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RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.

EcoCAR 3 is a university based competition with the goal of hybridizing a 2016 Chevrolet Camaro to increase fuel economy, decrease environmental impact, and maintain user acceptability. To achieve this goal, university teams across North America must design, test, and implement automotive systems. The Colorado State University (CSU) team has designed a parallel pretransmission plug in hybrid electric design. This design will add torque from the engine and motor onto a single shaft to drive the vehicle. Since both the torque generating devices are pre-transmission the torque will be multiplied by both the transmission and final drive. To handle the large amount of torque generated by the entire powertrain system the vehicle's rear half-shafts require a more robust design. Taking advantage of this, the CSU team has decided to pursue the use of composites to increase the shaft's robustness while decreasing component weight.

Dedicated Exhaust Gas Recirculation (D-EGR®) technology provides a novel means for fuel efficiency improvement through efficient, on-board generation of H2 and CO reformate [1, 2]. In the simplest form of the D-EGR configuration, reformate is produced in-cylinder through rich combustion of the gasoline-air charge mixture. It is also possible to produce more H2 by means of a Water Gas Shift (WGS) catalyst, thereby resulting in further combustion improvements and overall fuel consumption reduction. In industrial applications, the WGS reaction has been used successfully for many years. Previous engine applications of this technology, however, have only proven successful to a limited degree. The motivation for this work was to develop and optimize a WGS catalyst which can be employed to a D-EGR configuration of an internal combustion engine. This study consists of two parts.

Water injection (WI) can improve gasoline engine performance and efficiency, and on-board water recovery technology could eliminate the need for customers to refill an on-board water reservoir. In this regard, the technical feasibility of exhaust water recovery (EWR) is described in this paper. Water injection testing was conducted at a full load condition (5000 rpm/18.1 bar BMEP) and a high load condition (3000 rpm/14.0 bar BMEP) on a turbocharged gasoline direction injection (GTDI) engine. Water recovery testing was conducted both after the exhaust gas recirculation (EGR) cooler and after the charge air cooler (CAC) at a high load (3000 rpm/14.0 bar BMEP), as well as a part load (2080 rpm/6.8 bar BMEP) condition, at temperatures ca. 10-15 °C below the dew point of the flow stream. Three types of water separation designs were tested: a passive cyclone separator (CS), a passive membrane separator (MEM), and an active separator (AS).

The objectives of this project were to investigate the corrosivity of condensate in a stoichiometric spark-ignited (SI) engine when running exhaust gas recirculation (EGR) and to determine the effects of sulfur-in-fuel on corrosion. A 2.0 L turbocharged direct-injected SI engine was operated with low-pressure EGR for this study. The engine was instrumented for visual, thermodynamic, and electrochemical analyses to determine the potential for corrosion at locations where condensation was deemed likely in a low-pressure loop EGR (LPL-EGR) engine. The electrochemical analysis was performed using multi-electrode array (MEA) corrosion probes. Condensate was also collected and analyzed. These analyses were performed downstream of both the charge air cooler (CAC) and the EGR cooler. It was found that while conditions existed for sulfuric acid to form with high-sulfur fuel, no sulfuric acid was detected by any of the measurement methods.

A 28-vehicle fleet test was executed to verify and quantify the NOX emissions reductions achieved through the use of Infineum's Vektron 6913 gasoline additive. The fleet composition and experimental design were finalized in collaborative discussions with US Environmental Protection Agency (EPA) Office of Transportation & Air Quality (OTAQ) and consultation / advice from several major US automotive manufacturers. The test was conducted over a period of five months at Southwest Research Institute. Statistical analysis of the emissions data indicated a 10% average fleet reduction in NOX emissions without any negative impact on other criteria pollutants (CO, HC) or fuel economy.

Prediction of vehicle velocity is important since it can realize improvements in the fuel economy/energy efficiency, drivability, and safety. Velocity prediction has been addressed in many publications. Several references considered deterministic and stochastic approaches such as Markov chain, autoregressive models, and artificial neural networks. There are numerous new sensor and signal technologies like vehicle-to-vehicle and vehicle-to-infrastructure communication that can be used to obtain inclusive datasets. Using these inclusive datasets of sensors in deep neural networks, high accuracy velocity predictions can be achieved. This research builds upon previous findings that Long Short-Term Memory (LSTM) deep neural networks provide low error velocity prediction. We developed an LSTM deep neural network that uses different groups of datasets collected in Fort Collins, Colorado.

