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Abstract The ASTM D130 was first issued in 1922 as a tentative standard for the detection of corrosive sulfur in gasoline. A clean copper strip was immersed in a sample of gasoline for three hours at 50°C with any corrosion or discoloration taken to indicate the presence of corrosive sulfur. Since that time, the method has undergone many revisions and has been applied to many petroleum products. Today, the ASTM D130 standard is the leading method used to determine the corrosiveness of various fuels, lubricants, and other hydrocarbon-based solutions to copper. The end-of-test strips are ranked using the ASTM Copper Strip Corrosion Standard Adjunct, a colored reproduction of copper strips characteristic of various degrees of sulfur-induced tarnish and corrosion, first introduced in 1954. This pragmatic approach to assessing potential corrosion concerns with copper hardware has served various industries well for a century.

Abstract Emissions development work for gasoline aftertreatment systems is often conducted in a laboratory on a chassis dynamometer. In this situation, extractive sample lines are frequently connected to the aftertreatment system before and after various components, such as a three-way catalyst, selective catalytic reduction substrate, and the like. This is done to measure the conversion efficiency of the aftertreatment system components as a function of time. The time series exhaust component concentration data, also referred to as continuous data, are combined with a measure of exhaust volumetric flowrate and used to calculate mass-based emissions. As gasoline powertrains become cleaner and produce lower levels of criteria emissions, the proximity (i.e., colocated or not colocated) of the volumetric flowrate and concentration measurements may affect the accuracy of the overall mass emission calculation.

Abstract An integrated electrically heated catalyst (EHC) in the three-way catalyst (TWC) of a gasoline internal combustion engine (ICE) is a promising technology to reduce engine cold-start pollutant emissions. Pre-heating the TWC ensures earlier catalyst light-off of a significant portion of the TWC. In such a case, the engine could readily be operated in a fuel-optimal manner since the engine cold-start emission is efficiently treated by the warmed-up EHC-equipped TWC. Pre-heating the EHC is an effective way to reduce cold-start emissions, among other possible EHC strategies. However, it might not always be possible to use pre-heating if the engine-start time is uncertain. In such a case, pre-heating can be started when the engine start is known with greater confidence and post-heating the catalyst could be followed. It would then be natural to turn off the EHC when the payoff for the electrical energy spent is no longer effective in engine cold-start emission reduction.

Abstract Catalytic converters have been effectively controlling the harmful exhaust gases to meet stringent emission norms. This article presents a new three-way catalyst developed using natural zeolite for effective emission reduction. The step-by-step preparation of the material for the developed catalyst is followed by its characterization using an energy dispersive X-ray (EDX), X-ray diffraction (XRD), and scanning electron microscope (SEM). The testing performed on a synthetic gas test bench (SGTB) shows substantial carbon monoxide (CO), hydrocarbon (HC), and nitric oxide (NO) reduction. Results show a 100% conversion for NO above 280°C, 54.8% for CO at 315°C, and 52% for HC at 500°C. The developed natural zeolite-based catalyst stands out from among current catalysts and can be endorsed for three-way conversions than the synthetic zeolite catalyst.

Abstract The urea-selective catalyst reduction system implemented in commercial vehicles facilitates ensuring compliance with the NOx regulation limit. A significant challenge in urea injection is to comprehend its decomposition chemistry that often leads to the formation of unfavorable deposits in the exhaust system unit. Due to the complex interaction of the multiphase fluid flow and transport processes, a significant degree of uncertainty is associated with the identification of the interacting factors that control the deposit initiation and its growth. A systematic investigation was conducted through numerous experiments to study the factors controlling the urea deposit that guides innovation for new product development. For the first time, the effect of pressure on urea deposits is investigated by heating an aqueous urea solution in a closed system maintained between 30 and 200 psi.

Abstract An investigation into the pre-ashing of new gasoline particulate filters (GPFs) has demonstrated that the filtration efficiency of such filters can be improved by up to 30% (absolute efficiency improvement) when preconditioned using ash derived from a fuel-borne catalyst (FBC) additive. The additive is typically used in diesel applications to enable diesel particulate filter (DPF) regeneration and can be added directly into the fuel tank of the vehicle. This novel result was compared with ash derived from lube oil componentry, which has previously been shown to improve filtration efficiency in GPFs. The lube oil-derived ash utilized in this work improved the filtration efficiency of the GPF by −30%, comparable to the ash derived from the FBC additive.

Abstract Biodiesel was found to be the best candidate to replace diesel fuel mainly due to being renewable, biodegradable, and non-toxic and reduce greenhouse gases, which cause global warming. Nowadays, biodiesel is blended with diesel fuel in different concentrations depending on the country of usage and is used in diesel engines. Concerns about biodiesel were raised after premature fouling of fuel filters were reported before meeting their mileage requirement. Three filters from Brazil were analyzed using different techniques (Energy Dispersive X-Ray [EDX], Fourier Transform Infrared Spectroscopy [FTIR], Thermogravimetric Analysis [TGA], Time of Flight-Secondary Ion Mass Spectrometry [ToF-SIMS], and Gas Chromatography/Mass Spectrometry [GC/MS]) to understand the chemical composition of the filter deposits and highlight the main compounds responsible for the blockage.

