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The primary variable valve actuation strategies for diesel engines are variable late or early intake valve closing for control of effective compression ratio for Miller cycle and part-time HCCI, PCCI, or LTC; variable early exhaust valve opening for exhaust temperature control for after-treatment regeneration and improved engine transient response; on/off control of intake pre-bump and/or exhaust post-bump for IEGR and control of residual fraction; and on/off control of compression release and brake gas recirculation events for engine braking. Lost-motion hydraulic VVA is well suited to diesel engines due to the capability of on-off control of secondary events for IEGR and engine braking, high load capacity for early exhaust opening and engine braking, and inherent protection against valve-to-piston contact.

With the Elan's launch, Lotus is moving into a new era of low-volume production. By the middle of the next decade, a maximum of 3000 a year will be produced at Hethel and it was these requirements, combined with a desire for more design freedom, that led Lotus to carefully examine its current VARI (Vacuum Assisted Resin Injection) process and develop a unique, flexible system for the Elan. It was decided to develop a manufacturing process to employ a larger number of separate panels to allow future design freedom. The aim was to jig assemble panels which would allow accurate and consistent control of the complete assembly. Evaluation of alternative materials and processes for body panel manufacturing began in 1987, leading to the conclusion that the Lotus patented VARI process was still the most cost effective for the new car.

Loudness compensation is used in audio systems to compensate for the human ear’s reduced sensitivity to low-level, low frequency sounds. Volume controls in both home and automotive audio systems feature bass boost to preserve the listening experience as volume is reduced. Equal loudness contours from ISO226: 2003 suggest that at lower listening levels, as much as 30 dB of bass boost would be needed. In a vehicle, the essentially 1/F nature of cabin noise further suggests the need for bass content elevation. But loudness functions included in most vehicular systems today lack sufficient boost to meet either equal loudness requirements or vehicle noise compensation needs. This paper discusses the history of loudness compensation, shows samples of loudness characteristics used today and discusses a limited experiment that attempted to examine the subject’s loudness compensation settings that they preferred during blind testing.

The paper goes beyond the conventional way of looking at Loudness. We go into the calculation procedures taking into consideration two methods coming from the work of two researchers: Zwicker and Stevens. These methods are described in ISO 532. Instead of going to the traditional way of comparing the overall noises we penetrate in the calculation processes, step by step, getting subsidies to analyze the contributions of each frequency band. We applied the two methods using some random sound pressure spectra we generated. We are able to compare the total Loudnesses in both methods using a least-square fit with linear approximation. The spectra of contributions in sones in third-octave bands are also compared for both methods, through the development of simple mathematical expressions which are able to identify the parcel correspondent to each third-octave band.

Each automobile manufacturer has a different set of specifications for what turn out to he very similar car speakers. These specifications describe different teat procedures that yield substantially different results for the same loudspeaker driver. These test procedures will be compared and critiqued. A thorough analysis of the use of sine wave versus pink noise as a test signal will be given.

Spark ignition (SI) engines are susceptible to excess emissions at low ambient temperatures. Direct injection leads to the formation of particulate matter (PM), and direct injection spark ignition (DISI) engines should show greater PM emissions at low ambient temperatures. This study compares excess emissions of gaseous and solid pollutants following cold start at a low ambient temperature and the standard test temperature. Euro 5 passenger cars were tested on a chassis dynamometer within BOSMAL's climate-controlled test chamber, according to European Union legislation (−7°C over the urban driving cycle (UDC), and at 25°C). Two vehicles were also tested over the entire New European Driving Cycle (NEDC). Emissions of regulated compounds and carbon dioxide were analyzed; particulate emissions (both mass and number) were also measured, all using standard procedures.

