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Assessment of the Potential of Power to Gas Fuels for Replacement of Fossile Fuels in Switzerland

EMPA-Panayotis Dimopoulos Eggenschwiler, Florian Kiefer, Karin Schröter, Christian Bach
  • Technical Paper
  • 2020-37-0027
To be published on 2020-06-23 by SAE International in United States
In Switzerland, road traffic is responsible for one third of greenhouse gas emissions respectively 40% of the CO2 emissions and therefore accounts for the largest single share of all sectors. These emissions have even increased slightly since 1990 (from 15.5 to 16.2 million tCO2). Private individual road transport achieves a mileage of approximatively 91.0 billion pkm (person-kilometer) and 17.2 billion tkm (tons-kilometer) per year. Therefore, 3.3 billion liters of gasoline and 3.2 billion liters of diesel are used, resulting in 16.2 million tCO2 emissions in total. Thereof, 10.2 million tons of CO2 are emitted by passenger cars and 1.7 million tons by trucks, the two most important means of transport concerning CO2 emissions. The rest is produced by vans, buses, motorcycles, railways and shipping, national air traffic and fuel tourism. The passenger cars are the most relevant application in terms of CO2 emissions with a share of 63% of the road vehicle CO2 emissions. To comply with the 95 g/km target, low CO2 vehicles have to be introduced. In the following, the number of such…
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High Voltage Battery durability enhancement in electric mobility through 1D CAE

Tata Motors Ltd-Sambhaji Jaybhay, Kiran Kadam, Sangeet Kapoor
Tata Motors, Ltd.-Santosh Kumar Venu
  • Technical Paper
  • 2020-28-0013
To be published on 2020-04-30 by SAE International in United States
The public transport in India is gradually shifting towards electric mobility. Long range in electric mobility can be served with High voltage battery (HVB), but HVB can sustain for its designed life if it’s maintained within a specific operating temperature range. Appropriate battery thermal management through battery cooling system (BCS) is critical for vehicle range and battery durability This work focus on two aspects BCS sizing and coolant flow optimization in Electric bus. BCS modelling was done in 1D CAE by using KULI software from M/s Magna Steyr. The objective is to develop a model of battery cooling system in virtual environment to replicate the physical testing. Electric bus contain numerous battery packs and a complex piping in its cooling system. BCS sizing simulation was performed to keep the battery packs in operating temperature range. Iterations were carried out to maintain uniform flow at the battery packs as well as to sustain target coolant flow requirement in order to maintain thermal uniformity across the battery packs 1D simulation is vital when it comes to analyzing…
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Application of Phase Change Materials (PCM) for reducing cabin heat load

Tata Motors Ltd-Mayank Manoj Dubey, Suresh Tadigadapa, Abhijit DUBE, Ankit Shukla, Anurag Maurya, Y.S.Sarath Reddy
  • Technical Paper
  • 2020-28-0037
To be published on 2020-04-30 by SAE International in United States
In regions like Indian Subcontinent, Gulf or Saharan & Sub-Saharan Africa, where the sunshine is abundant almost all year round, air-conditioning is an important aspect of vehicles (passenger cars, buses etc). Higher heat means higher cooling demand which means bigger AC system which in turn. Now AC compressor is a parasitic load on the engine like other auxiliaries. Upcoming emission norms will result in more stringent constraints on the power that can be made available to auxiliaries by engine. Moreover, one of the most frequent customer complaint in JD Power rating survey results of passenger vehicles is "AC cooling not fast enough". Hence, the proposed idea suggests a way reduce the air conditioning power consumption, without compromising on the cool-down performance by eliminating the heat load source itself. The best way to beat the heat and reduce cabin heat load is the stop the heat build-up itself. The present paper explores one such mean of reducing cabin heat build-up by leveraging latent heat properties of phase change materials and thus improving the air condition performance.With…
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Numerical Investigations on Heat Transfer and Flow Characteristics of Climate Control Systems in Electric Vehicles

