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Internal short-circuit in cells/batteries is a phenomenon where there is direct electrical contact between the positive and negative electrodes leading to thermal runaway. The nail penetration tests were used to simulate an internal short circuit within the battery, where a conductive nail was used to pierce the battery cell separator membrane which provided direct electrical contact between the positive and negative electrodes. The batteries tested during this work were common batteries used in existing automotive applications, and they included a nickel manganese cobalt (NMC) battery from a Chevrolet Bolt, a lithium manganese oxide (LMO) battery from a Chevrolet Volt, and a lithium iron phosphate (LFP) battery in a hybrid transit bus. The battery abuse and emissions tests were designed to intentionally drive the three different battery chemistries into thermal runaway while measuring battery temperatures, battery voltages and gaseous emissions.

Internal short-circuit in cells/batteries is a phenomenon where there is direct electrical contact between the positive and negative electrodes leading to thermal runaway. The nail penetration tests were used to simulate an internal short circuit within the battery, where a conductive nail was used to pierce the battery cell separator membrane which provided direct electrical contact between the positive and negative electrodes. The batteries tested during this work were common batteries used in existing automotive applications, and they included a nickel manganese cobalt (NMC) battery from a Chevrolet Bolt, a lithium manganese oxide (LMO) battery from a Chevrolet Volt, and a lithium iron phosphate (LFP) battery in a hybrid transit bus. The battery abuse and emissions tests were designed to intentionally drive the three different battery chemistries into thermal runaway while measuring battery temperatures, battery voltages and gaseous emissions.

As the efforts to push capabilities of current engine hardware to their durability limits increases, more accurate and reliable analysis is necessary to ensure that designs are robust. This paper evaluates a method of Conjugate Heat Transfer (CHT) analysis for a gasoline and a diesel engine that combines combustion Computational Fluid Dynamics (CFD), engine Finite Element Analysis (FEA), and cooling jacket CFD with the goal of obtaining more accurate temperature distribution and heat loss predictions in an engine compared to standard de-coupled CFD and FEA analysis methods. This novel CHT technique was successfully applied to a 2.5 liter GM LHU gasoline engine at 3000 rpm and a 15.0 liter Cummins ISX heavy duty diesel engine operating at 1250 rpm. Combustion CFD simulations results for the gasoline and diesel engines are validated with the experimental data for cylinder pressure and heat release rate.

General agreement exists that the ultimate goals of traffic accident research are to reduce fatality, mitigate injury and decrease economic loss to society. Although massive quantities of data have been collected in local, national and international programs, attempts by analysts to use these data to explore ideas or support hypotheses have been met by a variety of problems. Specifically, the coded variables in the different files are not consistent and little information on accident etiology is collected. Examples of the inadequacies of present data in terms of the collected and coded variables are shown. The vehicular, environmental and human (consisting of human factors and injury factors) variables are disproportionately represented in most existing data files in terms of recognized statistical evidence of accident causation. A systems approach is needed to identify critical, currently neglected variables and develop units of measurement and data collection procedures.

Since the early 1990’s, commercial vehicles have suffered from repeated vulnerability exploitations that resulted in a need for improved automotive cybersecurity. This paper outlines the strategies and challenges of implementing an automotive Zero Trust Architecture (ZTA) to secure intra-vehicle networks. Zero Trust (ZT) originated as an Information Technology (IT) principle of “never trust, always verify”; it is the concept that a network must never assume assets can be trusted regardless of their ownership or network location. This research focused on drastically improving security of the cyber-physical vehicle network, with minimal performance impact measured as timing, bandwidth, and processing power. The automotive ZTA was tested using a software-in-the-loop vehicle simulation paired with resource constrained hardware that closely emulated a production vehicle network.

As the design of engines advances and continues to push the capabilities of current hardware closer to their durability limits, more accurate and reliable analysis is necessary to ensure that designs are robust. This research evaluates a method of conjugate heat transfer analysis for a diesel engine that combines the combustion CFD, Engine FEA, and cooling jacket CFD with the aim of getting more accurate heat loss predictions and a more accurate temperature distribution in the engine than with current analysis methods. A 15.0 L Cummins ISX heavy duty engine operating at 1250 RPM and 15 bar BMEP load is selected for this work. Spray combustion computational fluid dynamics (CFD) simulations are performed for the diesel engine and the results are validated with experimental data. Finite Element Analysis (FEA) simulations were performed in a separate software platform.

The U.S. Army has long identified the need for rapid, reliable methods for analysis of fuels and lubricants on or near the battlefield. The analysis of fuels and lubricants under battlefield or near-battlefield conditions requires that the equipment be small, portable, rugged, quick, and easy to use. Over the past 15 to 20 years, several test kits and portable laboratories have been developed in response to this need. One instrumental technique that has been identified as a likely candidate to meet this need is near-infrared spectroscopy (NIR). To evaluate NIR as a candidate, a set of 280 fuel samples was used. This sample set contained samples of diesel fuel grades 1 and 2, Jet A-l, JP-5, and JP-8. Inspection data were collected on all the fuels as sample size permitted. Each sample was then scanned using a near-infrared spectrometer. Data analysis, model building, and calibration were conducted using a software package supplied with the instrument.

