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The main assignment of Controlled Auto Ignition (CAI) operation range expansion is to reduce the burn rate or combustion noise at high load and to minimize misfire at low load. The potential of two principal EGR strategies is well known to initiate CAI in a wide range of operation map by using a variable train system: the Exhaust Port Recirculation (EPR) for higher part load and the Combustion Chamber Recirculation (CCR - also called Negative Valve Overlap) for lower part load. However the detailed comparison of the ignition phenomena with each EGR strategy has not been fully studied yet. In this paper, EPR and CCR were compared with same operational condition (engine speed and load). For the analysis, flame luminescence and Raman scattering method for optical measurement and STAR-CD (CD-adapco) for numerical simulation are used.

The usage of special heavy duty transmission fluids has proven their value over earlier use of engine oils in powershift transmissions. But due to continued demands by the earthmoving and construction industries for improved transmission performance and durability, the need for a significant increase in the quality of those transmission fluids became apparent. Thus, a specification for a new fluid, Type C-2, was developed. This paper discusses the new fluid specification in terms of its requirements, the procedures setup whereby the various companies of the oil industry may qualify their fluids, and the continuing program to evaluate the performance of approved Type C-2 fluids.

Fuel properties are a very important factor to reduce particulate matter (PM) and other emissions with diesel engines. Especially the effect of aromatic contents has been discussed, though details of the influence differ in different reports. In this study the mechanism of PM formation was investigated in a small direct injection diesel engine. The fuels tested were paraffinic hydrocarbons (C7∼C12) with different boiling points (98∼216 °C), and the blending of aromatic hydrocarbons (1∼4 rings) with paraffinic and olefinic hydrocarbons. The effect of the structure of fuels with the same carbon numbers (dodecane and dodecene) was also investigated. The results showed that the amount of SOF decreases to about one tenth of that of diesel oil when using low boiling point paraffinic hydrocarbons like heptane. However, the total amount of unburned hydrocarbon increases due to over-leaning of the mixture due to the early evaporation.

Deicing the aircraft using fluid, prior takeoff is mandatory; since a thin layer of ice or snow can compromise the safety. With the same idea, to use anti-icing fluid during a frozen precipitation to protect the aircraft is also essential. Commercialized anti-icing fluids all pass the process of qualification as described in the SAE documents. One of these documents specifies a set of tests that reproduce freezing precipitation to obtain endurance time and then the holdover timetables. The endurance time is determined by visual inspection: when 30% of the plate is covered with frozen contaminants. With the evolution of technology and the venue of new tools, it may simplify the process, and at least confirm the observations. This paper proposed a thermal and visual analysis of the behavior of a Type IV fluid subjected to light freezing rain. During the precipitation, the plate temperature is measured with thermocouples and recorded using a visual camera and an IR camera.

Fischer-Tropsch (FT) conversion of gasification products to liquid hydrocarbon fuel commonly includes FT synthesis followed by mild refining of the FT synthetic oil into diesel, kerosene, and naphtha, each defined by a specific boiling range. These FT products are derived typically by mixing condensable gaseous reactor effluent (∼C5-C20) with hydrocracked liquid reactor effluent (∼C20+). This mixture of FT liquids (FTL), is then hydrotreated and distilled to yield the desired products. This paper evaluates compression-ignition engine performance during preliminary tests of the condensable gaseous reactor effluent (∼C5-C20) portion of the (FTL) from a Syntroleum Corporation plant. Engine operability, maximum torque, fuel economy and emissions were evaluated for both FTL and mixtures of FTL with gasoline, hexanes, diethyl ether, and ethanol. Emphasis was placed on particulate and NOx emissions. However, hydrocarbon, carbon dioxide, and oxygen concentrations were also followed.

“Variable Valve Actuation” (VVA) refers to any method of opening and closing engine intake and exhaust valves in a way that can be varied during engine operation. This report considers purely mechanical means of producing variable valve actuation. In particular, we tabulate all types of planar mechanisms for converting a single rotational input (camshaft) into an oscillating poppet valve motion, up to 4 moving parts.

This paper introduces and develops the concept of “Type X” and “Type Y” errors in model validation and calibration, and their implications on extrapolative prediction. Type X error is non-detection of model bias because it is effectively hidden by the uncertainty in the experiments. Possible deleterious effects of Type X error can be avoided by mapping uncertainty into the model until it envelopes the potential model bias, but this likely assigns a larger uncertainty than is needed to account for the actual bias (Type Y error). A philosophy of Best Estimate + Uncertainty modeling and prediction is probably best supported by taking the conservative choice of guarding against Type X error while accepting the downside of incurring Type Y error. An associated methodology involving data- and model- conditioning is presented and tested on a simple but rich test problem.

The goal of this study was to use naturalistic driving data to characterize the longitudinal and lateral accelerations of vehicles making a left turn from a stop at signalized intersections. Left turn maneuvers at 15 intersections were extracted from the Second Strategic Highway Research Program (SHRP2) database. A subset of 420 traversals for lead vehicles that were initially stopped and negotiated their left turns unimpeded by oncoming traffic was used for the analysis. For each traversal, we extracted information regarding the driver’s sex and age, the vehicle type, the vehicle’s longitudinal and lateral acceleration, and on-board forward-facing video. From the video, we further extracted information about whether the road was dry/wet and if it was day/night, and from aerial photographs of the intersections we extracted the radius of each left turn path through the intersection.