Pranav Vikas India Pvt Ltd-Vijayaraghavan S, Govindaraj D
Pranav Vikas India Pvt Ltd.-Mahendravarman Radha
  • Technical Paper
  • 2020-28-0010
To be published on 2020-04-30 by SAE International in United States
Earth's surface temperatures would increase from 2.90 C to 3.40 C by the year 2100 due to global warming, leads to conceivable calamitous effects on human livelihoods, livestock, ecosystems and biodiversity. Overall globally several policies were made to reduce the carbon dioxide emission and other greenhouse gases. The transportation sector is one of the prominent sources of carbon dioxide emissions. On account of the significant emissions caused by conventional buses, migrating to electric buses which have zero tailpipe emissions for public transport fleets is essential. Taken into consideration of the energy density of traction batteries, and cost, energy utilized for HVAC applications should be optimized. Heat transfer and flow characteristics in the condenser and the evaporator zone of climate control system for electric buses were numerically studied and compared with experimental results. Grid independence and turbulence studies were carried out to develop the CFD methodology for this analysis. Air velocity and temperature was measured at different locations in the climate control system to calculate the flow and thermal performance. Fluid flow and heat transfer characteristics…
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Formula SAE Data Acquisition and Detailed Analysis of a Lap

Georgia Southern University-Connor M. Ashford, Aniruddha Mitra
  • Technical Paper
  • 2020-01-0544
To be published on 2020-04-14 by SAE International in United States
Formula Society of Automotive Engineers (FSAE) International is a student design competition organized by SAE. The student design involves engineering and manufacturing a formula style racecar and evaluating its performance. Testing and validation of the vehicle is an integral part of the design and performance during the competition. At the collegiate level the drivers are at the amateur level. As a result, the human factor plays a significant role in the outcome of the dynamic events. In order to reduce the uncertainty factor and improve the general performance, driver training is necessary. Instead of overall performance of the driver based on individual lap, our current research focuses on the more detailed components of the driver’s actions throughout different sections of the lap. A complete lap consists of several components, such as, straight line acceleration and braking, max and min radius cornering, slalom or “S” movements, and bus stops or quick braking and turning. In order to evaluate the performance of each driver in each of these components, an AiM data acquisition system is mounted in…
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Hydrogen Fuel Cell Buses: Modelling and Analysing Suitability from an Operator and Environmental Perspective

Queen's University Belfast-Darryl Doyle, Andrew Harris, Steve Chege, Lucinda Douglas, Juliana Early
Wrightbus-Robert Best
  • Technical Paper
  • 2020-01-1172
To be published on 2020-04-14 by SAE International in United States
Global commitments to decrease greenhouse gas emissions have led to a shift to alternative powertrains in the transport sector. In addition to this, stricter controls on air quality within cities has seen the introduction of zero emission zones, requiring vehicles with full zero emission capabilities. As a result, there is growing interest in hydrogen fuel cell electric buses (FCEBs) as a zero local emission vehicle with superior range, operational flexibility and refuelling time than other clean alternatives e.g. battery electric buses (BEBs). This is illustrated in increased investment through projects such as JIVE/JIVE2, which are deploying nearly 300 FCEBs and refuelling infrastructure in Europe by the early 2020s. This paper details the performance and suitability analysis of a proposed FCEB, using a quasistatic backwards-facing Simulink powertrain model. The model is validated against existing vehicle data (Mk1), allowing it to be further leveraged for predictions of an advanced future production vehicle (Mk2) with next generation motors and fuel cell stack. The modelled outputs are used for a comparison of the FCEB performance to an equivalent BEB…
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Study of thermal efficiency improvement by multi-hole nozzle