A survey of vehicle refueling practices in California during the gasoline shortage of 1979 indicates that the use of leaded gasoline in catalyst equipped vehicles was occurring at a rate of about 1.6%. This 1.6% “misfueling” rate is lower than has been predicted by the U.S. Environmental Protection Agency and is almost exclusively the result of the refueling that occurs at self-service gasoline pumps. About three-quarters of the misfueled vehicles were apparently operated on leaded gasoline routinely. Based on the effect that leaded fuel has on the exhaust emission characteristics of catalyst equipped vehicles it is estimated that misfueling in California is increasing hydrocarbon and carbon monoxide emissions by about 4% and 1.6%, respectively from late model passenger cars.

There have been a half dozen surveys performed by the California Air Resources Board in California from December, 1977 to July, 1982 to determine the rate of vehicle misfueling in California. There has been great concern raised over misfueling which leads to the poisoning of catalysts and the subsequent increases in emissions of hydrocarbons, carbon monoxide and oxides of nitrogen. The results of observing refueling at service stations indicate a misfueling rate of about 2% which is much lower than what the U. S. Environmental Protection Agency figures indicate. Misfueling at self-serve stations is more than twice that noted at full-serve stations. The primary reasons given by motorists for misfueling are cheaper price of unleaded gasoline, performance (including pinging) and unavailability of unleaded fuel. Misfueling was accomplished primarily as a result of a modified restrictor or filler neck.

Current California law requires the implementation of a mandatory annual vehicle emissions inspection and maintenance program in the South Coast Air Basin by 1978. The pilot phase of this inspection program is now in operation in the City of Riverside. This paper evaluates the Riverside program and an alternate program for their abilities to detect gross emitters and provide cost/effective emissions reductions. A surveillance program was conducted to evaluate the Riverside loaded-mode inspection regime and an alternate idle inspection regime. Emissions and fuel economy tests indicated that there was no significant difference between the two regimes. Each regime resulted in immediate reductions on repaired vehicles of 35-40% in hydrocarbon emissions and 30-35% in carbon monoxide emissions, with no significant change in oxides of nitrogen emissions. There was a small (1-4%) improvement in fuel economy, and the average repair cost was $20-25.

Vehicle exhaust emissions measurements are reported for full-size panel vans operating on four alternative motor fuels and control gasoline. The emissions tests produced data on in-use vans. The vans were taken directly from commercial delivery service for testing as they accumulated mileage over a 24-month period. The alternative fuels tested were compressed natural gas, propane gas, California Phase 2 reformulated gasoline (RFG), and methanol (M-85 with 15 percent RFG). The control gasoline for the emissions tests was an industry average unleaded blend (RF-A). The vehicle technologies tested represent those options available in 1992 that were commercially available from Ford, Chrysler, and Chevrolet or which these manufacturers agreed to provide as test vans for daily use in commercial service by FedEx.

The environmental implications of converting vehicles powered by Internal Combustion Engines (ICE) to battery powered and hybrid battery/ICE powered are evaluated for the case of Chile, one of the worldwide leaders in the production of lithium (Li) required for manufacturing of Li-ion batteries. The economic and environmental metrics were evaluated by techno-economic analysis (TEA) and Life Cycle Assessment (LCA) tools - SuperPro Designer and Gabi®/GREET® models. The system boundary includes both the renewable and nonrenewable energy sources available in Chile and well-to-pump energy consumptions and GHG emissions due to Li mining and Li-ion battery manufacturing. All the major input data required for TEA and LCA were generated using Autonomie vehicle modeling software. This study compares economic and environmental indicators of three vehicle models for the case of Chile including compact, mid-size, and a light duty truck.

A special vehicle dynamometer has been developed that allows engineers to evaluate driveline components and control algorithms for advanced, electrically-assisted drive systems on commercial vehicles. This dynamometer allows objective measurements of performance, fuel economy, and exhaust emissions, while the full vehicle is operated over a specified driving cycle. This system can be used to exercise the electric motor, engine, transmission and battery systems on Medium Duty Hybrid Trucks - in regeneration as well as power mode - all indoors and in a controlled, repeatable environment. This paper will provide descriptions of the operating goals, control features, and results of testing with this dynamometer. Once the various parameters have been optimized for fuel and emissions performance in this facility, the vehicle can be evaluated where it counts - on the road.

