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Ethanol fuel has received renewed attention in recent years because of its oxygenate content and its potential to reduce greenhouse gas emissions from spark ignition engines. The economic impact on farm industry has been one of the drivers for its use in engines in the U.S. Although ethanol, in various blends, has been used in automotive engines for almost a decade the fuel has seldom been utilized in off-highway engines where the fuel systems are not well controlled. This investigation was conducted to evaluate exhaust emissions and combustion characteristics of E85 fuel in an off-highway engine used in farm equipment. A single-cylinder, four-stroke, spark ignition engine equipped with a carburetor was used to investigate combustion and exhaust emissions produced by gasoline and blends of gasoline and ethanol fuels. The engine fuel system was modified to handle flow rates required by the engine. A variable size-metering orifice was used to control air-to-fuel ratios.

Most of the present electric vehicle (EV) on-board chargers utilize a conventional design, i.e., a boost-type Power Factor Correction (PFC) controller followed by an isolated DC/DC converter. Such design usually yields a ~94% wall-to-battery efficiency and 2~3kW/L power density at most, which makes a high-power charger, e.g., 20kW module difficult to fit in the vehicle. As described in this paper, first, an E-mode GaN HEMT based 7.2kW single-phase charger was built. Connecting three such modules to the three-phase grid allows a three-phase >20kW charger to be built, which compared to the conventional three-phase charger, saves the bulky DC-bus capacitor by using the indirect matrix converter topology. To push the efficiency and power density to the limit, comprehensive optimization is processed to optimize the single-phase module through incorporating the GaN HEMT switching performance and securing its zero-voltage switching.

Controller Area Network (CAN), the de facto standard for in-vehicle networks, has insufficient security features and thus is inherently vulnerable to various attacks. To protect CAN bus from attacks, intrusion detection systems (IDSs) based on advanced deep learning methods, such as Convolutional Neural Network (CNN) and Recurrent Neural Network (RNN), have been proposed to detect intrusions. However, those models generally introduce high latency, require considerable memory space, and often result in high energy consumption. To accelerate intrusion detection and also reduce memory requests, we exploit the use of Binarized Neural Network (BNN) and hardware-based acceleration for intrusion detection in in-vehicle networks. As BNN uses binary values for activations and weights rather than full precision values, it usually results in faster computation, smaller memory cost, and lower energy consumption than full precision models.

A GT-suite commercial code was used to develop a fully integrated model of a light duty commercial vehicle with a V6 diesel engine, to study the use of a BorgWarner dual mode coolant pump (DMCP) in active thermal management of the vehicle. An Urban Dynamometer Driving Schedule (UDDS) was used to validate the simulation results with the experimental data. The conventional mechanical pump from the validated model was then replaced with the dual mode coolant pump. The control algorithm for the pump was based on controlling the coolant temperature with pump speed. Maximum electrical speed of the pump and the efficiency of the pump were used to determine whether the pump should run in mechanical or electrical mode. The model with the dual mode coolant pump was simulated for the UDDS cycle to demonstrate the effectiveness of control strategy.

The Honda Particulate Matter Index (PMI) is a very helpful tool which provides an indication of a fuel’s sooting tendency. Currently, the index is being used by various laboratories and vehicle OEMs as a metric to understand a fuels impact on automotive engine sooting, in preparation for new global emissions regulations. The calculation of the index involves generating detailed hydrocarbon analysis (hydrocarbon molecular speciation) using gas chromatography laboratory equipment and the PMI calculation requires the exact list of compounds and correct naming conventions to work properly. The analytical methodology can be cumbersome, when the gas chromatography methodology has to be adjusted for new compounds that are not in the method, or if the compounds are not matching the list for quantification. Also, the method itself is relatively expensive, and not easily transferrable between labs.

This paper presents a comparison of aqueous corrosion rates in 5% NaCl solution for eight experimental creep-resistant magnesium alloys considered for automotive powertrain applications, as well as three reference alloys (pure magnesium, AM50B and AZ91D). The corrosion rates were measured using the techniques of titration, weight loss, hydrogen evolution, and DC polarization. The corrosion rates measured by these techniques are compared with each other as well as with those obtained with salt-spray testing using ASTM B117. The advantages and disadvantages of the various corrosion measurement techniques are discussed.

