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Particle swarm optimization (PSO) is a relatively new stochastic optimization algorithm and has gained much attention in recent years because of its fast convergence speed and strong optimization ability. However, PSO suffers from premature convergence problem for quick losing of diversity. That is to say, if no particle discovers a new superiority position than its previous best location, PSO algorithm will fall into stagnation and output local optimum result. In order to improve the diversity of basic PSO, design of experiment technique is used to initialize the particle swarm in consideration of its space-filling property which guarantees covering the design space comprehensively. And the optimization procedure of PSO is divided into two stages, optimization stage and improving stage. In the optimization stage, the basic PSO initialized by Optimal Latin hypercube technique is conducted.

Analytical models (math or computer simulation models) are typically built on the basis of many assumptions and simplifications and hence model prediction could be inaccurate in intended applications. Model validation is thus critical to quantify and improve the degree of accuracy of these models. So far, little work considers model validation for various design configurations so that model prediction is accurate in the intended design space. Furthermore, there is a lack of effective approaches that can be used to quantify model accuracy considering different number of experimental data. To overcome these limitations, objective of this paper is to develop a model validation approach for various design configurations with a reference metric for model accuracy check considering different number of experimental data.

Internal combustion engines are operated under conditions of high exhaust gas recirculation (EGR) to reduce NOx emissions and promote enhanced combustion modes such as HCCI. However, high EGR under certain conditions also promotes nonlinear feedback between cycles, leading to the development of combustion instabilities and cyclic variability. We employ a two-zone phenomenological combustion model to simulate the onset of combustion instabilities under highly dilute conditions and to illustrate the impact of these instabilities on emissions and fuel efficiency. The two-zone in-cylinder combustion model is coupled to a WAVE engine-simulation code through a Simulink interface, allowing rapid simulation of several hundred successive engine cycles with many external engine parametric effects included.

One scenario for reducing engine out NOx in a spark ignition engine is to introduce small amounts of supplemental hydrogen to the combustion process. The supplemental hydrogen enables a gasoline engine to run lean where NOx emissions are significantly reduced and engine efficiency is increased relative to stoichiometric operation. This paper reports on a mass and energy balance model that has been developed to evaluate the overall system efficiencies of a thermal reformer-heat exchanger system capable of delivering hydrogen to the air intake of a gasoline engine. The mass and energy balance model is utilized to evaluate the conditions where energy losses associated with fuel reformation may be offset by increases in engine efficiencies.

One of the major challenges in multiobjective, multidisciplinary design optimization (MDO) is the long computational time required in evaluating the new designs' performances. To shorten the cycle time of product design, a data mining-based strategy is developed to improve the efficiency of heuristic optimization algorithms. Based on the historical information of the optimization process, clustering and classification techniques are employed to identify and eliminate the low quality and repetitive designs before operating the time-consuming design evaluations. The proposed method improves design performances within the same computation budget. Two case studies, one mathematical benchmark problem and one vehicle side impact design problem, are conducted as demonstration.

While gasoline surrogate development has progressed in the areas of more complex surrogate mixtures and in kinetic modeling tools and mechanism development, it is generally recognized that further development is still needed. This paper represents a small step in supporting this development by providing comparisons between experimental engine data and surrogate-based kinetic models. In our case, the HCCI engine data comes from a port-injected, single-cylinder research engine with intake-air heating for combustion phasing control. Timing sweeps were run at constant fuel rate for three market gasolines and five surrogate mixtures. Modeling was done using the CHEMKIN software with a gasoline mechanism set containing 1440 species and 6572 reactions. Five pure compounds were selected for the surrogate blends and include iso-octane, n-heptane, toluene, methylcyclohexane, and 1-hexene.

The Magnesium Front End Research and Development (MFERD) project under the sponsorship of Canada, China, and USA aims to develop key technologies and a knowledge base for increased use of magnesium in automobiles. The primary goal of this life cycle assessment (LCA) study is to compare the energy and potential environmental impacts of advanced magnesium based front end parts of a North American-built 2007 GM-Cadillac CTS using the current steel structure as a baseline. An aluminium front end is also considered as an alternate light structure scenario. A “cradle-to-grave” LCA is conducted by including primary material production, semi-fabrication production, autoparts manufacturing and assembly, transportation, use phase, and end-of-life processing of autoparts. This LCA study was done in compliance with international standards ISO 14040:2006 [1] and ISO 14044:2006 [2].

The affordability of today's and future advanced technology vehicles (i.e., diesel, hybrid, and fuel cell) developed for improved fuel economy remains a concern with respect to final consumer acceptance. The automotive system cost model (ASCM) developed for the production cost estimates at a level of five major subsystems and 35+ components, has been used here to address the affordability issue of advanced technology vehicles. Scenarios encompassing five alternative powertrain and three body options for a mid-size vehicle under two different timeframes (i.e., 2002 and 2010) were considered to determine the cost-effectiveness of among the competing technology options within the same timeframe and between the two timeframes.