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Since there is no universally applicable guideline or formula for welding design and fabrication, it is difficult to determine if the metallurgical properties of a finished weld will perform in accordance with engineering requirements. Consideration of all five major factors influencing the weldability of a structure - type of steel, material thickness, weld gaps or tolerance buildup, size of weld, and type of welding process - is the basis of the method for selecting appropriate steels and joint designs that is described in this paper. When used early in the design process along with such procedures as laboratory simulation, destructive testing, and metallurgical examination, it can prevent design and material changes from appearing at later, costlier stages of production.

THE author compares tread-wear of front and rear tires. Considering wear of rear tires as normal wear he analyses the abnormal wear observed on front tires and traces it to its causes, which are found to be camber, toe-in and imperfect geometrical layout of steering-arms and linkages. A theory of the scuffing action is developed. It is due partly to various rolling diameters at different parts of the tire tread and partly to the setting of the two front wheels so they tend to roll in slightly different directions. Reducing the camber angle to ¾ deg. and the toe-in to 1/16 in., reduces both these errors and results in longer tire-wear. No definite theory for camber is found. Toe-in depends on camber, counteracting the tendency of cambered wheels to diverge. A method is described for testing accuracy of rolling action by means of paper on a greased floor. Service stations must be put in a position to test and correct toe-in and camber.

Zinc dialkyldithiophosphates (ZDDPs) provide efficient and effective anti-wear, anti-oxidation and anti-corrosion properties in engine oil formulations. Two kinds of formulated engine oils were investigated including Oil 1 containing secondary ZDDPs, and Oil 2 containing primary/secondary ZDDPs. It revealed that different types of ZDDPs exhibits different volatilities and have different effects in the Sequence IIIG test. ZDDPs with higher molecular weight alcohols exhibit a relatively low volatility. The combination of primary/secondary ZDDPs exhibits higher phosphorus volatility in the Sequence IIIG, but have the same anti-wear protective behavior than that of the secondary ZDDPs in field tests. The field test results of phosphorus volatility and viscosity increase show encouraging agreement with the results of the Sequence IIIG test. However, the field test exhibits lower phosphorus volatility than the Sequence IIIG engine test.

The growth of coated sheet steels in automotive applications continues to require new application technology in joining, finishing, painting and forming. The formability of zinc-coated steels depends on both the character of the substrate and nature of the coating. By eliminating the substrate as a variable in this study, the effect of various coatings (one-side electrogalvanized, hot-dip zinc and iron-zinc alloy) on formability was determined using simulative laboratory tests. Under conditions of plane strain and stretch, all coated and uncoated steels performed comparably and can be considered interchangeable with each other. However, for drawing conditions, the drawability parameter, rm, of the hot-dip iron-zinc alloy coated steels was inferior to that of both free zinc coatings and uncoated steels.

A problem for the diesel engine that remains since its invention is injection nozzle hole fouling. More advanced injection systems and more complex fuels, now also including bio-components, have made the problem more intricate. Zinc and biodiesel have often been accused of being a big part of the problem, but is this really the case? In this study, nozzle fouling experiments were performed on a single cylinder engine. The experiments were divided in three parts, the first part studied the influence of zinc neodecanoate concentration on nozzle hole fouling, the second part studied the effect of neodecanoates of zinc, sodium, calcium, copper, and iron on fuel flow loss and in the last part it was examined how RME concentration in zinc neodecanoate contaminated petroleum diesel affected nozzle hole fouling propensity. After completed experiments, the nozzles were cut open and the deposits were analyzed in SEM and with EDX.

Exhaust emissions were characterized from a Cummins LTA10 heavy-duty diesel engine operated at two EPA steady-state modes with and without an uncatalyzed Corning ceramic particulate trap. The regulated emissions of nitrogen oxides (NOx), hydrocarbons (HC), and total particulate matter (TPM) and its components as well as the unregulated emissions of PAH, nitro-PAH, mutagenic activity and particle size distributions were measured. The consistently significant effects of the trap on regulated emissions included reductions of TPM and TPM-associated components. There were no changes in NOx and HC were reduced only at one operating condition. Particle size distribution measurements showed that nuclei-mode particles were formed downstream of the trap, which effectively removed accumulation-mode particles. All of the mutagenicity was direct-acting and the mutagenic activity of the XOC was approximately equivalent to that of the SOF without the trap.

