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Six Sigma methodologies in combination with Lean thinking have made considerable inroads as continuous improvement tools initially in manufacturing and more recently for service and transactional processes. There is considerable interest globally in training professionals on the use and application of these tools appropriate to either operational or transactional areas. It has long been realized that adult learning is at its best when participants are involved in relevant “hands-on” experiments. Six Sigma training has seen the use of class room demonstrations ranging from the use of playing cards, simulations and to the use of sophisticated experiments to illustrate concepts of factorial designs. This paper will focus on a series of simple but modular experiments that were developed over the past two years illustrating the application of all the Statistical tools that are taught as a part of Six Sigma Green and Black Belt body of knowledge.

Two combined four-bar mechanisms have two functions: lift and collapse. In the current design, high effort was found for the collapse function. Axiomatic Design was used to analyze and optimize the current design. The customer domain was mapped into the functional domain by specifying customer needs in terms of functional requirements (FRs) and constraints (Cs). Design parameters (DPs) were identified in the physical domain for each functional requirement. Design matrices were then defined to characterize the product design. The two combined four-bar mechanisms have two functional requirements at the highest level: lift and collapse. The corresponding DPs are: lift four-bar linkage and collapse four-bar linkage. Through zigzagging to decompose to the next level, the design was found to be coupled. At this level, a torsion spring was selected as the DP for minimizing the lift effort.

High-dilution stratified EGR combustion system operating at stoichiometric air-fuel ratio (A/F) could offer significant fuel economy saving comparable to the lean burn or stratified charge direct injection SI engines, while still complies with stringent emission standards by using the conventional three-way catalytic converter. The most critical challenge is to keep substantial separation between EGR gas and air-fuel mixture, or to minimize the mixing between these two zones to an acceptable level for stable and complete combustion. Swirl-type stratified EGR and air-fuel flow structure is considered desirable for this purpose, because the circular engine cylinder tends to preserve the swirl motion and the axial piston movement has minimal effect on the flow structure swirling about the same axis. In this study, KIVA3V was used to simulate mixing and combustion processes in a typical pent-roof gasoline engine cylinder during compression and expansion strokes.

A low-pressure CO2-based climate-control system has the environmental benefits of CO2 refrigerant but avoids the extremely high pressures of the transcritical CO2 cycle. In the new cycle, a liquid “cofluid” is circulated in tandem with the CO2, with absorption and desorption of CO2 from solution replacing condensation/gas cooling and evaporation of pure CO2. This work compares the theoretical performance of the cycle using two candidate cofluids: N-methyl-2-pyrrolidone and acetone. The optimal coefficient of performance (COP) and refrigeration capacity are discussed in terms of characteristics of the CO2-cofluid mixture. Thermodynamic functions are determined either from an activity coefficient model or using the Soave equation of state, with close agreement between the two approaches. Reductions in COP due to nonideal compressor and heat exchangers are also estimated.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide in this cycle is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is revisited1, 2. The working fluid is a mixture of CO2 and a non-volatile liquid, referred to as a co-fluid, in which CO2 is highly soluble and readily absorbed and desorbed.

A design framework based on the principles of lean manufacturing and axiomatic design was used as a guideline for designing an automotive component manufacturing system. A brief overview of this design decomposition is given to review its structure and usefulness. Examples are examined to demonstrate how this design framework was applied to the design of a gear manufacturing system. These examples demonstrate the impact that low-level design decisions can have on high-level system objectives and the need for a systems-thinking approach in manufacturing system design. Results are presented to show the estimated performance improvements resulting from the new system design.

Carbon dioxide (CO2)-based refrigeration systems have been proposed as environmentally benign alternatives to current automotive air conditioners. The CO2 vapor-compression system requires very high operating pressures and complicated control strategies. Recent experimental results indicate that operating pressures comparable to those of current automotive air conditioners can be attained by the inclusion of a secondary carrier fluid (a “co-fluid”), with solution and desolution of the CO2 from the co-fluid substituting for condensation and vaporization of pure CO2. In this work, modeling tools have been developed to optimize the CO2/co-fluid cycle, including the selection of a co-fluid, the CO2/co-fluid ratio (the “loading”), and the operating conditions.

Environmental concerns have spawned renewed interest in naturally occurring refrigerants such as carbon dioxide. CO2 has attractive features such as high enthalpy of evaporation and low cost compared to halocarbons. However, the vapor pressure of CO2 is high at temperatures normally encountered in refrigeration and air conditioning systems when compared to traditional and alternative refrigerants such as CFC-12 and HFC-134a. Major research efforts are underway to investigate the transcritical CO2 cycle, in which a gas cooler instead of a condenser accomplishes heat rejection to ambient, since carbon dioxide under these conditions is above the critical point. The vapor pressure in the gas cooler may exceed 120 bar (1,740 lb/in2). In this paper a reduced pressure carbon dioxide system is reported (Ref 1). Two companion papers will address properties of working fluids (Ref 2) and thermodynamic and cycle models (Ref 3) for the low pressure carbon dioxide cycle.

Fuel Vapor Storage Systems (FVSS) on automobiles are susceptible to particle contamination. This is especially true for FVSS components mounted under the automobiles (undercarriage, chassis frame, etc.) and required to meet stringent EPA standards. Particle contamination significantly increases system restriction and reduces the effectiveness of FVSS. This paper describes a dust separator/filter developed to protect the FVSS. Accelerated field durability evaluations and measurement techniques were developed to identify clean locations, ingested contamination levels and ingested contaminant size distributions. Based on field evaluations, test methods were developed in the lab to evaluate effectiveness of several devices to control and reduce contamination. The dust separator design developed was a combination of baffle separators in series with an open cell foam filter. The dust separator was designed to meet and exceed several vehicle system design requirements.

This paper provides a technical overview of the components contained in an automotive DVD system. Discussions are limited to present in-vehicle applications of DVD-Video, DVD-ROM and DVD-Audio. Future papers will present the environmental operating requirements.

The scratch resistance of automotive plastic coatings has been studied extensively over the past few years. Most testing methodology to correlate damage of the coating to field conditions has been in the form of small particulate wearing, e.g., alumina oxide abrasive, or indentation resistance of the coating to an external probe, e.g., a nanoindentation device. The subsequent damage imparted to the coating has generally been analyzed by the amount of coating mass lost in the wear event or through a ratio of optical reflectance of the damaged area to the undamaged surface. In this paper, we attempt to delineate surface damage resistance of several automotive clearcoats through an optical interferometry methodology developed to measure volume and depth of damage incurred with small particle alumina oxide erodents in a simulated wear environment.