The confluence of fuel economy improvement requirements and increased use of ethanol as a gasoline blend component has led to various studies into the efficiency and performance benefits to be had when using high octane number, high ethanol content fuels in modern engines. As part of a comprehensive study of the autoignition of fuels in both the CFR octane rating engine and a modern, direct injection, turbocharged spark ignited engine, a series of fuel blends were prepared with market relevant ranges of octane numbers and ethanol blends levels. The paper reports on the first part of this study where fuel flow measurements were done on a single cylinder research engine, utilizing a GM LHU combustion system, and then used to predict drive cycle fuel economy. For a range of engine speeds and manifold air pressures, spark timing was adjusted to achieve either the maximum brake torque (MBT) or a matched 50 % mass fraction burnt location.

Vegetable oils are candidates for alternative fuels in diesel engines. These oils, such as soybean, sunflower, rapeseed, cottonseed, and peanut, consist of various triglycerides. The chemistry of the degradation of vegetable oils when used as alternate diesel fuels thus corresponds to that of triglycerides. To study the chemistry occurring during the precombustion phase of a vegetable oil injected into a diesel engine, a reactor simulating a diesel engine was constructed. Pure triglycerides were injected into the reactor in order to determine differences in the precombustion behavior of the various triglycerides. The reactor allowed motion pictures to be prepared of the injection event as the important reaction parameters, such as pressure, temperature, and atmosphere were varied. Furthermore, samples of the degradation products of precombusted triglycerides were collected and analyzed (gas chromatography / mass spectrometry).

Sintered valve guides are increasingly used in various engine applications due to their superior durability and cost. Typical valve guide materials are low alloyed materials of the type Fe-Cu-C. More severe applications may require higher alloying content. One such application is EGR where the exhaust temperatures are much higher as compared to the conventional automotive valve guide. A new material was developed to work in this harsh environment. The object of this paper is to report development of this material including material properties and durability test results.

Studies have shown that obtaining and utilizing information about the future state of vehicles can improve vehicle fuel economy (FE). However, there has been a lack of research into whether near-term technologies can be utilized to improve FE and the impact of real-world prediction error on potential FE improvements. In this study, a speed prediction method utilizing simulated vehicle-to-vehicle (V2V) communication with real-world driving data and a drive cycle database was developed to understand if incorporating near-term technologies could be utilized in a predictive energy management strategy to improve vehicle FE. This speed prediction method informs a predictive powertrain controller to determine the optimal engine operation for various prediction durations. The optimal engine operation is input into a validated high-fidelity fuel economy model of a Toyota Prius.

Reactivity Controlled Compression Ignition (RCCI) natural gas/diesel dual-fuel combustion has been shown to achieve high thermal efficiency with low NOX and PM emissions, but has traditionally been limited to low to medium loads. High BMEP operation typically requires high substitution rates (i.e., >90% NG), which can lead to high cylinder pressure, pressure rise rates, knock, and combustion loss. In previous studies, compression ratio was decreased to achieve higher load operation, but thermal efficiency was sacrificed. For this study, a multi-cylinder heavy-duty engine that has been modified for dual-fuel operation (diesel direct-injection and natural gas (NG) fumigated into the intake stream) was used to explore RCCI and other dual-fuel combustion modes at high compression ratio, while maintaining stock lug curve capability (i.e., extending dual-fuel operation to high loads where conventional diesel combustion traditionally had to be used).

This paper describes experiments conducted to determine the regulated emissions, ozone-forming potentials, specific reactivities, and reactivity adjustment factors for eight butane and propane alternative fuel blends run on a light-duty vehicle, emission certified to be a California transitional low emission vehicle (TLEV) and converted to operate on liquefied petroleum gas (LPG). Duplicate EPA FTP emission tests were conducted with each fuel. Hydrocarbon speciation was utilized to determine reactivity-adjusted non-methane organic gases (NMOG) emissions for one test on each fuel. Results showed that all eight fuels could allow the converted vehicle to pass California ultra-low emission vehicle (ULEV) NMOG and oxides of nitrogen (NOx) standards. Six of the eight fuels could allow the vehicle to pass ULEV carbon monoxide (CO) standards. BUTANE has been an important gasoline blending component for many years.

The use of alcohol as a supplemental fuel for a medium-speed diesel engine was investigated using a two-cylinder, two-stroke test engine. Both stabilized and unstabilized emulsions of methanol-in-diesel fuel and ethanol-in-diesel fuel were tested. Also, anhydrous ethanol/diesel fuel solutions were evaluated. Maximum alcohol content of the emulsions and solutions was limited by engine knocking due to a reduction in fuel cetane number. Engine power and thermal efficiency were slightly below baseline diesel fuel levels in the high and mid-speed ranges, but were somewhat improved at low speeds during tests of the unstabilized emulsions and the ethanol solutions. However, thermal efficiency of the stabilized emulsions fell below baseline levels at virtually all conditions.