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Unsettled Impacts of Integrating Automated Electric Vehicles into a Mobility-as-a-Service Ecosystem and Effects on Traditional Transportation and Ownership

International Transportation Innovation Center (ITIC)-Joachim Taiber
Tallinn University of Technology-Raivo Sell
  • Research Report
  • EPR2019004
Published 2019-12-20 by SAE International in United States
The current business model of the automotive industry is based on individual car ownership, yet new ridesharing companies such as Uber and Lyft are well capitalized to invest in large, commercially operated, on-demand mobility service vehicle fleets. Car manufacturers like Tesla want to incorporate personal car owners into part-time fleet operation by utilizing the company’s fleet service. These robotaxi fleets can be operated profitably when the technology works in a reliable manner and regulators allow driverless operation.Although Mobility-as-a-Service (MaaS) models of private and commercial vehicle fleets can complement public transportation models, they may contribute to lower public transportation ridership and thus higher subsidies per ride. This can lead to inefficiencies in the utilization of existing public transportation infrastructure. MaaS platforms can also cause a reduced reliance on parking infrastructure (e.g., street parking lanes and parking garages) which can contribute to an improvement in overall traffic flow, and a reduction in capital investment for commercial and residential real-estate development. Urban planning can be better centered around the true mobility needs of the citizens without sacrificing valuable…
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Unsettled Technology Domains in Robotics for Automation in Aerospace Manufacturing

Muelaner Engineering, Ltd.-Jody Muelaner
  • Research Report
  • EPR2019010
Published 2019-12-20 by SAE International in United States
Cost reduction and increasing production rates are driving automation of aerospace manufacturing. Articulated serial robots may replace bespoke gantry automation or human operations. Improved accuracy is key to enabling operations such as machining, additive manufacturing (AM), composite fabrication, drilling, automated program development, and inspection. New accuracy standards are needed to enable process-relevant comparisons between robotic systems.Accuracy can be improved through calibration of kinematic and joint stiffness parameters, joint output encoders, adaptive control that compensates for thermal expansion, and feedforward control that compensates for hysteresis and external loads. The impact of datuming could also be significantly reduced through modeling and optimization. Highly dynamic end effectors compensate high-frequency disturbances using inertial sensors and reaction masses. Global measurement feedback is a high-accuracy turnkey solution, but it is costly and has limited capability to compensate dynamic errors. Local measurement feedback is a mature, affordable, and highly accurate technology where the robot is required to position or align relative to some local feature. Locally clamped machine tools are an alternative approach that can utilize the flexibility of industrial robots while…
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On the Role of Nitric Oxide for the Knock-Mitigation Effectiveness of EGR in a DISI Engine Operated with Various Gasoline Fuels

SAE International Journal of Advances and Current Practices in Mobility

Sandia National Laboratories-Magnus Sjöberg, David Vuilleumier, Namho Kim
Toyota Motor Corporation-Nozomi Yokoo, Terutoshi Tomoda, Koichi Nakata
  • Journal Article
  • 2019-01-2150
Published 2019-12-19 by SAE International in United States
The knock-suppression effectiveness of exhaust-gas recirculation (EGR) can vary between implementations that take EGR gases after the three-way catalyst and those that use pre-catalyst EGR gases. A main difference between pre-and post-catalyst EGR gases is the level of trace species like NO, UHC, CO and H2. To quantify the role of NO, this experiment-based study employs NO-seeding in the intake tract for select combinations of fuel types and compression ratios, using simulated post-catalyst EGR gases as the diluent. The four investigated gasoline fuels share a common RON of 98, but vary in octane sensitivity and composition. To enable probing effects of near-zero NO levels, a skip-firing operating strategy is developed whereby the residual gases, which contain trace species like NO, are purged from the combustion chamber.Overall, the effects of NO-seeding on knock are consistent with the differences in knock limits for preand post-catalyst EGR gases. This suggests that for a majority of the conditions studied here, variations in NO concentration dominate the autoignition-influencing role of trace species that are present in pre-and post-catalyst EGR gases.…
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Characteristics of Flat-Wall Impinging Spray Flame and Its Heat Transfer under Diesel Engine-Like Condition: Effects of Injection Pressure, Nozzle Hole Diameter and Impingement Distance

SAE International Journal of Advances and Current Practices in Mobility

University of Hiroshima-Rizal Mahmud, Toru Kurisu, Onur Akgol, Keiya Nishida, Yoichi Ogata
  • Journal Article
  • 2019-01-2183
Published 2019-12-19 by SAE International in United States
Substantial amount of fuel energy input is lost by heat transfer through combustion chamber walls in the internal combustion engines. Thus, these heat losses account for reduced thermal efficiency, in that spray-wall impingement plays a crucial role in Direct Injection diesel engines. The objective of this study is to investigate the mechanism of the heat transfer from the spray/flame to the impinging wall under small diesel engine-like condition and how the spray characteristics are affected with regards to effect of injection pressure, nozzle hole diameter and impingement distance. The experiment results showed that injection pressure was predominant factor on spray-wall heat transfer.
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Understanding Base Oils and Lubricants for Electric Drivetrain Applications

