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INVOLUTE SPLINES enjoy three major advantages over their straight-sided counterparts: 1. New design concepts have given a more rational approach to clearances and errors. 2. Manufacturing is cheaper and more accurate. 3. Gaging is simpler. Thus, the involute spline standard of SAE and ASA continue to take precedence over the older straight-sided standards.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

This paper describes an investigation into the sound quality of passenger car and light truck closure sounds. The closure sound events that were studied included side doors, hoods, trunklids, sliding doors, tailgates, liftgates, and fuel filler doors. Binaural recordings were made of the closure sounds and presented to evaluators. Both paired comparison of preference and semantic differential techniques were used to subjectively quantify the sound quality of the acoustic events. Major psychoacoustic characteristics were identified, and objective measures were then derived that were correlated to the subjective evaluation results. Regression analysis was used to formulate models which can quantify customers perceptions of the sounds based on the objectively derived parameters. Many times it was found that the peak loudness level was a primary factor affecting the subjective impression of component quality.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.

As part of a general EGR system model, an adiabatic thermodynamic vacuum EGR valve actuator model was developed and validated. The long term goal of the work is improved system operation by correctly specifying and allocating EGR system component requirements.

The feasibility of using experimentally determined flow fields at intake valve closing, IVC, as initial conditions for computing the in-cylinder flow dynamics during the compression stroke is demonstrated by means of a computer simulation of the overall approach. A commercial CFD code, STAR-CD, was used for this purpose. The study involved two steps. First, in order to establish a basis for comparison, the in-cylinder flow field throughout the intake and compression strokes, from intake valve opening, IVO, to top dead center, TDC, was computed for a simple engine geometry. Second, experimental initial conditions were simulated by randomly selecting and perturbing a set of velocity vectors from the computed flow field at IVC.

Because it is common to attach plastic parts to other plastic, metal, or ceramic assemblies with mechanical fasteners that are often stronger and stiffer than the plastic with which they are mated, it is important to be able to predict the retention of the fastener in the polymeric component. The ability to predict this information allows engineers to more accurately estimate length of part service life. A study was initiated to understand the behavior of threaded fasteners in bosses molded from engineering thermoplastic resins. The study examined fastening dynamics during and after insertion of the fastener and the effects of friction on the subsequent performance of the resin. Tests were conducted at ambient temperatures over a range of torques and loads using several fixtures that were specially designed for the study. Materials evaluated include modified-polyphenylene ether (M-PPE), polyetherimide (PEI), polybutylene terephthalate (PBT), and polycarbonate (PC).

The recent development of TiAl-based alloys by the aerospace community has provided an excellent material alternative for hot components in automotive engines. The low density combined with an elevated temperature strength similar to that of Ni-base superalloys make TiAl-based alloys very attractive for exhaust valve applications. Lighter weight valvetrain components improve performance and permit the use of lower valve spring loads which reduce noise and friction and enhance fuel economy. However, difficult fabricability and a perception that TiAl alloys are high cost, low volume aerospace materials must be overcome in order to permit consideration for use in high-volume automotive applications. This paper provides a comparison of properties for several exhaust valve alternative materials. The density of TiAl alloys is lower than Ti alloys with creep and fatigue properties equivalent to IN-751, a current high performance exhaust valve material.

The salt spray test has been an industry wide standard corrosion test since its conception in 1914. A literary review of its history shows that it has· always been thought of as inconsistent and unreliable but, for a variety of reasons, has continued to be used. A study of more than 55 salt spray cabinets was performed using a controlled lot of parts and questionnaires on cabinet operation. Although the tested parts varied from mildly corroded to extremely rusted no factor could be found to account for the differences. Although the test has its uses it should be studied by an industry formed committee which should make recommendations as to further standardization and corrections to the test. A lengthy chronological bibliography aids the reader in further study and reference.