Engine transient operation has attracted a lot of attention from researchers due to its high frequency of occurrence during daily vehicle operation. More emissions are expected compared to steady state operating conditions as a result of the turbo-lag problem. Ambient temperature has significant influences on engine transients especially at engine start. The effects of ambient temperature on engine-out emissions under the New European Driving Cycle (NEDC) are investigated in this study. The transient engine scenarios were carried out on a modern 3.0 L, V6 turbocharged common rail diesel engine fuelled with winter diesel in a cold cell within the different ambient temperature ranging between +20 °C and −7 °C. The engine with fuel, coolant, combustion air and lubricating oil were soaked and maintained at the desired test temperatures during the transient scenarios.

In 2020, CARB adopted the low NOX omnibus ruling, which provided revisions to on-road heavy duty engine compliance standards and certification practices. As part of the updates to the regulation, CARB has introduced a new in-use vehicle testing process that broadens the operation modes tested and considers the manufacturer’s intended vehicle application. Compared to the previous method, or the Not-to-Exceed approach, cold start and low ambient temperature provisions were included as part of the updates. The inclusion of low temperature operation requires the OEMs to design a robust engine and aftertreatment package that extends NOX conversion performance. The following work discusses the NOX emissions performance impact in a low temperature ambient environment. The engine and aftertreatment system evaluated was designed to comply with CARB’s low NOX regulations. The cycles tested included the CARB Southern NTE cycle and an FTP-LLC protocol.

Three low ash motor oils were compared to a conventional SE motor oil. The comparisons were made using the following test methods: laboratory dynamometer, road simulator, and Aunt Minnie short-trip test. The test results demonstrate that it may be possible with present technology to produce a motor oil approaching SE quality having 60-95% lower sulfated ash than most currently marketed SE performance level motor oils.

A gasoline particulate filter (GPF) is installed in a passenger vehicle for new exhaust regulation. However, ash in gasoline engine oil has a risk of clogging as well as performance decrease in the GPF. Therefore, new gasoline engine oil whose ash contents decrease to 0.8 mass% was developed in order to avoid the GPF clogging. In addition to this, our developed oil improves fuel efficiency (+0.2% from our SN 0W-16 fuel eco type oil) as well as anti-wear performance for gasoline engine, which resulted in meeting API SP/ILSAC GF-6 0W-16 official certification.

This paper is concerned with “low aspect ratio”* passenger car tires, the development and testing program prior to their acceptance for general use, and the overall characteristics of these tires from a vehicle manufacturer's standpoint. The paper presents a general review of the evolution of the pneumatic tire, and the importance of the tire/vehicle system approach in solving tire/wheel and chassis development problems. The paper also gives a brief report of the progress being made to establish uniform, industry-wide standards for tires, and for rim uniformity grading machines.

Preliminary back pressure and adsorption performance results are reported for two activated carbon honeycomb materials. The carbon impregnated honeycomb (CIH) material is porous ceramic honeycomb with a complete impregnation and coating of activated carbon on all ceramic surfaces. It offers the potential to be a permanent odor filter in that it can be in situ electrically regenerated. It has adsorption performance similar to commercially available layered filters, but has much lower back pressure. The second material is an activated carbon honeycomb (ACH) and is not ceramic-based as is CIH. As such, it has much more activated carbon and superior adsorption performance. The back pressure is low, as with CIH. It has significant potential as a high-performing disposable odor filter.

Distributive lighting systems utilizing high intensity discharge (HID) light sources and optical fiber light pipes are capable of delivering a large luminous flux to head lamp assemblies. The challenge is to design an efficient lamp package that angularly distributes this flux to meet legal and customer requirements for head lamp photometry performance. In this communication we: 1) review photometry guidelines which make the design of die low beam lamp package challenging, 2) outline the basic relationships between the optical design parameters, 3) illustrate solutions to the design optimization problem with three low beam head lamp design approaches, and 4) present photometry results and a computer rendered road simulation for prototype distributive lighting low beam head lamp hardware.

The purpose of this investigation is to evaluate the feasibility of rapeseed oil and palm oil for diesel fuel substitution in a naturally aspirated D.I. diesel engine, and also to find means to reduce the carbon deposit buildup in vegetable oil combustion. In the experiments, the engine performance, exhaust gas emissions, and carbon deposits were measured for a number of fuels: rapeseed oil, palm oil, methylester of rapeseed oil, and these fuels blended with ethanol or diesel fuel with different fuel temperatures. It was found that both of the vegetable oil fuels generated an acceptable engine performance and exhaust gas emission levels for short term operation, but they caused carbon deposit buildups and sticking of piston rings after extended operation.

