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THE post-war automobile has received generous attention from the feature-story and human-interest writers, but little from the practical engineers who will build these cars. To bring a more realistic viewpoint into the post-war car picture, Mr. Colwell interviewed 81 of the leading oil and automobile engineers of America. He has formed a weighted average of the combined opinions of all the engineers consulted. Briefly, these conclusions are: 1. Immediately after the war, 1942 models will be built. No new models will be on the market for at least 18 months. 2. Although oil companies hope that eventually only two grades of gasoline will satisfy all demands, it appears that immediately after the war, four grades will be marketed: aviation, of 100 and 100-plus octane; premium, of 85-87 octane; regular, of 75-77 octane; and third grade, of 70 octane. 3. Compression ratio will go up, although ratios above 8:1 are not foreseen for the immediate future. 4.

The application of homogeneous charge compression ignition in engines requires the limitation of high pressure rise rates at high loads and ignition timing control. Both effects can be influenced by the addition of water: The cooling effect based on its high latent heat of vaporization can be used to control ignition timing. Too early heat release at high compression ratios can be retarded towards TDC. Pressure rise rates can be reduced by inhomogeneous cooling and the dilution of the charge by steam. The paper discusses the effects of Diesel-water emulsions. The results are compared to the separate direct injection of fuel and water. The experiments were carried out on a rapid compression and expansion machine. Optical measurements were conducted using the shadowgraph technique in order to visualize spray penetration as well as combustion in the same cycle. A heat release analysis was performed on basis of the pressure indication. Gaseous emissions were electrochemically measured.

A combined, experimental and numerical program is presented. This work summarizes an internal research effort conducted at Southwest Research Institute. Meeting new, stringent emissions regulations for diesel engines requires a way to reduce NOx and soot emissions. Most emissions reduction strategies reduce one pollutant while increasing the other. Water injection is one of the few promising emissions reduction techniques with the potential to simultaneously reduce soot and NOx in diesel engines. While it is widely accepted that water reduces NOx via a thermal effect, the mechanisms behind the reduction of soot are not well understood. The water could reduce the soot via physical, thermal, or chemical effects. To aid in developing water injection strategies, this project's goal was to determine how water enters the soot formation chemistry.

The goal of this paper is to delineate recent experimental evidence that the presence of conforming surface wear groove tends to stabilize the vibration and noise response of aircraft brakes. This finding is consistent with an earlier theoretical study in which the contact between Carbon-Carbon (C/C) composite brake disks was assumed to be visco-elastic and through this assumption it was found that the existence of conforming grooves results in increasing dynamic stability of brake disk interaction. Therefore, the presumption of visco-elastic contact for C/C brakes seems to agree with the experimental observation in a subscale dynamometer. The present paper summarizes both theoretical analysis and the test results. In the tests C/C composites were heat treated for one hour at temperatures 1800°C and 2400°C, respectively. They were then subjected to frictional tests in a subscale aircraft brake dynamometer at 50 % relative humidity (RH) level.

Aluminum castings are widely used in transportation equipment because of their high strength to weight ratio, heat conductivity, and corrosion resistance. In the past, heat-treated steel and cast iron were used for engine parts that required wear resistance, but the demand for weight reduction has gradually increased, and nowadays most of the large parts that make up an engine are made with Aluminum. If the large aluminum casting parts requires wear resistance, the steel parts may be partially included. The method is to wrap it at the time of casting or to accurately press it in. However, in order to achieve functionality, it may be better to partially bond the steel. Therefore, for the purpose of bonding a wear-resistant steel to the cast aluminum AC4C alloy, the influence of the bonding conditions and the shape of the joint was investigated in this study.

Gas Metal Arc Welding (GMAW) is widely employed for joining relatively thick sheet steels in automotive body-in-white structures and frames. The GMAW process is very flexible for various joint geometries and has relatively high welding speed. However, fatigue failures can occur at welded joints subjected to various types of loads. Thus, vehicle design engineers need to understand the fatigue characteristics of welded joints produced by GMAW. Currently, automotive structures employ various advanced high strength steels (AHSS) such as dual-phase (DP) and transformation-induced plasticity (TRIP) steels to produce lighter vehicle structures with improved safety performance and fuel economy, and reduced harmful emissions. Relatively thick gages of AHSS are commonly joined to conventional high strength steels and/or mild steels using GMAW in current body-in-white structures and frames.

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.