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The viscous coupling is known mainly as a driveline component in four wheel drive vehicles. Developments in recent years, however, point toward the probability that this device will become a major player in mainstream front-wheel drive application. Production applications in European and Japanese front-wheel drive cars have demonstrated that viscous couplings provide substantial improvements not only in traction on slippery surfaces but also in handling and stability even under normal driving conditions. This paper presents a series of proving ground tests which investigate the effects of a viscous coupling in a front-wheel drive vehicle on traction and handling. Testing demonstrates substantial traction improvements while only slightly influencing steering torque. Factors affecting this steering torque in front -wheel drive vehicles during straight line driving are described.

This study looked into the application of active thermal coatings on the surfaces of the combustion chamber as a method of improving the thermal efficiency of internal combustion engines. The active thermal coating was applied to a production aluminium piston and its performance was compared against a reference aluminium piston on a single-cylinder diesel engine. The two pistons were tested over a wide range of speed/load conditions and the effects of EGR and combustion phasing on engine performance and tailpipe emissions were also investigated. A detailed energy balance approach was employed to study the thermal behaviour of the active thermal coating. In general, improvements in indicated specific fuel consumption were not statistically significant for the coated piston over the whole test matrix. Mean exhaust temperature showed a marginal increase with the coated piston of up to 6 °C.

Diesel exhaust particulate samples were collected upstream and downstream of an alumina coated metal wool filter mounted in the exhaust system of a 1600 CC Volkswagen engine being operated at idle, 30 MPH and 50 MPH. Dichloromethane extraction of the particulates collected indicates that the filter decreased the amount of soluble organics bound to them. The extracts were subjected to Ames tests. Statistical analysis of the results indicates that on a per ug of extract basis the filter decreased the mutagenic activity of the organics adsorbed to the downstream particles collected at 30 MPH and increased the mutagenic activity of downstream particles collected at idle. Results do not allow a conclusion regarding the effect of the filter on the mutagenic activity of particles collected at 50 MPH. The net effect of the filter on diesel emissions is potentially beneficial.

An external injection system was introduced to control the lean Nox trap(LNT). LNT absorbs Nox in lean condition of exhaust gas and discharges N2 by reducing Nox in rich condition. To make exhaust gas lean or rich, fuel injection into the exhaust gas is used with the engine control. There are two ways to add a reducing agent into exhaust gas. One is post injection using common rail system and the other is external injection. The external injection has prior benefit; can be controlled independently without disturbing engine control, can be adapted to various layout of exhaust system, has no oil dilution problem, and etc. In this study the effect of an external fuel injection on the control of LNT system was investigated. At first, the injection characteristic of the external injection was analyzed: flow rate and atomization characteristic was controlled by the PWM signal and the fuel pressure. Then the external injection system was introduced into NPRS(Nox PM Reduction System).

A diesel engine particulate emission rate can be 7 times greater when it is cold than when it is warm. It is recognized within the automotive industry that any catalyst, either diesel or gasoline, is unable to function efficiently when it is cold. The two way oxidation diesel catalyst is unable to oxidize CO to CO2 and unburned hydrocarbons (uHCs) to CO2 and H2O, due to low start up exhaust temperatures. Add to this the inherently lower temperature of diesel exhaust, and it is possible that during urban driving the catalyst can take up to 10 minutes before receiving sufficient energy to start oxidizing the exhaust efficiently. Work carried out at the University of Central England (UCE) suggests that although the catalyst is unable to oxidize CO and uHCs emissions during start and warm up, it has a secondary function of trapping the particulates produced, and reduce the tailpipe particulate emissions during the engine warm up phase.

A diesel oxidation catalyst (Engelhard PTX Series) was evaluated on a medium-duty diesel engine (Caterpillar 3208, naturally aspirated, direct injection). Tests were conducted at six modes of the EPA 13 mode heavy-duty cycle to measure the total particulate, soluble organic fraction (SOF), sulfates, NO, NO2, NOx and hydrocarbons emitted by the engine with and without the oxidation catalysts. Chemical analysis of the SOF collected was carried out to determine the effects of the catalysts on each of the subfractions composing the SOF. The Ames Salmonella/microsome bioassay was employed to quantify the mutagenic properties of the particulate SOF. Test results show large increases in the amounts of total particulate and sulfate emissions due to the catalyst while the amounts of SOF are reduced by the catalyst. The amounts of NOx produced with and without the catalyst are similar, but the equivalent NO2 emitted with the catalyst installed is increased at most modes.

