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Training / Education

Fuel Cells for Transportation

2022-09-01
This is a three-day course which provides a comprehensive and up to date introduction to fuel cells for use in automotive engineering applications. It is intended for engineers and particularly engineering managers who want to jump‐start their understanding of this emerging technology and to enable them to engage in its development. Following a brief description of fuel cells and how they work, how they integrate and add value, and how hydrogen is produced, stored and distributed, the course will provide the status of the technology from fundamentals through to practical implementation.
Training / Education

Electrochemical Energy Systems for Electrified Aircraft Propulsion Batteries and Fuel Cell Systems

2022-05-04
In this joint AIAA / SAE course, participants will learn about Electro-chemical Energy Systems (EES), with an emphasis on electrified aircraft propulsion and power applications. The course will present the fundamentals in chemistry, materials science, electrical, and mechanical engineering for various EESs including high voltage battery systems (Li-ion and beyond) and fuel cells (PEM, solid oxide fuel cells, and others).
Technical Paper

A Perspective on Materials Selection for Body Structure Lightweighting in Battery Electric Vehicles

2022-03-29
2022-01-0233
The secular trend of automotive body structure light-weighting for internal combustion engine (ICE) vehicles is constrained by simultaneous and increasingly challenging vehicle cost, fuel economy and passenger safety standards. Mass optimization via materials selection in ICE vehicles, therefore, is ultimately dependent on the normalized cost of mass reduction solutions and the associated implications on passenger safety and vehicle performance metrics. These constraints have resulted in development and implementation of increasingly high specific-strength solutions for metallic components in the body structure and chassis. In contrast, mass optimization in battery electric vehicles is subject to alternative performance metrics to fuel efficiency, although considerations for vehicle safety and cost naturally remain directionally similar.
Technical Paper

Design and Optimization of an Electric Car Chassis and Body using Structural Analysis and CFD

2022-03-29
2022-01-0292
The transition from traditional gasoline-powered automobiles to electric vehicles (EVs) has taken time, two major challenges of engine- powered vehicles are greenhouse gas emissions and fuel economy. Electric cars require less maintenance. A lot of money can be saved while also helping the environment. In today's world, working with lightweight materials have emerged as a key area for improvement in the automotive industry. The most efficient method for increasing power output is to reduce the weight of vehicle components. Composite materials have benefited greatly from research and development because they are stronger, more recyclable, and easier to integrate into vehicles. The primary goal of this research is to design the body and chassis frame of a two-seater electric car.
Technical Paper

Numerical Assessment of Tribological Performance of Different Llow Viscosity Engine Oils in a 4-Stroke CI Light-Duty ICE

2022-03-29
2022-01-0321
Decreasing fuel consumption in Internal Combustion Engines (ICE) is a key target for engine developers in order to achieve the CO2 emissions limits during a standard cycle. In this context, reduction of engine friction can help meet those targets. The use of Low Viscosity Engine Oils (LVEOs), which is currently one of the avenues to achieve such reductions, is studied in this manuscript through a validated numerical simulation model that predicts the friction of the engine’s piston-cylinder unit, journal bearings and camshaft. These frictional power losses are obtained for four different lubricant formulations which differ in their viscosity grades and design. Results show a maximum friction savings of up to 6% depending on the engine operating condition, where the major reductions come from hydrodynamic-dominated components such as journal bearings, despite an increase in friction in boundary-dominated components such as the piston-ring assembly.
Technical Paper

Gasoline Direct Injector Deposits: Impacts of Fouling Mechanism on Composition and Performance

2022-03-29
2022-01-0488
Gasoline Direct-Injection Spark-Ignition (DISI) injector performance is a key focus in the automotive industry as the vehicle parc transitions from Port Fuel Injected (PFI) to DISI engine technology. DISI injector deposits, which may impact the fuel delivery process in the engine, seem to accumulate over longer time periods and greater vehicle mileages than traditional combustion chamber deposits (CCD). These higher mileages and longer timeframes make the evaluation of these deposits in a laboratory setting more challenging due to the extended test durations necessary. The need to generate injector tip deposits for research purposes begs the questions, can an artificial fouling agent to speed deposit accumulation be used, and does this result in deposits similar to those formed naturally? Field testing was used to develop high-mileage injectors from DISI vehicles.
Technical Paper

A New Pathway for Prediction of Gasoline Sprays using Machine-Learning Algorithms

2022-03-29
2022-01-0492
The fuel spray process is of utmost importance to internal combustion engine design as it determines engine performance and emissions characteristics. While designers rely on CFD for understanding of the air-fuel mixing process, there are recognized shortcomings in current CFD spray predictions, particularly under super-critical or flash-boiling conditions. In contrast, time-resolved optical spray experiments have now produced datasets for the three-dimensional liquid distribution for a wide range of operating conditions and fuels. Utilizing these detailed experimental results, we have explored a machine learning approach to prediction of fuel sprays. The ML approach for spray prediction is promising because (1) it does not require phenomenological spray models, (2) it can provide time-resolved spray data without time-stepping simulation, and (3) it is computationally faster than CFD. In this study, a pixel-regression model has been developed and applied for gasoline spray prediction.
Technical Paper

