measurement systems (PEMS) designed for regulatory application, which are large, complex and costly. Miniature PEMS (mPEMS) is a developing technology that can significantly simplify on-board emissions measurement and potentially promote widespread use. Whereas full PEMS use analyzers to record NOx, CO, and HCs similar to those in emissions laboratories, mPEMS tend to use electrochemical sensors and compact spectroscopic detectors for their small size and low cost. The present work evaluates this approach by comparing measurements of NOx, CO, CO2 and HC emissions from five commercial mPEMS to both laboratory and full regulatory PEMS measurements. It further examines the use of vehicle on-board diagnostics data to calculate exhaust flow, as an alternative to on-vehicle exhaust flow measurement. The evaluations include two vehicle types, gasoline direct injection and diesel, and employ the US EPA and Worldwide Harmonized Light duty drive cycles. The results show that two classes of electrochemical NOx sensors are capable of…
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Evaluating the Performance of a Conventional and Hybrid Bus operating on Diesel and B20 Fuel for Emissions and Fuel Economy

US Environmental Protection Agency-Matthew Brusstar, Scott Ludlam
University of Michigan-Rinav Pillai, Andre Boehman
  • Technical Paper
  • 2020-01-1351
To be published on 2020-04-14 by SAE International in United States
With ongoing concerns about the elevated levels of ambient air pollution in urban areas and the contribution from heavy-duty diesel vehicles, hybrid electric buses are considered as a potential solution as they are perceived to be less polluting and more fuel-efficient than their conventional engine counterparts. However, recent studies have shown that real-world emissions may be substantially higher than those measured in the laboratory, mainly due to operating conditions that are not fully accounted for in dynamometer test cycles. At the U.S. EPA National Fuel and Vehicle Emissions Laboratory (NVFEL), the in-use criteria emissions and energy efficiency of heavy-duty class 8 vehicles (up to 80,000 lbs) may be evaluated under controlled conditions in the heavy-duty chassis dynamometer test. The present study evaluated the performance of a conventional bus and hybrid bus for emissions and fuel economy under representative test cycles (including cold start and hot start conditions) with Diesel (#2) and Biodiesel (B20) fuel. The conventional bus was equipped with a Cummins ISL 8.3L engine and a Diesel Particulate Filter (DPF) and Diesel Oxidation Catalyst…
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A Control System for Maintaining Passenger Cabin Air Quality

Chulalongkorn University-Thanin Wangsawangkul, Thiti Maneepipat, Nattapong Sukumdhanakul, Porpin Pungetmongkol, Prabhath De Silva
DENSO International Thailand-Pradit Mahasaksiri
  • Technical Paper
  • 2020-01-1243
To be published on 2020-04-14 by SAE International in United States
This paper presents a control methodology to maintain vehicle cabin air quality within desirable levels, giving particular attention to gaseous contaminants carbon dioxide (CO2) and carbon monoxide (CO). The CO2 is generated by the occupant exhalation while the CO is assumed to be ingested with the incoming fresh air. The system is able to detect and improve cabin air quality by controlling the recirculation flap of the ventilation system to control the amount of fresh air intake. The methodology is demonstrated in the laboratory using controlled experiments with a production level automotive HVAC (Heating Ventilating and Air-Conditioning) module. The results indicated that the designed control system can work automatically and control the CO and CO2 gas concentrations within acceptable levels.
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Use of Partial Recirculation to Limit Build-Up of Cabin Carbon Dioxide Concentrations to Safe Limits per ASHRAE Standard-62

Calsonic Kansei North America Inc.-Gursaran Mathur
  • Technical Paper
  • 2020-01-1245
To be published on 2020-04-14 by SAE International in United States
Carbon dioxide exhaled by occupants remains within the cabin during operation of HVAC unit in recirculation mode. The CO2 inhaled by the occupants goes into their blood stream that negatively affects occupant’s health. ASHRAE Standard-62 (1999) specifies the safe levels of carbon dioxide in conditioned space for humans. The CO2 concentration limit per ASHRAE is 700 ppm over ambient conditions on a continuous basis. Based on the test data, at worst case scenario (idle condition where body leakage will be a minimal) results in CO2 concentrations of 1601, 2846, 4845 and 6587 ppm respective for 1 to 4 occupants in 30 minutes.Author has also conducted test by imposing ASHRAE standard-62. A controller was programmed for operating the blower unit’s intake door to go from recirculation to OSA mode when the measured carbon dioxide ppm level goes above 1100 ppm. The door stays in OSA mode until the cabin carbon dioxide falls to approximately 500ppm. By imposing these limits, the blower unit’s intake door cycles between 3 minutes to 6.5 minutes with four to one occupants…
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Real-world Emission Analysis Methods Using Sensor-based Emission Measurement System

Ibaraki University-Kotaro Tanaka
NGK Spark Plug Co., Ltd.-Takeshi Tange
  • Technical Paper
  • 2020-01-0381
To be published on 2020-04-14 by SAE International in United States
Every year, due to exhaust gas regulations that are getting stricter, the average air pollution is going to be solved, but the local roadside pollution is still pressing issue. In order to solve this local roadside pollution problem, it is necessary to evaluate and/or predict “where” and “how much” pollutants such as NOx are emitted. In recent years, Real Driving Emission regulations using PEMS (Portable Emission Measurement System) have been introduced mainly in Europe. However, PEMS has a configuration close to 100 kg, and its weight affects the driving conditions of vehicles running on actual roads. In this study, we focused on the analysis of real world emissions using SEMS (Sensor-based / Simple Emission Measurement System). Whereas PEMS is a method of sampling and analyzing exhaust gas, SEMS directly attaches NOx sensor and PM sensor to the exhaust pipe and measures the concentration. Although SEMS has a limited number of items that can be measured compared to PEMS, other analyzes are possible by devising the analysis method. This paper focuses on the analysis method of…
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Review of Vehicle Engine Efficiency and Emissions

Corning, Inc.-Ameya Joshi
  • Technical Paper
  • 2020-01-0352
To be published on 2020-04-14 by SAE International in United States
This review paper covers major regulatory and technology developments in 2019 pertinent to tailpipe emissions of greenhouse gases and criteria pollutants. Europe has proposed ambitious reductions in CO2 limits for both light- and heavy-duty sectors. The challenge is compounded with changing measurement norms and a significant shift away from fuel efficient diesels in the light-duty (LD) space. Both incremental and step changes are being made to advance internal combustion. New studies show that in-use NOx emissions from diesels can be much lower than required by the Euro 6 regulation. Discussions have already started on Euro 7 regulations, and the leading regulatory concepts and proposed technical solutions are provided. In the heavy-duty (HD) sector, the progress is outlined in improving engine and vehicle fuel efficiency through the US Department of Energy’s (DOE’s) SuperTruck II program and other representative studies. Common approaches among the participants include hybridization, waste heat recovery, and both open- and closed cycle incremental improvements. Emissions control focus is on evaluating pathways to achieve California’s contemplated low-NOx standards, recently also supported by the US…