The components of the piston/ring/liner system must have their wear resistance increased to meet the new engine requirements. The engine operating conditions can be even worse if corrosive wear in the engine is expected to occur. This paper presents a study to improve the wear resistance of piston ring coatings and liner materials by the addition of chromium carbide and carbide forming alloying elements, respectively. The engine tests were run with high sulfur fuel (about 1.0 wt%) and lubricant with low total base number (TBN) with the objective of increasing the corrosive conditions. The results show the improvement of the ring coatings wear resistance with the increase of the chromium carbide content. The cylinder liner materials also presented lower wear rates when they had hard particles, mainly due to the addition of niobium, vanadium and titanium.

A mathematical method for determination of the heat transfer effectiveness of the air conditioning condenser accounting for the effect of the nonuniform cooling air flow distribution is presented. Using twelve typical two-dimensional air flow maldistribution models, the heat transfer effectiveness of the condenser is calculated. The deterioration of the thermal performance of the condenser due to the effect of the air flow nonuniformity is then determined. The effect of the air flow nonuniformity on the sizing of the condenser is discussed.

Results of a theoretical investigation on the effect of the two-dimensional nonuniformity of air flow through the evaporator of automobile air conditioning system on its thermal performance are presented. Twelve typical two-dimensional air flow maldistribution models of four basic groups are considered. Convection heat transfer coefficients on both flow sides are not considered to be constants. Refrigerant side pressure drop is included in this study. The thermal performance of the evaporator and its deterioration due to this effect are determined for various conditions. The detrimental effect of the air flow nonuniformity on the thermal performance of the evaporator is found to be significant for many typical applications.

Additive manufacturing has been a promising technique for producing sophisticated porous structures. The pore's architecture and infill density percentage can be easily controlled through additive manufacturing methods. This paper reports on development of sandwich-shape extruded cross sections with various architecture. These lightweight structures were prepared by employing additive manufacturing technology. In this study, three types of cross-sections with the same 2-D porosity were generated using particular techniques. a) The regular cross section of hexagonal honeycomb, b) the heterogeneous pore distribution of closed cell aluminum foam cross section obtained from image processing and c) linearly patterned topology optimized 2-D unit cell under compressive loading condition. The optimized unit cell morphology is obtained by using popular two-dimensional topology optimization code known as 99-line code, and by having the same volume fraction as the heterogeneous foam.

The performance of brake system is dependent on the interaction between brake pad and rotor at the friction interface. The mechanical properties of the brake rotor that is made of gray cast iron are directly influenced by composition and microstructure. The elasticity modulus and the damping capacity play a significant role on the propensity of the brake rotor to generate noise. Brake squeal propensity was studied by investigating the correlation between the microstructure of gray iron brake rotor and the carbon equivalent (CE). The gray iron samples were manufactured to have different microstructures by changing the carbon equivalent (C.E.). The squeal noise tests were performed with different C.E rotors. The test results show potential of the high carbon composite rotor material to reduce the squeal noise propensity. In order to understand the effect of rotor microstructure and composition on squeal, resonant frequencies and damping ratios were evaluated.

Propensity of cold judder was studied by investigating the correlation between the microstructure of gray iron brake disks and friction properties of commercial brake linings. Based on a brake disk for a mid-size passenger car, gray iron disks with 6 different microstructures were manufactured by changing the carbon equivalent (C.E.) and cooling speed in a commercial manufacturing facility. Graphite morphology of the gray iron changed proportionally according to the C.E. and cooling speeds, exhibiting longer graphite flakes with high C.E. at slow cooling speeds. After screening tests of 23 commercial brake linings, 4 different brake linings (two non-steel and two low-steel linings with high μ and low μ) were selected for parasitic drag tests. Results showed that the preferential disk wear was pronounced in the case of using low steel linings and the trend was marked with the disks containing short graphite flakes.

The influence of the small amounts (1-3%) of the additive di-tertiary butyl peroxide (DTBP) on the combustion event of Homogeneous Charge Compression Ignition (HCCI) engines was investigated using engine experiments, numerical modeling, and carbon-14 isotope tracing. DTBP was added to neat ethanol and diethyl ether (DEE) in ethanol fuel blends for a range of combustion timings and engine loads. The addition of DTBP to the fuel advanced combustion timing in each instance, with the DEE-in-ethanol mixture advancing more than the ethanol alone. A numerical model reproduced the experimental results. Carbon-14 isotope tracing showed that more ethanol burns to completion in DEE-in-ethanol blends with a DTBP additive when compared to results for DEE-in-ethanol without the additive. However, the addition of DTBP did not elongate the heat release in either case.