The goal of this study was to use naturalistic driving data to characterize the motion of vehicles making right turns at signalized intersections. Right-turn maneuvers from 13 intersections were extracted from the Second Strategic Highway Research Program (SHRP2) database and categorized based on whether or not the vehicle came to a stop prior to making its turn. Out of the vehicles that did stop, those that were the first and second in line at the intersection were isolated. This resulted in 186 stopped first-in-line turns, 91 stopped second-in-line turns, and 353 no stop turns. Independent variables regarding the maneuver, including driver’s sex and age, vehicle type, speed, and longitudinal and lateral acceleration were extracted. The on-board video was reviewed to categorize the road as dry/wet and if it was day/night. Aerial photographs of the intersections were obtained, and the inner radius of the curve was measured using the curb as a reference.

Telescopic and articulated aerial devices must have reliable controls. This paper describes several types in use today, together with comments on the selection of hydraulic fluids for use in this kind of equipment.

THIS paper points out that, with the solid-injection Diesel-engine, the reliable smooth-combustion performance of the old air-injection type has not been duplicated, especially so with the high-speed Diesel-engine. To get the specific output as high as possible, and to obtain good fuel-economy, it is necessary to have the first part of the combustion approaching the constant-volume cycle, while the rest of the combustion is rather slow. In other words, the rate of burning is a maximum at the beginning and decreases toward the end of the combustion. The rate of burning in a gasoline engine is slow at the beginning and becomes a maximum at the end of the combustion, neglecting the slight after-burning. Comparison is made between the rate of burning of different types of high-speed Diesel-engines and the rate of burning of the gasoline engine.

Measurements of lightning-induced transients in typical electrical circuits installed within a small, conventional aluminum airplane fuselage have been made as part of a comprehensive assessment of the effects of direct lightning strikes and high intensity radiated frequency (HIRF) fields on avionic systems installed within small aircraft. These measurements were conducted in support of development of design guidelines for installation and certification of advanced avionics in small aircraft, under a U.S. National Aeronautics and Space Administration (NASA) sponsored Small Business Innovation Research (SBIR) program aimed at developing technology to enable advanced avionic systems to be installed in new small airplanes or to be retrofitted into existing airplanes. This paper presents examples and summaries of lightning-related magnetic fields and resulting induced voltage and current transients within a small 4-place Mooney aluminum fuselage and engine nacelle.

In China, nearly 25% of traffic fatalities are pedestrians. To avoid those fatalities in the future, rapid development of countermeasures within both passive and active safety is under way, one of which is autonomous braking to avoid pedestrian crashes. The objective of this work was to describe typical accident scenarios for pedestrian accidents in China. In-depth accident analysis was conducted to support development of test procedures for assessing Autonomous Emergency Braking (AEB) systems. Beyond that, this study also aims for estimating the mitigation of potential crash severity by AEB systems. The China In-depth Accident Study (CIDAS) database was searched from 2011 to 2014 for pedestrian accidents. A total of 358 pedestrian accidents were collected from the on-site in-depth investigation in the first phase of CIDAS project (2011-2014).

Many parameter values are needed for mathematical models which describe the dynamic motions of a vehicle on the road. These include mass and inertia parameters, suspension geometry factors, suspension compliances, damping properties, and tire properties. This paper is based on many suspension parameter, inertia parameter, directional response and tire tests. It defines the ranges of these parameters that are encountered in production vehicles. It briefly discusses some of the combinations of these factors that are designed into production vehicles. Some general rules for estimating certain of these parameters are stated.

This paper presents typical flow structures around a 60%-scale wind-tunnel model of a Formula One (F1) car, using planar particle image velocimetry (PIV). The customized PIV system is permanently installed in a wind tunnel to help aerodynamicists in the development loop. The PIV results enhance the understanding of the mean velocity field in the two-dimensional plane in some important areas of the car, such as the front-wheel wake and the underfloor flow. These real phenomena obtained in the wind tunnel also help maintain the accuracy of simulations using computational fluid dynamics (CFD) by allowing regular checking of the correlation with the real-world counterpart. This paper first surveys recent literature on unique flow structures around the rotating exposed wheel, mostly that on the isolated wheel, and then gives the background to F1 aerodynamics in the late 2000s.

One of the factor which determine vehicle ride quality is the waviness of the road surface. A series of power spectral density measurements has been done on several road types in West Java, that is Macadam, Nacas, Coldmix Buton Asphalt and Hotmix Buton Asphalt. The measurement were carried out by means of fifth wheel and the data were digitally analysed using Spectrum Analyser and Desktop Computer, The results would be very useful for the development of vehicle design, and for the construction of the road itself.

Tyre force and moment properties are one of the fundamental properties for tyre vehicle stability. This paper reports the effect of tyre design variables on force and moment properties. Four popular sizes of the Indian car tyre have been taken in this study which outlines the effect of construction, aspect ratio, and other variables like belt angle etc. It has been noticed that radial tyre generates higher force and moments vis-a-vis a bias tyre. With decrease in aspect ratio, the force proportionally increases improving the cornering stability at high speed. The study also shows that a tyre having higher stiffness shows higher cornering force. Thus this paper projects the significance of tyre force and moment properties for total vehicle control.

The purpose of this paper is to present a concept of Hydro-Pneumatic Interconnected Suspension (HPIS) and investigate the unique property of the zero warp suspension stiffness. Due to the decoupling of warp mode from other modes, the road holding ability of the vehicle is maximized meanwhile the roll stability and ride comfort can be tuned independently and optimally without compromise. Ride comfort can be improved with reduced bounce stiffness and the progressive air spring rate can reduce the requirement of suspension deflection space. The roll stability can also be improved by increased roll stiffness. Vehicle suspension system modelling and modal analysis are carried out and compared with conventional suspension. The frequency response of tyres' dynamic load reveals that the proposed zero-warp-stiffness suspension enables the free articulation of front and rear axles at low frequency.