A study of the Corning ceramic diesel particulate trap was conducted to investigate the trap's overall effect on diesel particulate fractions (soluble organic fraction. SOF; solid fraction, SOL; and sulfate fraction. SO4) under four different engine loads at 1680 rpm. The trap was found to filter the SOL fraction most efficiently with the SOF and SO4 fraction following in respective order. The filter efficiency of all fractions increased with increasing engine load. Graphs illustrating filter efficiency versus engine load indicate the slope of the SOF filter efficiency was smaller in magnitude than the TPM and SOL and SO4, fractions, which had similar slopes. The different slope of the SOF filter efficiency indicates other influences may be involved with the reduction in the SOF through the trap. Particle size distribution measurements in diluted exhaust revealed particle formation downstream of the trap.

This paper presents the test results of a research on the use of a detergent additive in gasoline. The main objective was to find out the additive effect on carburettor cleanliness and gasoline consumption. To show this additive effect, three pairs of vehicles of different makes and types were subjected to controlled test on the roads in a fixed route and on the chassis dynamometer at two different constant speeds. Additional tests on a monocylinder engine, each time kept in the same operational conditions for comparison tests, were conducted to show the additive effect in a thermodynamic sense (if there are any). The test distance travelled by each vehicle during the whole test was approx. 10,300 KM The average time needed was approx. 314 hrs. with an average speed of approx. 33 KM/hr. The average fuel consumption for each vehicle was approximately 1,170 litre, while the average fuel saving was approximately 7%. The monocylinder test results were impartial.

The effect of a Johnson Matthey catalyzed continuously regenerating technology™ (CCRT®) filter on the particle size distribution in the raw exhaust from a 2002 Cummins ISM-2002 heavy duty diesel engine (HDDE) is reported at four loads. A CCRT® (henceforth called DOC-CPF) has a diesel oxidation catalyst (DOC) upstream (UP) of a catalyzed particulate filter (CPF). The particle size data were taken at three locations of UP DOC, downstream (DN) DOC and DN CPF in the raw exhaust in order to study the individual effect of the DOC and the CPF of the DOC-CPF on the particle size distribution. The four loads of 20, 40, 60 and 75% loads at rated speed were chosen for this study. Emissions measurements were made in the raw exhaust chosen to study the effect of nitrogen dioxide and temperature on particulate matter (PM) oxidation in the CPF at different engine conditions, exhaust and carbonaceous particulate matter (CPM) flow rates.

The objective of this research was to study the effects of a CCRT®, henceforth called Diesel Oxidation Catalyst - Catalyzed Particulate Filter (DOC-CPF) system on particulate and gaseous emissions from a heavy-duty diesel engine (HDDE) operated at Modes 11 and 9 of the old Environmental Protection Agency (EPA) 13-mode test cycle Emissions characterized included: total particulate matter (TPM) and components of carbonaceous solids (SOL), soluble organic fraction (SOF) and sulfates (SO4); vapor phase organics (XOC); gaseous emissions of total hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), nitric oxide (NO) and nitrogen dioxide (NO2), oxygen (O2) and carbon dioxide (CO2); and particle size distributions at normal dilution ratio (NDR) and higher dilution ratio (HDR). Significant reductions were observed for TPM and SOL (>90%), SOF (>80%) and XOC (>70%) across the DOC-CPF at both modes.

In a ten car fleet test, the amount and chemical composition of intake valve deposits (IVD) and combustion chamber deposits (CCD) were determined. Five car makes, three driving cycles, and a gasoline with and without an IVD reducing additive were used. The amount of IVD and CCD were a strong function of car make, and the additive decreased IVD and increased CCD compared with non-additized base gasoline. The chemical changes in the composition of the CCD show that the additive was the source of the increased CCD. For all vehicles tested, a modified AMA Driving Cycle and a BMW Driving Cycle produced similar amounts of IVD and CCD, with similar chemical compositions. In contrast, the high speed cycle produced less CCD and gave CCD and IVD that had a different chemical composition than that of the other two driving cycles. No CCDI (combustion chamber deposit interference) and no driveability problems occurred during the normal course of accumulating mileage.

Testing conducted has indicated that it is more advantageous to promote film condensation on the external surface of a serpentine style evaporator than dropwise condensation. Heat transfer performance is enhanced with film condensation as compared to dropwise condensation. The increase in heat transfer capacity associated with film condensation can be attributed mainly to the reduction of airside pressure loss through the coil. Testing has revealed that a surface treatment with hydrophilic (wetting) characteristics will promote film condensation.

Some automakers have been studying variable compression ratio (VCR) technology as one possible way of improving fuel economy. In previous studies, we have developed a VCR mechanism of a unique multiple-link configuration that achieves a piston stroke characterized by semi-sinusoidal oscillation and lower piston acceleration at top dead center than on conventional mechanisms. By controlling compression ratio with this multiple-link VCR mechanism so that it optimally matches any operating condition, the mechanism has demonstrated that both lower fuel consumption and higher output power are simultaneously possible. However, it has also been observed that fuel consumption does not reduce further once the compression ratio reached a certain level. This study focused on the fact that the piston-stroke characteristic obtained with the multiple-link mechanism is suitable to a longer stroke.