The introduction of zinc coated steels, multication pretreatments and cationic electrodeposition primers has led to improved automobile corrosion resistance. However, zinc phosphates over zinc coated steel are more sensitive to the electrodeposition process than are those over cold rolled steel. This paper is concerned with the dissolution of zinc phosphate pretreatments during electrodeposition. Dissolution was greater than expected, but did not appear to hurt the overall performance of the painted metal. A small amount of dissolution may even allow better anchoring of the E.D. coating. Dissolution was greater at higher voltages and under rupture conditions. There was a definite connection between rupture behavior (electrical discharge) and pretreatment dissolution. Due to their lower alkali solubility, Zn-Mn-Ni phosphate pretreatments were more resistant to attack during electrodeposition than conventional phosphates.

A mathematical method to determine the effectiveness of the engine radiator accounting for the effect of the two-dimensional nonuniform fluid flow distributions on both cooling air and engine coolant sides is presented. By using a successive substitution technique, a single equation with the temperature of the heat transfer wall as the unknown variable is obtained from the three heat transfer rate equations. The radiator heat transfer effectiveness and its deterioration due to the effect of the two-dimensional flow nonuniformity on both fluid sides have been calculated for several typical fluid flow distributions. The effect of the flow nonuniformity on the sizing of the engine radiator of automobile is discussed.

The longitudinal motion of the head, thorax and lumbar spine of two test subjects was measured in low-speed rear-end collisions in order to understand the effect of the head-to-head restraint distance (backset) on the occupant kinematics. The two test subjects were exposed to three rear-end impacts at two crash severities, nominal changes in velocity (ΔV) of 1.11 (low ΔV) and 2.22 m/s (high ΔV). The backset was hypothesized to be an independent variable that would affect the head and neck motion and was set at 0, 5 or 10 cm. The x and z-axis accelerations of the impacted vehicle and the anatomical x and z-axis accelerations of each test subjects’ upper thorax and L5-S1 region were measured and then transformed to an earth-based coordinate system. Head accelerations were measured at the mouth and these accelerations were transformed to an earth-based coordinate system at the head center of gravity (CG).

The main aim of this study is to investigate the effect of NO and NO2 on the combustion characteristics such as pressure development and combustion phasing in natural gas HCCI engine. A secondary aim is to demonstrate a method of obtaining a significant sensitizing effect on methane oxidation reaction from small amounts of NOx. Experiments were conducted using a rapid compression-expansion machine that was constructed from a single-cylinder diesel engine. First, the sensitizing effect of NO and NO2 on the HCCI combustion of natural gas was investigated in a case where NOx was uniformly mixed into a charge. Obtained results show that the auto-ignition timing is significantly advanced and an acute heat release is promoted by adding either NO or NO2.

In preparation of an analog of human head and neck, the reports by R. G. Snyder and others were noted which stated that initial position of the head and neck had a definite effect upon resulting response. An investigation was undertaken to attempt to quantitate this effect, as a part of a much larger study underway for several years. Thirteen human volunteer subjects ranging from the 5th to the 97th percentile in sitting height were exposed to -Gx impact acceleration at peak sled accelerations of 6G and 10G. Two angles of the neck relative to chair and two angles of the head relative to the neck for a total of four conditions were tested for each subject for the 2 peak acceleration levels giving a total of 104 experiments. Instrumentation consisted of 6 accelerometers and two-axis rate gyro at the posterior spinous process of the first thoracic vertebral body, 6 accelerometers at the mouth, and a two-axis rate gyro at the top of the head.

The rapid growth of information technology has the potential to affect many of the reasons why people drive. The Internet is arguably the most significant recent milestone in the growth of information technology. This paper examines the ways Internet communication might affect the travel experience by a) eliminating traditional reasons for personal travel, b) providing new reasons, c) changing the balance between personal and freight travel, and d) changing trip length distribution. Changes of the types listed could affect the product demand "mix" for electric, hybrid-electric and fuel cell vehicles being developed.

This paper seeks to examine the effect of distance of the gas injector from an inlet valve on the combustion process in a LPG fuelled SI engine under varied injection timing. Tests were conducted at an engine test stand, where the operating conditions of the engine were maintained stable. The tests were undertaken on an indirect injection spark ignition engine under partial load and at a constant speed. Holes in the inlet pipes were drilled in order to test for four variants of injection nozzle distance from the combustion chamber into which 4 mm diameter nozzles were successively mounted. Each given distance was measured along the symmetry axis of the inlet port, which represents a real path of the fuel-air mixture. The results show that the engine performance is affected more by the injector distance from the inlet valve than by varied LPG injection timing. Consequently, cycle-to-cycle variations of main combustion parameters and engine performance parameters were analyzed.