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The maximum axial penetration distance of liquid phase fuel (i.e., the “liquid length”) in an evaporating diesel spray was investigated over a wide range of conditions using Mie-scattered light imaging. The parameters varied in the investigation included: the injection pressure, the orifice diameter and aspect ratio, the ambient gas temperature and density, and the fuel volatility and temperature. The experiments were conducted in a constant-volume combustion vessel with extensive optical access. Fuels were injected with an electronically controlled, common-rail diesel fuel injector. The dominant trends observed were: (a) Liquid length decreases linearly with orifice diameter and approaches zero as the orifice diameter approaches zero. (b) Injection pressure has no significant effect on liquid length. (c) Liquid length decreases with increasing ambient gas density or temperature, but with a declining sensitivity to each one as they increase.

During summertime, some in-vehicle components can reach very high temperatures, in particular because of solar radiation through windows. The liquid-filled double glazing (LFDGW) window permit the solar gain because of its absorbing properties and consequently permit to maintain the window temperature. The impact of such a window on in-vehicle temperatures is evaluated with the Therm_Cab® software. Results indicate that the temperatures of the in-vehicle component are reduced significantly.

A body of listening test techniques which produces consistant rankings of sound systems is presented. Sufficient detail is generated in the course of the prescribed listening evaluation to direct engineering changes to the system. A two dimensional weighting system (performance and usage) is used to determine a single-number rating.

The 1990's have witnessed widespread proliferation of inexpensive, inertia-loaded chassis dynamometers. Previously, chassis dynos were not accessible to the general public. Thanks to this proliferation, there is now a core audience of knowledgeable auto enthusiasts who have chassis dyno results for their cars, but little understanding of the difference between these results, SAE net HP and actual power delivered to ground. This audience consists of trend leaders and early adopters, the customers most sought after by the OEMs. This paper derives the loss sources present in these tests, and illustrates the difference between the different reference frames for power measurement.

Literate and illiterate drivers were compared on the basis of their driving histories and characteristics of their crashes. Illiterate drivers had significantly more crashes and convictions than the general driving public. When compared to matched control drivers, illiterate drivers still had more convictions and crashes. Their crashes tended to be in older vehicles that were more likely to have reported defects. They were also more likely to be driving trucks. Recommendations are presented for a comprehensive coordinated approach to encouraging acquisition of literacy skills which in turn may be reflected in improved driving performance.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

A literature and experimental study was done to create an overview of the behavior of gasoline combusted in a CI-engine. This paper creates a first overview of the work to be done before implementing this Gasoline Compression Ignition concept in a multi-cylinder engine. According to literature the gasoline blend will have advantages over diesel. First the shorter molecular chain of the gasoline makes it less prone to soot. Second the lower density gives the gasoline a higher nozzle exit speed resulting in better mixing capabilities. Third the lower density and higher volatility lets the spray length decrease. This lowers the chance of wall-impingement, but creates worse mixing conditions looking from a spray point of view. The CO and HC emissions tend to increase relative to operation with diesel fuel, NOx emissions largely depend on the choice of combustion strategy and could be influenced by the nitrogen bound to the EHN molecule that is used as an ignition improver.

The automotive industry has been witnessing a major shift towards downsized boosted direct injection engines due to diminishing petroleum reserves and increasingly stringent emission targets. Boosted engines operate at a high mean effective pressure (MEP), resulting in higher in-cylinder pressures and temperatures, effectively leading to increased possibility of abnormal combustion events like knock and pre-ignition. Therefore, the compression ratio and boost pressure in modern engines are restricted, which in-turn limits the engine efficiency and power. To mitigate conditions where the engine is prone to knocking, the engine control system uses spark retard and/or mixture enrichment, which decrease indicated work and increase specific fuel consumption. Several researchers have advocated water injection as an approach to replace or supplement existing knock mitigation techniques.

Hybrid Electric Vehicles (HEVs), Plug-in Hybrid Electric Vehicles (PHEVs), Extended Range Electric Vehicles (EREVs), Battery Electric Vehicles' (BEVs) development is gaining traction across all geographies to help meet ever increasing fuel economy regulations and as a pathway to offset concerns due to climate change and improve the overall green quotient of automobiles. These technologies have primarily shifted towards Li-ion batteries for Energy Storage (due to energy density and mass). In order to make actual business sense of these technologies, of which, battery is a major cost driver, it is necessary for these batteries to provide similar performance and life expectancy across the operating and soak (storage) range of the vehicles, as well as provide the requirements at a competitive cost.

Since they were first introduced in the early 1990's, lithium ion batteries have enjoyed unprecedented growth and success in the consumer marketplace. Combining excellent performance with affordability, they have become the product of choice for portable computers and cellular phones. Building on the same energy and life cycle attributes, which marked their consumer market success, but adding new high power storage capability, lithium ion technology is now poised to play a similar role in the transportation sector. With major programs in various aspects of electric and hybrid electric vehicles, Saft has developed a family of battery products which address the power and energy storage where light weight, long life, and excellent energy or power storage capabilities are needed. Significant progress in the packaging and control of high power, yet compact, batteries has been accomplished for a variety of vehicle applications.

