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The insulated-gate bipolar transistor (IGBT) is the most important part of a power converter. The heat generated during operation will cause the junction temperature of the IGBT to rise above ambient temperature. The junction temperature must stay within its predefined limit to ensure reliable operation. A properly designed cooling system is crucial for the overall operation, and an accurate prediction of power loss is critical in the design of a good thermal system. In this paper, a pulse-width modulation (PWM) full-bridge converter is designed for free-piston engine generators (FPEGs), and a low-cost forced-air cooling system is used for heat dissipation. For the converter to choose the IGBT module or discrete IGBT as the switching device, loss and thermal analyses are carried out. The loss analysis model of the converter is established, which considers the influence of the IGBT parasitic capacitance and gate driver voltage on the switching losses.

During the early phase of vehicle development, one of the key design attributes to consider is the inner comfort for occupants. Internal spaciousness is the pillar that is responsible for user's comfort and make into customer comfort needs in engineer metrics. Therefore, it is one of the key requirements to be considered during the vehicle design. Certain internal vehicle characteristics such as the size of shoulder room and the knee clearance are engineer metrics that influence the perception of comfort for occupants. One specific characteristic influencing satisfaction is the headroom, which is the subject of this paper. The objective of this project is to analyze the relationship between the vehicle headroom with the driver satisfaction under real world driving conditions, based on research, statistical data analysis and dynamic clinics. Other influences, such as the position of the driver in the seat was also studied and captured in this paper.

In vehicle design, the H point is a theoretical relative location measured in relation to specific characteristics, for example, H point to vehicle floor (H30), H point to ground (H5) and others. Based on theoretical H point automakers concept their vehicle and have to make important decisions on vehicle architectural that could result in a bad product for the future customers and during the early phase of vehicle development, one of the key design attributes to consider is in relation to the comfort of the user, so that its design and its components enable a favorable interaction with the occupant. Accessibility is one of the pillars on which this concern can be observed. Certain features such as the size of door opening and the height of the vehicle from the ground, among others, may influence the level of satisfaction of the occupants’ access.

During the early phase of vehicle development, one of the key design attributes to consider are the interior storages for occupants. Internal storage is the pillar that is responsible for user’s comfort and make into customer comfort needs in engineer metrics. Therefore, it is one of the key requirements to be considered during the vehicle design. The vehicle has some interior storages, like storages on door trim, floor console and IP and to define the best solution for the customer, engineering team has certain internal vehicle characteristics such as the volume and size of storage are engineer metrics that influence the perception of comfort for occupants. One specific characteristic influencing satisfaction is the glove box volume, which is the subject of this paper.

During the early phase of vehicle development, one of the key design attributes to consider is the inner comfort for occupants. Internal spaciousness is the pillar that is responsible for user’s comfort and make into customer comfort needs in engineer metrics. Therefore, it is one of the key requirements to be considered during the vehicle design. Certain internal vehicle characteristics such as the size of shoulder room and the knee clearance are engineer metrics that influence the occupants’ perception for comfort. One specific characteristic influencing satisfaction is the headroom, which is the subject of this paper. The objective of this project is to analyze the relationship between the second row’s vehicle headroom with the occupant’s satisfaction under real world driving conditions, based on research, statistical data analysis and dynamic clinics.

India has one of the highest growth rates of individual mobility in the world, as well as one of the largest numbers of road casualties. Modern active safety systems are slowly becoming established in the Indian passenger car market. The intension of this study is to investigate the effectiveness of the car safety feature Electronic Stability Control (ESC) for India. The Indian accidents has to be analysed to identify the reliable root cause. For this purpose, passenger car Loss of Control accidents were investigated in more detail with the aim of estimating the safety potential of ESC for India. A methodology is developed to extrapolate the in-depth accident database of Road Accident Sampling System for India (RASSI) to the entire accident situation in India. Loss of Control accidents are analysed with regard to their root causes, crash consequences and contributing factors.

The loss of preload in bolted joints is the main cause of quality problems, reworks or even joint failures during work. Several measurement methods are presented in the literature, but the difference of precision between each one or even the right criteria to select the most appropriate method for each project is not clearly defined. This study evaluated the differences between two of the main losses of preload measurements methods currently used in the market: clamp load through elongation measurement by ultrasonic method and checking torque method. For this, a load cell was used to measure the clamp load after the tightening torque and joint relaxation. Since the checking torque method is one of the most frequently used method of the torque auditing, it is also presented a torque x angle curve analysis for different torque points that are normally displayed by the measuring equipment.

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.