Abstract Oxides of nitrogen (NOx) represent unwanted by-products from combustion of fossil fuels. NOx can cause significant harm to living beings through decreased air quality. This review summarizes the sources of NOx emissions, regulations established to limit these emissions from on-road transportation, and the technologies developed by the automotive industry to meet these requirements. As regulations continue to establish lower limits for NOx emissions, engine and power technologies are evolving to meet these requirements. Exhaust aftertreatment systems have enabled near-zero tailpipe NOx emissions using NOx reduction catalysts. These catalysts are being further developed for improved low-temperature performance and higher durability. Such improvements are enabled through fundamental understanding of the underlying chemistry governing these catalytic processes.

Abstract An ongoing challenge with Gasoline engines is achieving rapid activation of the three-way catalyst during cold starts in order to minimize pollutant emissions. Retarded combustion is an effective way in achieving rapid light-up of the three-way catalyst and can be facilitated by stratified charge using late fuel injection. This, however, provides insufficient time for fuel entrainment with air, resulting in locally fuel-rich diffusion combustion. Employing a split injection strategy can help tackle these issues. The effects of a split injection strategy, using a high-pressure Solenoid injector, on the in-cylinder charge formation are investigated in the current study. The studies are performed inside an optical Gasoline engine using high-speed particle image velocimetry (PIV) in the central tumble and Omega tumble planes, by means of a high-speed laser and camera operating at a repetition rate of 10 kHz.

Abstract Sustainable practices are taking precedence across many industries, as evident from their shift towards the use of environmentally responsible materials, such as natural fiber-reinforced acrylated epoxidized soybean oil (NF-AESO). However, due to the lower reactivity of AESO, the curing reaction usually requires higher temperatures and longer curing time (e.g., 150°C for 6-12 h), thus making the entire process unsustainable. In this study, we demonstrate the potential power of photons towards manufacturing NF-AESO composites in a sustainable manner at room temperature (RT) within 10 min. Two photoinitiators, i.e., the 2,2-dimethoxy phenylacetophenone (DMPA) and 1-hydroxycyclohexyl phenyl ketone (HCPK), were evaluated and compared with the thermal initiator, i.e., tert-butyl perbenzoate (TBPB). Based on the mechanical performance of the AESOs, the photoinitiation system for NF-AESO was optimized.

Abstract Uncertainty of fuel reserves, environmental crisis, and health concerns arise from transport demands and reliance on fossil fuels. Downsized gasoline turbocharged direct injection (GTDI) engines have been developed and applied to most modern gasoline vehicles, delivering superior efficiency in high-load operation, reduced friction, and weight. But fuel enrichment and late combustion phasing to mitigate knocking combustion have hindered the efficiency benefits at higher loads with high boost. Furthermore, the wide valve-overlap with a three-cylinder setup for the maximum scavenging efficiency produces bursts of short-circuit (SC) air to cause underestimation of the equivalence ratio by the oxygen sensor, resulting in higher tailpipe nitrogen oxides (NOx) emissions with three-way catalyst (TWC) exhaust aftertreatment. Reducing the valve overlap to limit short-circuiting and enrichment will recover the combustion efficiency and the engine ER, but at the cost of high knock onset.

Abstract The energy management of hybrid electric vehicles (HEVs) is a complex subject that can be addressed with the tools provided by optimal control theory. Optimization algorithms explored so far in the literature, like dynamic programming (DP) or equivalent consumption minimization strategy (ECMS), have systematically analyzed the potential CO2 reduction for different topologies and degree of hybridization. However, the management of engine and electric machine (EM) neglects that the catalyst material in the aftertreatment system needs to reach a certain temperature to properly convert pollutant emissions. In this study, the thermal management of the catalyst in a gasoline HEV has been investigated, and two algorithms have been proposed. Two strategies based on the ECMS are presented: the first one explicitly considers the catalyst temperature; the second one keeps the underlying structure of ECMS, but it adds a high-level rule to indirectly encompass catalyst management.

Abstract Engine oils have complex packages of additives aimed at improving their tribological properties. However, interactions between elements of these additives may hinder the cooling ability of these oils. The current article addresses the influence of the interaction between chemical elements of oil additives on the cooling capacity of oils for different wall superheats (0°C-150°C) and oil bulk temperatures (60°C, 100°C, and 150°C). A back-propagation neural network (BPNN) is used to conduct the present work. The NN is trained on experimental heat transfer data of five commercial engine oils. Enhancement intensity, interaction sensitivity, and interaction stability of additive elements are investigated for the range of element concentrations of the experimental dataset.