Lithium-ion polymer battery has been widely used for vehicle onboard electric energy storage ranging from 12V SLI (Starting, Lighting, and Ignition), 48V mild hybrid electric, to 300V battery electric vehicle. Formulation on cell parameters acquired from minimum numbers of experiments, the modeling and simulation could be an effective approach in predicting battery performance, thermal effectiveness, and degradation. This paper describes the modeling, simulation, and validation of Lithium-Nickel-Manganese-Cobalt-Oxide (LiNiMnCoO2) based cell with 3.6V nominal voltage and 20Ah capacity. Constant current 20A, 40A, 60A, and 80A discharge tests are conducted in the computer-controlled cycler and temperature chamber. Discharging voltage curves and cell surface temperature distributions are recorded in each discharging test. A three-dimensional cell model is constructed in the COMSOL multi-physics platform based on the cell parameters.

The temperature monitoring of the lithium-ion battery is crucial for the advanced battery thermal management systems (BTMS) to improve performance and ensure operational safety and reliability of the battery system. In real applications, the core temperature of the battery is unfortunately unmeasurable due to the impracticality of placing a sensor inside the core, and has to be estimated online in real-time. Meanwhile, only the measurement of battery surface temperature can not meet the need for advanced BTMS due to the impact of the large temperature gradient between the surface and internal in high power applications. The battery core temperature estimation will become challenging when encountering sensor bias and noise.

Increased interest in global warming requires rapid improvements in CO2 reduction efforts. The automotive industry is placing high importance on CO2 reduction technologies. Using Lithium-ion (Li-ion) battery pack Stop & Start (S&S) system with combined energy regeneration is an effective technology to reduce CO2 emissions. Power supply storage is very important for the S&S system. High charging acceptance, low weight, and compact size are required. A Li-ion battery is the optimal power supply that meets these requirements. It has high charge acceptance per weight. Furthermore, we developed simple system structure which eliminates the need for the DC-DC converter. By utilizing a Li-ion battery that has voltage characteristics similar to the Pb battery there is no need for a converter to make adjustments between the two power supplies. The Li-ion battery's range of capacity must be managed appropriately as overcharge and overdischarge causes extensive damage to the battery.

Since entering the 21st century, the world has faced extremely serious environmental pollution and energy crises. In this context, new energy vehicles have been vigorously developed. Lithium-ion batteries have gradually become one of the most important energy sources for electric vehicles due to their excellent performance. State of charge (SOC) is one of the important indicators of the battery. Accurate estimation of SOC is of great significance to establishing a safe and accurate Battery management system (BMS). Among related methods for SOC estimation, observation-based methods have been widely used. However, this type of method has the disadvantages of being susceptible to disturbance and requiring high accuracy of the battery model. The traditional equivalent circuit model cannot meet the needs. This paper proposes a battery SOC estimation method based on LSSVM-UKF through research on lithium-ion battery modeling and SOC estimation methods.

Increasingly stringent requirements to improve fuel economy and reduce emissions are pushing the automotive industry toward more innovative solutions. To fulfill the demand, OEMs are developing hybrid systems with powerful electronics. The key technology is in all cases the battery. It is the most critical and expensive element of hybrid systems. The battery requires special care, as it must supply up to 400 Volts (V) and have a capacity of up to several kilowatt-hours (kWh). This paper will review the main functions of a Lithium-ion (Li-ion) battery management system, including power on/off, charging/discharging, and computation of the state of charge and state of health. In order to increase the battery lifespan, new functions such as active load balancing must be implemented.

A test was performed to investigate heat transfer and thermal conductivity from the intake valve centerline to the coolant passage. The study utilized 8 thermocouples in series in a live engine from warm-up to steady state over a complex load history, using various material choices.

For twenty years the dynamic test protocol for automotive safety research has been to use an anthropomorphic dummy in sled and crash test simulations. For the past four years, the author and associates have created and used a computer test protocol to model real world accidents and determine injury reduction from potential design modifications without some of the limitations and cost of the physical hardware and test procedure. The computer test protocol is described and examples of the research results in side and rollover accidents are detailed. Preliminary conclusions about injury reduction countermeasures and continuing research are suggested.

Driving simulators offer a safe alternative to on-road driving for the evaluation of driving performance. Standardized procedures for providing individualized feedback on driving performance are not readily available. The aim of this paper is to describe a methodology for developing standardized procedures that provide individualized feedback (“LiveMetrics”) from a simulated driving assessment used to measure driving performance. A preliminary evaluation is presented to test the performance of the LiveMetrics methodology. Three key performance indicators are used to evaluate the performance and utility of the method in the context of the preliminary evaluation. The results from the preliminary evaluation suggest abilities to customize reporting features for feedback and integrate these into existing driver training and education programs.

Australian vehicle standards are governed nationwide by the Australian Design Rules (ADR) that specify regulatory standards for the safety performance of road vehicles. The aim of this study was to quantify the number of lives saved on New South Wales roads by accelerating the update of safer vehicles by aligning ADR with global best practice represented by the new European Union General Safety Regulation. The methods used in this study to estimate the impact of future road safety interventions was a logical reduction of current crashes into future casualty outcomes, the residual, based on what is known about delivery of future safety measures and system improvements. A database was prepared including information on all 2018 fatalities on NSW roads (n=347). The database contained information for each individual crash, the vehicles and persons involved and the road environment where the crash occurred.