Regulations on exhaust emissions from light- and heavy-duty diesel engines have generated interest in high-pressure fuel injection systems. It has been recognized that high-pressure injection systems produce fuel sprays that may be more conductive to reducing exhaust emissions in direct-injection diesel engines. However, for such a system to be effective it must be matched carefully with the engine design and its operating parameters. A common-rail type of fuel injection system was investigated in the present study. The injection system utilizes an intensifier to generate injection pressures as high as 160 MPa. The fuel spray characteristics were evaluated on a test bench in a chamber containing pressurized nitrogen gas. The injection system was then incorporated in a single-cylinder diesel engine. The injection system parameters were adjusted to match engine specifications and its operating parameters.

Gasoline-ethanol blends are being used or have been considered as a fuel for spark ignition engines. The motivation for using the blends varies in indifferent parts of the world and even in regions within a country. The increasing cost of gasoline, combined with regional tax incentives, is one of the reasons for increased interests in gasoline-ethanol blends in recent years in the U.S. Many vehicular engines are not designed to use a specific gasoline-ethanol blend. Rather, the engines have multi-blend capability, ranging from E0 to about E85. It is plausible that engine-out emissions will vary depending on the blend being used which may be further impacted by the level of EGR used with the blends. The present work was carried out to investigate engine out emissions when a vehicular spark-ignition engine was operated on E0 and E85 and different levels of EGR. A 4-cylinder, 2.5 liter, PFI engine was used in the experimental investigation.

A study was conducted to investigate combustion variability and exhaust emissions from high-speed, natural gas fueled engines. Two types of fuel systems were used in the investigation: a mixer and a port fuel injection. The overall engine performances were not much different at stoichiometric fuel-air ratio. But as the equivalence ratio was reduced the engine with the mixer produced higher levels of hydrocarbons and larger coefficient of variations in imep. The same engine exhibited longer flame development angle and rapid burn duration in comparison to the fuel injected engine. The differences in burn durations increased as the equivalence ratio decreased and the mixer system produced larger variations in their values at these operating points. The investigation showed the performance of the engine was better with natural gas injection system than with the mixer, particularly at lean equivalence ratios.

Semi-trucks, specifically class-8 trucks, have recently become a platform of interest for autonomy systems. Platooning involves multiple trucks following each other in close proximity, with only the lead truck being manually driven and the rest being controlled autonomously. This approach to semi-truck autonomy is easily integrated on existing platforms, reduces delivery times, and reduces greenhouse gas emissions via fuel economy benefits. Level 1 SAE fuel studies were performed on class-8 trucks operating with the Auburn Cooperative Adaptive Cruise Control (CACC) system, and fuel savings up to 10-12% were seen. Enabling platooning autonomy required the use of radar, global positioning systems (GPS), and wireless vehicle-to-vehicle (V2V) communication. Poor measurements and state estimates can lead to incorrect or missing positioning data, which can lead to unnecessary dynamics and finally wasted fuel.

A new 2.0 ℓ DOHC 4-valve direct injection (DI) gasoline engine has been developed which features new technologies such as swirl intake ports to produce an optimum swirl in the cylinder by variable controlled swirl control valve, pistons with a concave combustion chamber, and high pressure fuel injection system to provide a fine fuel-air mixture cloud in the combustion chamber. These all help to control fuel-air mixture preparation and flame propagation under ultra lean, stratified combustion at partial loads. NOx emission is reduced by using an electrically controlled EGR system and an NOx storage-reduction catalyst. At higher loads, a homogeneous mixture is obtained with direct injection during the intake stroke. A seamless output torque transition between stratified charge and homogeneous charge condition is achieved by an electronic throttle control system.

Toyota Motor Corporation has developed a dedicated compressed natural gas (CNG) powered vehicle “Camry” sedan to achieve near zero emissions and to meet rising demand for alternative fuel. A new engine that uses CNG as fuel has been developed by modifying the base 2.2 liter gasoline engine. In the unmodified base engine, torque and power for CNG decrease compared to gasoline. The new engine has adopted a high compression ratio, intake valves with early closed timing, intake and exhaust valves with increased lift and a low back pressure muffler, which thereby restored the loss of engine power. In order to greatly reduce exhaust emissions, a multi port injection system was chosen, and the injectors and pressure regulator have been newly developed. At the same time, precise A/F ratio control and special catalysts for CNG exhaust gas have been utilized.

Recent stringent government regulations on emission control and fuel economy drive the vehicles and their associated components and systems to the direction of lighter weight. However, the achieved lightweight must not be obtained by sacrificing other important performance requirements such as manufacturability, strength, durability, reliability, safety, noise, vibration and harshness (NVH). Additionally, cost is always a dominating factor in the lightweight design of automotive products. Therefore, a successful lightweight design can only be accomplished by better understanding the performance requirements, the potentials and limitations of the designed products, and by balancing many conflicting design parameters. The combined knowledge-based design optimization procedures and, inevitably, some trial-and-error design iterations are the practical approaches that should be adopted in the lightweight design for the automotive applications.