Hino Motors Ltd.-Kazunori Yoshitomi, Yoshihiro Funayama, Mori Ishii, Hiroshi Nakajima
  • Technical Paper
  • 2020-01-0304
To be published on 2020-04-14 by SAE International in United States
A truck and bus transportation which support logistics and people, diesel engines are highly expected to have high thermal efficiency and low exhaust emissions over the next few decades. Effective methods to achieve even higher thermal efficiency are to reduce a cooling loss from combustion chamber wall. A multi-hole diesel injector has a significant impact on improving engine thermal efficiency by enhancing a combustion activity and reducing a cooling loss. In this study, two types of diesel injectors – 8-hole and 14-hole - with the same flow rate were tested under heavy-duty diesel engine condition. Heat release rate, energy balance and engine emissions were investigated using the single-cylinder engine with displacement of 1,478 cc. Furthermore, an optical engine was used to observe quantitative spray penetration and flame development from shadowgraph imaging and analyze flame temperature by a two-color method. The results of the single-cylinder engine showed that the 14-hole injector exhibited higher indicated thermal efficiency thanks to lower cooling loss than 8-hole results. However, we observed a slightly higher exhaust loss in the case of…
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Statistical Analysis of City Bus Driving Cycle Features for the Purpose of Multidimensional Driving Cycle Synthesis

University of Zagreb-Jakov Topić, Branimir Skugor, Josko Deur
  • Technical Paper
  • 2020-01-1288
To be published on 2020-04-14 by SAE International in United States
Driving cycles are typically defined as time profiles of vehicle velocity, and as such they reflect basic driving characteristics. They have a wide application from the perspective of both conventional and electric road vehicles, ranging from prediction of fuel/energy consumption (e.g. for certification purposes), estimation of greenhouse gas and pollutant emissions to selection of optimal vehicle powertrain configuration and design of its control strategy. In the case of electric vehicles, the driving cycles are also applied to determine effective vehicle range, battery life period, and charging management strategy. Nowadays, in most applications artificial certification driving cycles are used. As they do not represent realistic driving conditions, their application results in generally unreliable estimates and analyses. Therefore, recent research efforts have been directed towards development of statistically representative synthetic driving cycles derived from recorded GPS driving data. The state-of-the-art synthesis approach is based on Markov chains, typically including vehicle velocity and acceleration as Markov chain states. However, apart from the vehicle velocity and acceleration, a road slope and vehicle mass are also shown to significantly impact…
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A New Simulation Approach of Estimating the Real-World Vehicle Performance

University of Leeds-Jianbing Gao, Haibo Chen, Junyan Chen, Kaushali Dave
  • Technical Paper
  • 2020-01-0370
To be published on 2020-04-14 by SAE International in United States
Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation. The traffic conditions and vehicles parameters were the inputs for traffic simulation. Based on the outputs (speed profiles and elevations) of target vehicles in the traffic simulation, then the real-world performance of…
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Deep Learning-based Queue-aware Eco-Approach and Departure system for Plug-in Hybrid Electric Bus at signalized intersections: a simulation study

Oak Ridge National Laboratory-Zhiming Gao, Tim LaClair
University of California-Fei Ye, Peng Hao, Guoyuan Wu, Danial Esaid, Kanok Boriboonsomsin, Matthew Barth
  • Technical Paper
  • 2020-01-0584
To be published on 2020-04-14 by SAE International in United States
Eco-Approach and Departure (EAD) has been considered as a promising eco-driving strategy for vehicles traveling in an urban environment, where signal phase and timing (SPaT) and geometric intersection description (GID) information are well utilized to guide the vehicles passing through the intersection in a most energy efficient manner. Previous studies by the authors formulated the optimal trajectory planning problem as finding the shortest path on a graph model where the nodes define the reachable states of the host vehicle (e.g., speed, location) at each time step, the links govern the state reachability from previous time step, and the link costs represent the energy consumption rate due to state transition. This method is effective in energy saving, but its computation efficiency can be enhanced by machine learning techniques. In this paper, we propose an innovative Deep Learning-based Queue-aware Eco-Approach and Departure (DLQ-EAD) System for a Plug-in Hybrid Electric Bus (PHEB), to provide an online optimal vehicle trajectory considering both the downstream traffic conditions (i.e. traffic lights, queues) and vehicle powertrain efficiency. Based on the optimal solutions…