Many studies on low speed pre-ignition have been published to investigate the impact of fuel properties and of lubricant properties. Fuels with high aromatic content or higher distillation temperatures have been shown to increase LSPI activity. The results have also shown that oil additives such as calcium sulfonate tend to increase the occurrence of LSPI while others such as magnesium sulfonate tend to decrease the occurrence. Very few studies have varied the fuel and oil properties at the same time. This approach is useful in isolating only the impact of the oil or the fuel, but both fluids impact the LSPI behavior of the engine simultaneously. To understand how the lubricant and fuel impacts on LSPI interact, a series of LSPI tests were performed with a matrix which combined fuels and lubricants with a range of LSPI activity. This study was intended to determine if a low activity lubricant could suppress the increased LSPI from a high activity fuel, and vice versa.

The primary objective of this study was to compare the performance of “new” plastic fuel tanks vs. “aged” plastic fuel tanks when subjected to the standard fire exposure test described in ECE R34.01, Annex 5 Section 5.0 “Resistance to Fire.” The program also included a comparison of failure modes of plastic vs. metal fuel tanks when subjected to a simulated post-crash pool fire. The “new” tanks were purchased from the OEM suppliers (not weathered or pre-conditioned with fuel). The “aged” tanks were obtained from vehicles that were operated in a warm climate and considered to be weathered and fully conditioned with fuel. Three vehicle types, representing three fuel tank shapes and installations, were evaluated: 1.) “thin profile” tank, typical of front wheel drive cars with the tank mounted on the underbody near the rear seat area and in front of the rear axle; 2.) “square profile” tank, typical of SUV's with the tank mounted behind the rear axle; and 3.)

Exhaust emission data from several fuel effects studies were normalized and subjected to statistical analyses. The goal of this work was to determine whether emission effects of property variation in alternate-source fuels were similar, less pronounced, or more pronounced than the effects of property variation in petroleum fuels. A literature search was conducted, reviewing hundreds of studies and finally selecting nine which dealt with fuel property effects on emissions. From these studies, 15 test cases were reported. Due to the wide variety of vehicles, fuels, test cycles, and measurement techniques used in the studies, a method to relate them all in terms of general trends was developed. Statistics and methods used included bivariate correlation coefficients, regression analysis, scattergrams and goodness-of-fit determinations.

Overcharging lithium-ion batteries is a failure mode that is observed if the battery management system (BMS) or battery charger fails to stop the charging process as intended. Overcharging can easily lead to thermal runaway in a battery. In this paper, nickel manganese cobalt (NMC) battery modules from the Chevrolet Bolt, lithium manganese oxide (LMO) battery modules from the Chevrolet Volt, and lithium iron phosphate (LFP) battery modules from a hybrid transit bus were overcharged. The battery abuse and emissions tests were designed to intentionally drive the three different battery chemistries into thermal runaway while measuring battery temperatures, battery voltages, gaseous emissions, and feedback from volatile organic compound (VOC) sensors. Overcharging a battery can cause lithium plating and other exothermic reactions that will lead to thermal runaway.

Alternative fuels are being evaluated in automotive applications in both commercial and government fleets in an effort to reduce emissions and United States dependence on diesel fuel. Vehicles and equipment have been operated using 100 percent biodiesel and various blends of biodiesel and diesel fuel in a variety of applications, including farming equipment and transit buses. This government study investigates the compatibility of four base fuels and six blends with elastomer and metallic components commonly found in fuel systems. The physical properties of the elastomers were measured according to American Society of Testing and Materials (ASTM) D 471, “Standard Test Method for Rubber Property-Effect of Liquids,” and ASTM D 412, “Standard Test Methods for Rubber Properties in Tension.” These evaluations were performed at 51.7°C for 0, 22, 70, and 694 hours. Tensile strength, hardness, swell, and elongation were determined for all specimens.

A comprehensive 3D Computational Fluid Dynamics (CFD) with conjugate heat transfer (CHT) tool was developed in-house for a Tesla Model 3 electric motor. To accurately predict the power loss (heat generation) inside the electric motor, the electromagnetic process was solved to obtain the spatial-dependent power loss in the rotor, stator, and windings. CFD was utilized for simulating the coolant oil flow using the multiphase Volume of Fluid (VOF) approach and Finite Element Analysis (FEA) was used for simulating the thermal process within the solid domains. These three separate analysis modules (electromagnetic, fluid flow and thermal solid) were coupled strongly to enable two-way interactions. Thermal results obtained from the final converged simulations were compared to the test data obtained from the thermocouple measurements for the two most representative operating points of this e-motor and showed reasonable predictions with similar trend as observed in the test.

