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Cylinder air/fuel ratio distribution is an important factor affecting the economy, power, vibration, and emissions of an internal combustion engine. Currently, production automobiles utilize an exhaust gas sensor located in the main exhaust stream in order to regulate air/fuel mixtures. By measuring the oxygen content of the exhaust gas for each cylinder independently, the degree of air/fuel variation between cylinders can be determined. This information can be used to determine the mixture quality of specific cylinders. Knowing these variances can lead to design changes in the intake and exhaust manifolds as well as better control of fuel metering which will improve the output of the engine. This study was carried out using a 1991 3.8L Buick V-6 engine with customized exhaust manifolds utilizing exhaust gas oxygen sensors for each cylinder in addition to the sensor located in the main combined exhaust gas stream. Production level, ZrO2 sensors were used for this experimental study.

The Formula Lightning is an exciting part of GMI Engineering & Management Institute's motorsports program. This project is an excellent opportunity for students to apply and test their acquired classroom skills in practical applications. Competing in six race events annually, students are exposed to high caliber competitions in engineering design, combined with the thrill of racing. The Formula Lightning is a unique high-speed electric vehicle. Most of the challenging engineering tasks lie within the drive train design and battery system efficiency. Part of the battery system design and development includes a quick and reliable technique for exchanging battery packs under race conditions. Designed and built by GMI students, this project encompasses all fields of engineering giving experience with mechanical and electrical design as well as project management and marketing.

The design and composition of heat shields is becoming a major factor in the design of future automobiles. The optimization of heat insulation materials is crucial in keeping size, mass, and cost to a minimum. The purpose of this paper is to describe the testing of four different fibrous insulating materials simulating 150,000 miles of the Underbody heat shielding that a light duty truck may experience. The materials were tested before and after the thermal durability experiment to show the degraded conduction performance of each sample.

The push to meet or exceed the requirements for fuel efficiency and emissions over the past two decades has forced automotive manufacturers to build lighter and hotter running vehicles. The addition of emissions packages and the trend to lower ground clearances have compounded the problem of overheating critical components. Higher temperatures may adversely affect critical components of the automobile such as fuel lines and speedometer cables. These are often routed in close proximity to heat sources. The goal of GMI's heat transfer team was to develop an innovative insulation package to minimize the temperature of critical cylindrical components. The team designed and tested six different samples and evaluated them on the following criteria: thermal resistance, temperature rise, manufacturability, ease of installation, reliability, size and cost.

Today's cars are creating higher engine temperatures with the increased performance demands of the American public. As a result, interior temperatures in cars are escalating as well. In this study, an attempt was made to find an alternate material for the floorpan insulation. Consideration was given to cost, thermal resistance per area, heat transfer rate, and the contact coefficient for each material. It was also important to remember that the material needed not only stand up to high temperatures, but also could not emit odors that may be offensive to the driver or his passengers. Seven different thermal systems were designed, and tested, as possible alternatives to current shielding systems. The test procedures, along with numerical analysis, helped to determine which of the materials were most suitable for application in today's car.

The placement and design of heat shields is a critical step in the design of todays vehicles. Computer modeling of heat shield configurations can help to optimize shielding performance while minimizing their size and cost. In this paper an attempt was made to determine the most effective shielding arrangement between the exhaust system and the fuel tank. It has been determined through numerical experimentation that vehicles equipped with plastic fuel tanks should have tank shields installed as a first preference over exhaust shielding in most practical applications.

Currently automobile companies are facing some major problems in the area of heat management. Many components experience excessive heat build-up which result in high waranty costs and bring up safety related concerns. Presently manufacturers shield high temperature exhaust components with thin metalic heat shields. A major concern is the close proximity of the exhaust system to a variety of critical components. Such components include gas lines, gas tanks, oil lines and the floor pan. Three forms of ceramic based insulation were applied to the vehicle exhaust system for testing and evaluation, namely a fibrous blanket, a brush-on coating, and a moldable putty. The exhaust system, as well as some critical components, were thermocoupled for the three different insulations as well as for a baseline test of an uninsulated but mechanically shielded exhaust.