This paper illustrates the results of an experimental study on the impact of a low cetane number (CN) oxygenated fuel on the combustion process and emissions of a light-duty (LD) single-cylinder research engine. In an earlier study, it was concluded that cyclic oxygenates consistently outperformed their straight and branched counterparts at equal oxygen content and with respect to lowering soot emissions. A clear correlation was reported linking soot and CN, with lower CN fuels leading to more favorable soot levels. It was concluded that a lower CN fuel, when realized by adding low reactive cyclic oxygenates to commercial diesel fuel, manifests in longer ignition delays and thus more premixing. Ultimately, a higher degree of premixing, in turn, was thought to suppress soot formation rates.

Small bore diesel engines often adopt a two-valve cylinder head and a non-central injector layout to expand the port flow passage area. This non-central injector layout causes asymmetrical gas flow and fuel distribution, resulting in worse heat losseses and a less homogenous fuel-air mixture than an equivalent four-valve cylinder head layout with a central injector. To improve these problems Toyota applied a new concept which was characterized by tapered shape design on the upper portion of the piston and low compression ratio to achieve more homogeneous gas flow and fuel-air mixture. This paper describes the impact of new combustion concept and the mechanism of the improvement by 3D-CFD analysis and optical measurement.

Automation in manufacturing is not a new idea. Automation remained simple until computers became available. The design, deployment, and utilization of cheap, simple automation became a lost art. We have begun to rediscover this art-“low cost automation,” or LCA, at NMMC. There is no textbook definition of LCA. One must consider LCA versus high-cost automation (HCA) from the perspective of the budget approval process, anticipated life cycle, complexity of control mechanism, and whether it is a general- or specific-purpose item. There isn't a specific dollar figure as a cutoff. HCA is a capital spending item. LCA shouldn't be. Low cost also refers to the life cycle maintenance costs of the item. HCA items may fill a wide variety of applications over a long life cycle. An LCA device at the end of its utilization cycle would be recycled for use in next-generation LCA applications. The true LCA device has a very simple guidance or control system, or even none at all.

This work treats of a project aiming the construction of a virtual panel of instruments of a general aviation aircraft. In addition, it could be applied the other vehicles as automobiles, trucks and ships. This work follows the tendency of recent researches of NASA for interfaces between pilot and aircraft that will permit to the general aviation community access to modern multifunctional displays that will become the piloting easier and safer. This work consists in developing software for acquisition and visualization and in specification of an analogical/digital conversion card and low cost sensors that will be used to measure the variables related to the movement of the aircraft.

With the development of start stop technology to improve fuel economy and to reduce carbon dioxide (CO2) emissions, the information of State of Charge (SOC) of the battery is highly desirable. Recent days the battery sensors are used in mid-segment and luxury automobiles that monitors the current, voltage and temperature of the battery and calculates the charge model and sends the information via CAN or LIN. These dedicated sensors are intended to perform various functions other than basic start stop. Hence these sensors are proven to be expensive for emerging market, which is intended to perform only basic start stop as the market is looking for a low cost solution. Bosch- India has developed and implemented a novel idea of bringing a low cost and reliable battery charge detection algorithm that can be realized within the Electronic Control Unit (ECU) without a dedicated sensor.

This paper reviews the technologies available for Bharat Stage 3 and 4 Heavy Duty on-highway emissions standards. Benchmarking data from several existing engines is used to explore the trade-offs between engine/vehicle cost and fuel consumption. Other implications of the available technologies, such as durability / reliability requirements, are also addressed. The paper provides recommendations for low cost approaches to meeting Bharat Stage 3 and 4 standards with good fuel consumption and reliability/ durability characteristics. A brief look ahead to future Bharat Stage 5 requirements is also provided.