Abstract Epoxies, synthesized from bisphenol-A (BPA) and epichlorohydrin (ECH), are predominantly used as coatings, adhesives, and matrix material in fiber-reinforced composites for body-in-white (BiW) applications in the automotive sector. However, given the production of conventional epoxies from nonrenewable petroleum resource and toxicity of BPA, several initiatives have been undertaken by researchers to synthesize alternative epoxies from various bio-sources that are free of BPA and exhibit similar mechanical performance. As a result, such bio-sourced epoxies are almost immediately termed as “ecofriendly,” despite the lack of comprehensive evaluation of their ecological performance that takes into account enhanced natural resource usage and associated impacts accompanying such epoxies.

Abstract Nitrous oxide (N2O) is both an ozone depleting gas and a potent greenhouse gas (GHG), having a global warming potential (GWP) value nearly 300 times that of carbon dioxide (CO2). While long known to be a trace by-product of combustion, N2O was not considered a pollutant of concern until the introduction of the three-way catalyst (TWC) on light-duty gasoline vehicles in the 1980s. These precious metal-containing catalysts were found to increase N2O emissions substantially. Through extensive research efforts, the effects of catalyst type, temperature, air/fuel ratio, space velocity, and other factors upon N2O emissions became better understood. Although not well documented, N2O emissions from non-catalyst vehicles probably averaged 5-10 mg/mi (on the standard FTP test), while early generation TWC-equipped vehicles exceeded 100 mg/mi. As emissions control systems evolved to meet increasingly stringent criteria pollutant standards, N2O emissions also decreased.

Abstract The purpose of this article is to study the antifriction and anti-wear effect of GCr15 bearing steel under paraffin base oil and the base oil with two additives of T405 sulfurized olefin and nano-MoS2 and compare the synergistic lubrication effect of two different additives (MoS2 and T405) in paraffin base oil. The tribological properties of GCr15 bearing steel under different lubrication conditions were tested on a ball-on-disk tribometer. The three-dimensional profile of disk’s worn surfaces and the scanning electron microscope (SEM) micrographs of corresponding steel balls were analyzed at the same time. The wettability of lubricating oils on the surface of friction pairs and the dispersibility of MoS2 in base oil were characterized.

Abstract Metal Pick-Up (MPU) is a problematic phenomenon in automotive disc brakes. MPU generally forms as some metal lumps on the surface of the brake pad. If brake pads have MPU, during braking they would cause grooving of the disc rotor, generating brake noise and deteriorating the performance of the brake. The previous literature has so far reported that the source of the MPU is an Fe component from a disc rotor or brake pads. However, only a few of the generation mechanisms of MPU have been proven. We investigate MPU to completely elucidate the mechanism of MPU generation by using different analyses than the previous literature. First, to find out the source of MPU generation, we focus on the chemical reaction of a certain component with wear debris during braking, and some of the verification experiments are conducted under the conditions of simulated friction interface.

Abstract Continuously tightening Particulate Matter (PM) and Particulate Number (PN) regulations make Gasoline Particulate Filters (GPFs) with high filtration efficiency and low pressure drop highly desirable as Gasoline Direct Injection (GDI) engines increase in market share. Due to packaging constraints, GPFs are often coated with three-way catalyst (TWC) materials to achieve four-way functionality. Therefore, it is critical to investigate the effects of various washcoating strategies on GPF performance. A three-dimensional (3D) Computational Fluid Dynamics (CFD) model, along with an analytical filtration model was created. A User Defined Function (UDF) was implemented to define the heterogeneous properties of the GPF wall due to washcoating or ash membrane application. The model demonstrated the ability to predict transient filtration efficiency and pressure drop of uncoated and washcoated GPFs.

Abstract Different aftertreatment systems consisting of a combination of selective catalytic reduction (SCR) and SCR catalyst on a diesel particulate filter (DPF) (SCR-F) are being developed to meet future oxides of nitrogen (NOx) emissions standards being set by the Environmental Protection Agency (EPA) and the California Air Resources Board (CARB). One such system consisting of a SCRF® with a downstream SCR was used in this research to determine the system NOx reduction performance using experimental data from a 2013 Cummins 6.7L ISB diesel engine and model data. The contribution of the three SCR reactions on NOx reduction performance in the SCR-F and the SCR was determined based on the modeling work. The performance of a SCR was simulated with a one-dimensional (1D) SCR model. A NO2/NOx ratio of 0.5 was found to be optimum for maximizing the NOx reduction and minimizing NH3 slip for the SCR for a given value of ammonia-to-NOx ratio (ANR).

Engineering plastics are widely used in many tribological applications due to their inherent advantages such as reduced weight, ease of manufacturing, improved chemical compatibility, and damping characteristics. However, the process of selecting an appropriate polymeric material system for a specific application involves significant experimentation.