The importance of using a moving floor to simulate the flow around a passenger car in a wind tunnel is considered. Measurements on a typical l/3rd scale car at normal ground clearance show that floor movement reduces drag by about 8% and reduces lift by nearly 30%. The effect on lift is more pronounced when the vehicle is yawed to the flow. Experiments on an idealised car shape show that there is a marked effect of floor movement if the underbody has rear upsweep. However in the near wake of a flat-based version of that model, with a straight underbody throughout, detailed velocity surveys show surprisingly little effect of floor movement. On the other hand, measurements of the structure of the wakes of a fixed wheel on a stationary floor and a rotating wheel on a moving floor show a large effect of floor movement.

Particle emissions have been generally associated to diesel engines. However, spark-ignition direct injection (SI-DI) engines have been observed to produce notable amounts of particulate matter as well. The upcoming Euro 6 legislation for passenger cars (effective in 2014, stricter limit in 2017) will further limit the particulate emissions from SI engines by introducing a particle number emission (PN) limit, and it is not probable that the SI-DI engines are able to meet this limit without resorting to additional aftertreatment systems. In this study, the solid particle emissions of a SI-DI passenger car with and without an installed Particle Oxidation Catalyst (POC®) were studied over the New European Driving Cycle (NEDC) on a chassis dynamometer and over real transient acceleration situations on road. It was observed that a considerable portion of particle number emissions occurred during the transient acceleration phases of the cycle.

In the wind tunnel the effect of a wind input on the aerodynamic characteristics of any road vehicle is simulated by yawing the vehicle. This represents a wind input where the wind velocity is constant with height above the ground. In reality the natural wind is a boundary layer flow and is sheared so that the wind velocity will vary with height. A CFD simulation has been conducted to compare the aerodynamic characteristics of a DrivAer model, in fastback and squareback form, subject to a crosswind flow, with and without shear. The yaw simulation has been carried out at a yaw angle of 10° and with one shear flow exponent. It is shown that the car experiences almost identical forces and moments in the two cases when the mass flow in the crosswind over the height of the car is similar. Load distributions are presented for the two cases. The implications for wind averaged drag are discussed.

This work investigates the effect of a three-way catalytic converter and sampling dilution ratio on nano-scale exhaust particulate matter emissions from a gasoline direct-injection engine during cold-start and warm-up transients. Experimental results are presented from a four cylinder in-line, four stroke, wall-guided direct-injection, turbo-charged and inter-cooled 1.6 litre gasoline engine. A fast-response particulate spectrometer for exhaust nano-particle measurement up to 1000 nm was utilised. It was observed that the three-way catalytic converter had a significant effect on particle number density, reducing the total particle number by up to 65 % over the duration of the cold-start test. The greatest change in particle number density occurred for particles less than 23 nm diameter, with reductions of up to 95 % being observed, whilst the number density for particles above 50 nm diameter exhibited a significant increase.

This study looks at the application of a titanium dioxide (TiO2) catalytic nanoparticle suspension to the surface of the combustion chamber as a coating, as well as the addition of hydrogen gas to a four-stroke spark-ignited carbureted engine as a possible technique for lowering engine-out emissions. The experiments were conducted on two identical Generac gasoline powered generators using two, four and six halogen work lamps to load the engine. One generator was used as a control and the second had key components of the combustion chamber coated with the catalytic suspension. In addition to the coating, both engines were fed a hydrogen and oxygen gas mixture and tested at low, medium and high loads. Using an unmodified engine as a control set, the following three conditions were tested and compared: addition of hydrogen only, addition of coating only, and addition of hydrogen to the coated engine.

The need for fuel conservation has caused increased interest in the rolling resistance and fuel consumption of tires. A study to determine the effect of the tire's fabric reinforcing system, both belt and carcass, on rolling resistance and fuel consumption is described and its results are presented.

Extensive efforts are being made to improve emissions from 2-stroke diesel engines. These improvements are primarily directed towards older model year engines with relatively high emissions compared with modern diesel engines. While most researchers focus their attention on engine design changes that promise substantial emission improvements, this work dealt with the turbocharger characteristics, especially as related to using internal coatings on both the compressor and turbine housings. Two identical turbochargers were tested on a Detroit Diesel 6V-92TA engine. One of the two turbochargers was left in its production configuration while the other was coated with a clearance control coating on the inside of the compressor and turbine housings. This coating led to a significant reduction in the tip clearance of both the compressor and turbine wheels.