Afton Chemical Corporation, Richmond, Virginia 23219, USA-Yungwan Kwak, Christopher Cleveland, Atanu Adhvaryu, Xinggao Fang
Afton Chemical Japan Corporation, Tokyo, Japan-Tsuneo Adachi
  • Technical Paper
  • 2019-01-2337
Published 2019-12-19 by SAE International in United States
The penetration of hybridization and electrification (HEV and EV) technology into automotive powertrain designs is an evolving trend resulting from global regulations intended to reduce transportation-related emissions of greenhouse gases and other pollutants and to improve vehicle fuel efficiency. In many HEV and EV hardware designs, drivetrain fluids have contact with the integrated electric motor (e-motor), which requires electrical and thermal properties to be considered in addition to traditional fluid properties.This paper discusses new insights gained around electrical and thermal properties of drivetrain fluids, with a specific emphasis on understanding the critical impacts of base oils (BOs). Electrical and thermal properties data as a function of temperature for a range of BOs as well as automatic transmission fluids are shared. We found that BOs and their viscosities play a critical role in cooling performance, while additives play a critical role in electrical conductivity (EC). That being said, we also have observed that additives in BOs can modify cooling performance. We will demonstrate how each component in the additive package affects EC and in some cases…
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Analysis on flow motion and combustion process in pre-chamber and main chamber for low-speed two-stroke dual-fuel engine

China Ship Power Institute Co. Ltd.-Teng Liu
Harbin Engineering University-Long Liu, Yue Wu, Qian Xiong
  • Technical Paper
  • 2019-01-2175
Published 2019-12-19 by SAE International in United States
Low-speed two-stroke dual-fuel engines has been paid more attention due to the energy efficiency design index and Tier III emissions limitations issued by International Marine Organization. Although the dual-fuel engines have strong merits on emissions reduction, which can reach the IMO Tier III without aftertreatment, the power output is much lower than that of diesel engines. Therefore, the dual-fuel engine is also needed to improve continuously. However, the mixing and combustion processes in the engine have not been fully understood. In this study, a 3D-CFD model of the dual-fuel engine was established using CONVERGE to explore the mixing and combustion processes. Locally embedding fine grids are considered at scavenging ports, natural gas injection ports, pre-chamber. The model was validated by experimental in-cylinder pressure. Then, the flow motion, mixing of natural gas and air, flow in pre-chamber, torch and combustion in main-chamber were analyzed based on swirl variation, flow velocity distribution, equivalence ratio distribution and torch propagation.
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CFD-Driven Preliminary Investigation of Ethanol-Diesel Diffusive Combustion in Heavy-Duty Engines

KTH Royal Institute of Technology-Nicola Giramondi, Mihai Mihaescu, Anders Christiansen Erlandsson
Scania CV AB-Anders Jäger
  • Technical Paper
  • 2019-01-2192
Published 2019-12-19 by SAE International in United States
The introduction of renewable alcohols as fuels for heavy-duty engines may play a relevant role for the reduction of the carbon footprint of the transport sector. The direct injection of ethanol as main fuel and diesel as pilot fuel in the engine combustion chamber through two separate injectors may allow good combustion controllability over the entire engine operating range by targeting diffusive combustion. Closed-cycle combustion simulations have been carried out using AVL FIRE coupled to AVL TABKIN for the implementation of the Flamelet Generated Manifold (FGM) chemistry reduction technique in order to investigate the influence of the injection system geometry and the injection strategy of pure ethanol and diesel fuel on ignition characteristics and combustion at different operating conditions.
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Three-dimensional simulations of oil dilution in DI diesel engines under motoring conditions with varying injection timing

Osaka Universty-Tsukasa Hori, Kohei Yamaji, Fumiteru Akamatsu
  • Technical Paper
  • 2019-01-2186
Published 2019-12-19 by SAE International in United States
This study presents a simulation method for oil dilution in diesel engines by a post injection to understand the oil dilution mechanism and to improve an empirical model predicting the evolution of oil dilution. To consider the wall film, two-dimensional governing equations are additionally solved along the cylinder wall. Primary critical Weber numbers are used to determine adhesion or a splash of droplets at wall impingements. Motoring engine simulations at different injection timings show that dilution ratios in simulations are in good agreements with those in experiments. Oil dilution is not proportional to injection timings in this motoring conditions.
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Wall Heat Transfer Modeling Based on the Energy Equation For Zero Dimensional Engine Simulation

Mazda Motor Corporation-Yuji Harada, Kenji Uchida, Hiroyuki Yamashita
  • Technical Paper
  • 2019-01-2313
Published 2019-12-19 by SAE International in United States
It was important for predicting wall heat flux to apply wall heat transfer model by taking into account of the behavior of turbulent kinetic energy and density change in wall boundary layer. Although energy equation base wall heat transfer model satisfied above requirements, local physical amounts such as turbulent kinetic energy in near wall region should be applied. In this study, in order to predict wall heat transfer by zero dimensional analysis, how to express wall heat transfer by using mean physical amounts in engine combustion chamber was considered by experimental and numerical approaches.
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Influence to the PN Emissions in Calibration Procedure for Portable and Stationary Solid Particle Number Measurement Systems

HORIBA Europe GmbH-Yoshinori Otsuki
HORIBA, Ltd.-Kenji Kondo, Kentaro Kojima, Takeshi Kusaka
  • Technical Paper
  • 2019-01-2196
Published 2019-12-19 by SAE International in United States
The Real Diving Emissions (RDE) regulation has been introduced since September, 2017 by utilizing the Portable Emissions Measurement System (PEMS). For the PEMS for the solid Particle Number (PN) measurement (PN-PEMS), the validation tests are required by comparing to the stationary PN measurement system on a chassis dynamometer prior to the on-road emissions testing. However, there are some cases that the emission results of PN-PEMS have big difference for that of the PMP system as the PN-PEMS does not have the same system configuration and calibration procedures as a PMP system. In this paper, the influence of the calibration procedure to the PN emissions results was observed by applying the calibration procedure of the PN-PEMS to the PMP system. The current systems configurations for PMP system and PN-PEMS, and the differences of them were described. And, the calibration procedure of the PN-PEMS was applied to the PMP system to adjust the system detection efficiency at 23 nm. Finally, the influence of the calibration protocol was investigated by compared the PN emissions of PMP system and…
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