This paper presents results of a research project conducted to develop a methodology and to refine the specifications of a small, low mass, low cost vehicle being developed at the University of Michigan-Dearborn. The challenge was to assure that the design would meet the needs and expectations of customers in three different countries, namely, China, India and the United States. U.S, Chinese and Indian students studying on the university campus represented customers from their respective countries for our surveys and provided us with the necessary data on: 1) Importance of various vehicle level attributes to the entry level small car customer, 2) Preferences to various features, and 3) Direction magnitude estimation on parameters to size the vehicle for each of the three markets.

In Japan, Multipurpose vehicles (MPVs) are growing in popularity while sedan popularity is falling. Four wheel drive (4WD) systems on MPVs require wide range torque distribution because the vertical load distribution on the front and rear tires changes greatly. In order to satisfy this requirement for 4WD , Toyota Motor Corporation and Toyoda Machine Works LTD. have developed a new electronically controlled 4WD system named “Active Torque Control 4WD”. This system, by optimum driving force distribution, provides both good handling characteristics and low fuel consumption. And it enables compact drive-line size and light weight. This paper describes the development aims of the new system, its construction, its control and technological features.

With increasing use of biofuels in the automotive industry, it has become necessary to evaluate their effects on the properties of polymers used in the fuel delivery systems. In this study, we have considered the effect of biodiesel on the tensile properties of nylon-6, 30% E-glass fiber reinforced nylon-6 and impact-modified nylon-6. The tensile specimens were immersed in 100% biodiesel for up to 7 days before determining their tensile properties. Another set of specimens were immersed in 100% biodiesel under stressed condition and then their tensile properties were determined. The absorption of biodiesel and their effects on tensile modulus, tensile strength and failure strain are reported in this paper.

The effects of fuel properties and emission control systems on exhaust hydrocarbon emissions have been studied. Using fourteen fuels with different properties, exhaust hydrocarbon emissions were measured for the two vehicle types with different emission control systems, under body catalyst and closed coupled catalyst, under the Federal Test Procedure. The fuel properties included high and low concentrations of olefins and aromatics as well as high and low T90. In addition, two fuels contained MTBE. The hydrocarbon emissions were discussed from the view point of the ozone reactivity and ozone formation potential. The results show that the high ozone reactivity of exhaust emissions are mainly caused by the olefins and aromatics in fuels. And also, the effects of fuel property change on exhaust emissions for the vehicle with an under body catalyst are more sensitive than the case of the vehicle with a closed coupled catalyst.

An experimental study was undertaken to investigate emissions of hydrocarbons, oxides of nitrogen, carbon monoxide, and methane hydrocarbons emitted by natural gas fueled engines and the extent of their conversion in catalysts. Two engines were used in the study: a four cylinder, 1.6 liter, spark ignition engine and a modified version of the same engine with only one of the cylinders operating at 0.4 liter capacity. Two-way and three-way catalysts were used to treat exhaust gases leaving the engine. Natural gas was supplied through gas carburetors operated at regulated pressures and supplying air-fuel ratios in the desired range. The results of the investigation showed that oxides of nitrogen could not be reduced in a three-way catalyst to the levels found in gasoline fueled engines when the operating air-fuel ratio was stoichiometric.

The article solves the problem of increasing the energy efficiency of the traction electric drive in the low load conditions. The set objective is achieved by analogy with internal combustion engines by decreasing the consumed energy using the amplitude control of the three-phase voltage of the induction machine. The basis of the amplitude control is laid by the constancy criterion of the overload capacity with respect to the electromagnetic torque, which provides a reliable reserve from a "breakdown" of the induction machine mode in a wide range of speeds and loads. The control system of the traction electric drive contains a reference model of electromechanical energy conversion represented by the generalized equations of the instantaneous balance of the active and reactive power and the mechanical load. The induction machine is controlled by two adaptive variables: the electromagnetic torque and the voltage amplitude.

To evaluate the quality of a spark plug against the preignition, a new preignition simulator has been developed. The principle of this apparatus is to estimate the occurrence of preignition caused by a temperature rise in the electrode. The engine is operated with repeated stepwise shifting of spark timing by 55° CA advance from the MET condition. The number of advanced cycles is increased until the occurrence of real preignitions. By the number of advanced cycles when preignition occurs, the quality of the spark plug with respect to preignition can be evaluated. From this test result, it is confirmed that this preignition simulator is very useful for the practical application of experimental testing.