Laser-Based In-Exhaust Gas Sensor for On-Road Vehicles

2022-03-29
2022-01-0535
Indrio Technologies has developed a novel on-board sensor, named Ignis, for detecting oxides of nitrogen (NOx) and ammonia (NH3) in diesel exhaust streams with sensitivities and molecular specificity unmet by existing technologies. This is a key technological need for diesel engine manufacturers, who face difficulty in precisely controlling their exhaust aftertreatment systems due to the lack of widely deployable sensors capable of differentiating between NOx, NH3 and other species in the exhaust stream. The successful incorporation of the proposed sensor can result in greater fuel efficiency improvements while matching new stringent 2027 California and 2030 EPA NOx emissions standards. Once the product has reached deep market penetration, the fleet-wide fuel economy improvements and NOx emissions reductions enabled by this product will lead to reduced carbon emissions and healthier air with lower amounts of NOx-induced smog, ground-level ozone, and acid rain.
Technical Paper

Fast Air-Path Modeling for Stiff Components

2022-03-29
2022-01-0410
Development of powertrain control systems frequently involves large-scale transient simulations, e.g. Monte Carlo simulations or drive-cycle optimizations, which require fast dynamic plant models. Models of the air-path—for internal combustion engines or fuel cells—can exhibit stiff behavior, though, causing slow numerical simulations due to either using an implicit solver or sampling much faster than the bandwidth of interest to maintain stability. This paper proposes a method to reduce air-path model stiffness by adding an impedance in series with potentially stiff components, e.g. throttles, valves, compressors, and turbines, thereby allowing the use of a fast-explicit solver. An impedance, by electrical analogy, is a frequency-dependent resistance to flow, which is used to suppress the high-frequency dynamics causing air-path stiffness, while maintaining model accuracy in the bandwidth of interest.
Technical Paper

A Review of Current Understanding of the Underlying Physics Governing the Interaction, Ignition and Combustion Dynamics of Multiple-injections in Diesel Engines

2022-03-29
2022-01-0445
This work is intended to be a comprehensive technical review of existing literature and a synthesis of current understanding of the governing physics behind the interaction of multiple fuel injectio ns, ignition and combustion behavior of multiple-injections in diesel engines. Multiple-injection is a widely adopted operating strategy applied in modern compression-ignition engines, which involves various combinations of small pre-injections and post-injections of fuel before and after the main injection and splitting the main injection into multiple smaller injections. This strategy has been conclusively shown to improve fuel economy in diesel engines while achieving simultaneous NOx, soot, and combustion noise reduction in addition to a reduction in the emissions of unburned hydrocarbons and CO by preventing fuel wetting and flame quenching at the piston wall.
Technical Paper

Development and validation of an EHN mechanism for fundamental and applied chemistry studies

2022-03-29
2022-01-0455
Autoignition enhancing additives have been used for years to enhance the ignition quality of diesel fuel, with 2-ethylexyl nitrate (EHN) being the most common additive. EHN also enhances the autoignition reactivity of gasoline, which has advantages for some low-temperature combustion techniques, such as Sandia’s Low-Temperature Gasoline Combustion (LTGC) with Additive-Mixing Fuel Injection (AMFI). LTGC-AMFI is a new high-efficiency and low-emissions engine combustion process based on supplying a small, variable amount of EHN into the fuel for better engine operation and control. However, the mechanism by which EHN interacts with the fuel remains unclear. In this work, a chemical-kinetic mechanism for EHN was developed and implemented in a detailed mechanism for gasoline fuels. The combined mechanism was validated against shock-tube experiments with EHN-doped n-heptane and HCCI engine data for EHN-doped regular E10 gasoline. Simulations showed a very good match with experiments.
Technical Paper

Experimental Evaluation of Methane-Hydrogen Mixtures for Enabling Stable Lean Combustion in Spark-Ignition Engines for Automotive Applications

2022-03-29
2022-01-0471
Economy decarbonization will be one of the main goals for the following years. Research efforts are being focused on reducing carbon-based emissions, by increasing the efficiency of the transport power plants while developing new fuel production methods that reduce the environmental footprint of the refinement process. Consequently, the depletion of conventional fuels derived from petroleum with high carbon content, such as gasoline and diesel, motivated the development of propulsive alternatives for the automotive sector. In this paradigm, methane (CH4) fuel appears as a mid-term solution due to its low carbon content, if compared with traditional fuels, and the low CO2 emissions during its production from renewable sources. However, the intrinsic properties of methane compromise the combustion process, subsequently increasing the emission of CO2.
Technical Paper

Modeling of regeneration dynamics in gasoline particulate filters and sensitivity analysis of numerical solutions

2022-03-29
2022-01-0556
Gasoline Direct-Injection (GDI) engine technology improves vehicle fuel economy toward future targets and simultaneously decreases CO2 emissions. The main drawback of this technology is the increased emission of particulates (when compared to their indirect injection-based technology counterpart). Thus, aftertreatment devices such as Gasoline Particulate Filters (GPFs) are today considered the most promising and practically adoptable solution to limit PM/PN out of GDI exhaust. The particulate filter traps soot particles resulting from fuel combustion and prevents their release into the atmosphere. Soot oxidation (also known as regeneration) is required at regular intervals to clean the filter, maintain a consistent soot trapping efficiency, and avoid the formation of soot plugs in the GPF channel.
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