In this study, the particle emission characteristics of 10% alternative diesel fuel blends (Rapeseed Methyl Ester and Gas-to-Liquid) were investigated through the tests carried out on a light duty common-rail Euro 4 diesel engine. Under steady engine conditions, the study focused on particle number concentration and size distribution, to comply with the particle metrics of the European Emission Regulations (Regulation NO 715/2007, amended by 692/2008 and 595/2009). The non-volatile particle characteristics during the engine warming up were also investigated. They indicated that without any modification to the engine, adding selected alternative fuels, even at a low percentage, can result in a noticeable reduction of the total particle numbers; however, the number of nucleation mode particles can increase in certain cases.

Speciation of sulfurous acid, sulfuric acid and ammonium sulfate collected from the aerosol phase on a Fluoropore filter has been readily accomplished using techniques of chemical ionization mass spectrometry combined with thermal separation. Thermal separation of ammonium hydrogen sulfate from ammonium sulfate was not possible. Spectral separation of these species by selective ionization is proposed. Analysis of sulfate aerosols collected from ambient air and catalyzed vehicle emissions is described. It was found that sulfuric acid aerosol was rapidly converted to ammonium sulfate or ammonium hydrogen sulfate in the presence of ambient concentrations of ammonia. Ambient samples collected in the Detroit metropolitan area have been found to contain only trace quantities of sulfuric aicd. Sulfate samples collected from a dilution tube into which catalyzed vehicle exhaust was injected were found to contain significant quantities of ammonium sulfate in addition to sulfuric acid.

New European emissions legislation (Euro5) specifies a limit for Particle Number (PN) emissions and therefore drives measurement of PN during vehicle development and homologation. Concurrently, the use of biofuel is increasing in the marketplace, and Euro5 specifies that reference fuel must contain a bio-derived portion. Work was carried out to test the effect of fuels containing different levels of Fatty Acid Methyl Ester (FAME) on particle number, size, mass and composition. Measurements were conducted with a Cambustion Differential Mobility Spectrometer (DMS) to time-resolve sub-micron particles (5-1000nm), and a Horiba Solid Particle Counting System (SPCS) providing PN data from a Euro5-compliant measurement system. To ensure the findings are relevant to the modern automotive business, testing was carried out on a Euro4 compliant passenger car fitted with a high-pressure common-rail diesel engine and using standard homologation procedures.

The Ford PROCO stratified charge engine combines the desirable characteristics of premixed charge and Diesel engines. The outstanding characteristics of premixed charge engines are their high specific output, wide speed range, light weight and easy startability but they exhibit only modest fuel economy and relatively high exhaust emissions. The desirable characteristic of the Diesel engine is its outstanding fuel economy. However, the disadvantages of the Diesel, which include noisy operation, limited speed range, exhaust odor, smoke, hard startability, and particulate emissions have tended to limit their acceptance. In the gasoline fueled, PROCO stratified charge engine, direct cylinder fuel injection permits operation at overall lean mixture ratios and higher compression ratio. These features enable the PROCO engine to achieve brake specific fuel consumption values in the range of prechamber diesel engines.

The evolution and development of the automobile radio antenna is perhaps one of the most neglected success stories in the automotive industry. Born in the twilight of the last century, it evolved from a simple wire wrapped around a tree branch, to the current heated rear screen or backlite antenna. Part One (SAE No. 870090) described seven types of antennas in detail, covering the period 1897-1937. It was shown how the early radio engineers, struggling to develop a viable car antenna, had displayed a great degree of creativity and flexibility, from the “firecracker” experiments of Guglielmo Marconi in 1897, to the ingenious systems developed to overcome the problems created by the all-metal Turret-Top vehicles introduced by General Motors in 1934. In those pioneering days, the United States public was having a love affair with both the automobile and radio broadcasting, so it was no surprise that their marriage did not take long to arrive.

The effect of port injected small fuel droplets was evaluated for several different modes of engine operation. The droplets were generated by an Air Forced Injector (AFI), Figure 1, which uses high velocity air through a nozzle to produce fuel droplets on the order of 10mm Sauter Mean Diameter (SMD). AFI results were compared to those from a standard production pintle injector. Steady state data, “motored cold start” data, and injector cut-out data were collected. All three data sets illustrate functional advantages of AFI over standard Electronic Fuel Injection (EFI). Steady state testing showed that the AFI delivers complete freedom for specifying injection timing with respect to HC emissions. This freedom is highly advantageous for transient conditions because open valve injection with small droplets causes much less port wall wetting. Therefore, less control system compensation is necessary, and more accurate air-fuel ratio control is achievable.