A typical automotive catalytic converter is constructed with a ceramic substrate and a steel shell. Due to a mismatch in coefficients of thermal expansion, the steel shell will expand away from the ceramic substrate at high temperatures. The gap between the substrate and shell is usually filled with a fiber composite material referred to as “mat.” Mat materials are compressed during assembly and must maintain an adequate pressure around the substrate under extreme temperature conditions. The container deformation measurement procedure is used to determine catalytic converter shell expansion during and after a period of hot catalytic converter operation. This procedure is useful in determining the potential physical durability of a catalytic converter system, and involves measuring converter shell expansion as a function of inlet temperature. A post-test dimensional measurement is used to determine permanent container deformation.

This paper describes a new method for measuring oil consumption using laser induced breakdown spectroscopy (LIBS). LIBS focuses a high energy laser pulse on a sample to form a transient plasma. As the plasma cools, each element produces atomic emission lines which can be used to identify and quantify the elements present in the original sample. In this work, a LIBS system was used on simulated engine exhaust with a focus on quantifying the inorganic components (termed ash) of the particulate emissions. Because some of the metallic elements in the ash almost exclusively result from lube oil consumption, their concentrations can also be correlated to an oil consumption rate. Initial testing was performed using SwRI’s Exhaust Composition Transient Operation Laboratory®(ECTO-Lab®) burner system so that oil consumption and ash mass could be precisely controlled.

The State of Florida initiated the SunGuide® Advanced Traffic Management System (ATMS) software development program in October 2003; that software is deployed in over 15 Traffic Management Centers (TMCs) throughout the major cities in Florida. One of SunGuide's biggest strengths is a software architecture that allows for short development times for new functionality. This paper describes the system design, implementation, and lessons learned from the development of the SunGuide Connected Vehicle Subsystem (CVS). The SunGuide CVS receives real-time speed, location, and heading data from instrumented vehicles and uses that data in a manner similar to its use of traffic detector data to provide information to the TMC. In addition to the vehicle providing data to the TMC, the TMC may create and publish Traveler Advisory Messages to the vehicle as part of the SunGuide Event Management response plans.

An appropriate test procedure, based on a duty cycle representative of real in-use operation, is an essential tool for characterizing engine emissions. A study has been performed to develop and validate a snowmobile engine test procedure for measurement of exhaust emissions. Real-time operating data collected from four instrumented snowmobiles were combined into a composite database for analysis and formulation of a snowmobile engine duty cycle. One snowmobile from each of four manufacturers (Arctic Cat, Polaris, Ski-Doo, and Yamaha) was included in the data collection process. Snowmobiles were driven over various on- and off-trail segments representing five driving styles: aggressive (trail), moderate (trail), double (trail with operator and one passenger), freestyle (off trail), and lake driving. Statistical analysis of this database was performed, and a five-mode steady-state snowmobile engine duty cycle was developed.

Trained human raters have been used by organizations such as the Coordinating Research Council (CRC) to assess the vehicle driveability performance effect of fuel volatility. CRC conducts workshops to test fuel effects and their impact on vehicle driveability. CRC commissioned Southwest Research Institute (SwRI) to develop a “Trick Car” vehicle that could trigger malfunctions on-demand that mimic driveability events. This vehicle has been used to train novice personnel on the CRC Driveability Procedure E-28-94. While largely effective, even well-trained human raters can be inconsistent with other raters. Further, CRC rater workshop programs used to train and calibrate raters are infrequent, and there are a limited number of available trained raters. The goal of this program was to augment or substitute human raters with an electronic driveability sensing system.

This paper describes the development and evaluation of an operative catalyst for the reduction of NOx in lean exhaust. A catalyst that incorporates iron (II)-complex impregnated modified mesoporous molecular sieves (MCM-41) has been synthesized and further treated with [pd(NH3)4]Cl2 [1]. Experimental results suggest a hydrocarbon-independent reduction of NOx takes place on the iron center, and oxidation of CO is assisted by the palladium ion. The catalytic activity toward HC CO, and NOx removal was studied with simulated and real engine exhaust in the laboratory and on an engine, respectively. Engine test results demonstrate a reduction of NOx of up to 10 percent at catalyst inlet temperatures in the range of 260°C to 280°C. In this paper, possible NOx reduction pathways are also discussed.

Lithium plating refers to the phenomenon where lithium metal is deposited onto the surface of the anode instead of being intercalated into the carbon sites of the graphite. The lithium metal will cover a portion of the surface area of the anode, which blocks intercalation sites and increases charge gradients. Lithium plating most often occurs when charging the battery at low ambient temperatures or at a high current rate, but lithium plating formation has also been linked to solid electrolyte interface (SEI) growth towards the later stages of life. Lithium plating may significantly reduce a battery cell’s performance in terms of charge capacity, and if severe enough, the lithium metal may form a bridge across the separator of the cell, leading to short circuits and potential safety concerns. The internal research performed by Southwest Research Institute explored how to create a battery model to detect the formation of lithium plating in real time.