A cylindrical combustion bomb with dynamic charging system and electro-hydraulic sampling valve is used to study the effects of turbulence on hydrocarbon (HC) emissions from a quench layer and from artificial crevices. The turbulence level is varied by changing the delay time between induction of combustible charge and ignition. Propane-air mixtures were studied over an initial pressure range of 150 to 500 kPa and equivalence ratios of 0.7 to 1.4. Sampling valve experiments show that quench-layer fuel hydrocarbons are extensively oxidized within 5 ms of flame arrival under laminar conditions and that turbulence further reduces the already low level. Upper limit estimates of the residual wall layer HC concentration show that residual quench layer hydrocarbons are only a small fraction of the exhaust HC emission.

Erosion damage to automotive car bodies caused by stones and small sand particles and road debris significantly affects the appearance of paint. Painted engineering plastics as well as precoated sheet steel are affected by erosion phenomenon. Erosion of painted plastic substrates results in cosmetic concerns while that on metal substrates results in cosmetic to perforation corrosion. This work describes a laboratory simulation of erosion of painted plastic substrates by small particles on various paint and substrate types. Gloss loss was used to quantitatively evaluate erosion of painted surfaces. Wear behavior of painted plastic substrates to slag sand impact was evaluated as a function of several variables including paint type (one-component melamine crosslinked (1K) vs. two-component isocyanate crosslinked (2K)), thermal history, and coating modulus. The effect of slag sand type (particle size and chemical composition) was studied.

Vehicle emissions have been measured and the results statistically evaluated for a vehicle test fleet consisting of four Escorts and four Explorers using both a fully formulated durability fuel doped with methylcyclopentadienyl manganese tricarbonyl (MMT) at 1/32 gram Mn/gallon and the same fully formulated durability fuel without the MMT. The fleet was divided in half -- half with MMT and half without MMT doped fuel. This report covers emission measurement results at 5,000; 15,000; 50,000 and 100,000 miles of exposure to MMT doped fuel. A modified paired t-test is used to analyze the emission data obtained from all the fleet vehicles. The statistical evaluation of both feedgas and tailpipe emissions indicate that the use of MMT is detrimental to emissions of HC at the 15,000 mile; 50,000 mile and 100,000 mile levels of MMT exposure. As mileage is accumulated, the pronounced the effect on HC by the fuel additive MMT.

A number of tests were conducted on a 2.5 litre, high-speed, direct-injection diesel engine running at various loads and speeds. The aim of the tests was to gain understanding which would lead to more effective use of exhaust gas recirculation (EGR) for controlling exhaust NOx whilst minimising the penalties of increased smoke emission and fuel consumption. In addition to exhaust emission measurements, in-cylinder sampling of combustion gases was carried out using a fast-acting, snatch-sampling valve. The results showed that the effectiveness of EGR was enhanced considerably by cooling the EGR. In addition to more effective NOx control, this measure also improved volumetric efficiency which assisted in the control of smoke emission and fuel consumption. This second of two papers on the use of EGR in diesel engines deals with the effects of EGR on soot emission and on the engine fuel economy.

A number of tests were conducted on a 2.5 litre, high-speed, direct-injection diesel engine running at various loads and speeds. The aim of the tests was to gain understanding which would lead to more effective use of exhaust gas recirculation (EGR) for controlling exhaust NOx. In addition to exhaust emission measurements, extensive in-cylinder sampling of combustion gases was carried out using a fast-acting, snatch-sampling valve. The results showed that the effectiveness of EGR in suppressing NOx was enhanced considerably by intercooling the inlet charge and by cooling the EGR. A companion paper (SAE 960841) deals with the effects of EGR on soot formation and emission [1].