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Polymer Electrolyte Membrane Fuel Cell (PEMFC) is regarded as a potential alternative clean energy source for automobile applications. Key challenges to the acceptance of PEMFC for automobiles are the cost reduction, improvement in power density for its compactness, and cold-start capability. High current density operation is a promising solution for them. However, high current density operation under normal and sub-zero temperature requires more oxygen flux for the electrochemical reaction in the catalyst layer, and it causes more heat and water flux, resulting in the significant voltage losses. So, the theoretical investigation is very helpful for the fundamental understanding of complex transport phenomena in high current density operation under normal and sub-zero temperature. In this study, the numerical model was established to elucidate the impacts of mass transport phenomena on the cell performance through the numerical validation with experimental and visualization results.

The Pennsylvania State University Advanced Vehicle Team (PSU AVT) is one of the fifteen (15) participating teams at the EcoCAR 2 “Plugging In to the Future” challenge. The team has worked in the design, development and validation of converting a 2013 Chevrolet Malibu, into an advanced technology hybrid vehicle. The PSU AVT has determined that a Plug-In Series Electric Hybrid architecture best meets the design goals of the EcoCAR 2 competition. The vehicle will utilize a front-wheel drivetrain powered by a Magna E-drive; an Auxiliary Power Unit (APU) based on a naturally aspirated Weber MPE 750 engine, converted for use with E85, coupled to a UQM PowerPhase 75 generator; an Energy Storage System (ESS) based on six A123, 15s3p battery modules; and a Mototron ECM-5554-112-0904 controller as the Master Vehicle Controller (MVC).

Considerable improvements can be obtained in battery performance for hybrid electric vehicles (HEVs) by employing an electrochemistry-transport model based on a multi-physics modeling framework and ultrafast numerical algorithms. One important advantage of this approach over the lumped equivalent circuit (or look-up table) approach is the ability of the former to adapt to changes in design and control. In this work, we present mathematical and numerical details of our approach, and demonstrate the robustness of this battery model in simulation of short-pulse charge/discharge characteristic of HEV driving cycles under room and low temperatures.

Thermodynamics is the key component of materials science and engineering. The manifestation of thermodynamics is typically represented by phase diagrams, traditionally for binary and occasionally ternary systems. Consequently, the applications of thermodynamics have been rather limited in multi-component engineering materials. Computational thermodynamics, developed in the last few decades, has released the power of thermodynamics. In this presentation, fundamental thermodynamics is reviewed, followed by an introduction of computational thermodynamics in terms of first-principles calculations and thermodynamic modeling, and its application to Mg alloys.

Two of the goals of the Penn State FutureTruck project were to reduce the emissions of the hybrid electric Ford Explorer to ULEV or lower, and improve the fuel economy by 25% over the stock vehicle. The hybrid electric vehicle system is powered with a 103kW 2.5L Detroit Diesel engine which operates with a fuel blend consisting of ultra-low-sulfur diesel and biodiesel (35%). Lower emissions are inherently achieved by the use of biodiesel. Additionally, the engine was fitted with a series of aftertreatment devices in an effort to achieve the low emissions standards. Vehicle testing has shown a gasoline-equivalent fuel economy improvement of approximately 22%, a reduction in greenhouse gas emissions by approximately 38%, and meeting or exceeding stock emissions numbers in all other categories through the use of an advanced catalyst and control strategy.

Two widely available engine and hybrid electric vehicle (HEV) simulation packages have been integrated to reduce fuel consumption and pollutant emissions for a hybrid electric sport utility vehicle. WAVE, a one-dimensional engine analysis tool available from Ricardo Software, was used to model a 2.5L 103 kW Detroit Diesel engine. This model was validated against engine performance and emissions data obtained from testing in a combustion laboratory. ADVISOR, an HEV simulation software developed by the National Renewable Energy Laboratory in partnership with the Department of Energy (DOE), was used to model a 2002 Ford Explorer that is being converted into an HEV by the Penn State University FutureTruck team. By integrating the output file from WAVE as the input engine data file for ADVISOR, one can predict the effect of changes in engine parameters on vehicle emissions, fuel consumption, and power requirements for specified drive cycles.

A storage/retrieval scheme - in situ adaptive tabulation (ISAT) [1] - is used to implement detailed chemistry in a multidimensional engine CFD code. The emphasis is on predicting autoignition in nearly homogeneous and moderately non-homogeneous mixtures (HCCI); preliminary results for highly non-homogeneous direct-injection autoignition also are reported. Speedups approaching a factor of 100 have been realized with ISAT compared to direct integration of the chemical source terms; factors of five-to-ten are more readily obtainable. In the standard ISAT method, table size increases as the square of the number of chemical species in the reaction mechanism; here linear scaling is achieved by limiting the set of independent tabulation variables, while still retaining the full chemical mechanism. A key to effective use of storage/retrieval is judicious specification of the control parameters; guidelines for parameter specification are presented.

Environmentally friendly fuels and lubricants research on hydraulic fluids, engine oils, greases and industrial applications is of interest to government agencies and manufacturers of equipment, engines and vehicles. The key to increasing the use of renewable natural resources is developing fluids of equivalent performance to petroleum base products, at an acceptable product cost. The well known drawbacks of vegetable oils are oxidation stability and low temperature properties. This study compares commercial fluids and laboratory formulations as to their rheological properties and uses different approaches to solve both the low temperature and the oxidative stability problems. Frictions and wear characteristics of the fluids are evaluated and several fluids are compared laboratory bench tests.

Powder injection molding (PIM) combines the processability of plastics and the superior material properties of metals and ceramics to form high performance components. The process comprises of several stages. Metal or ceramic powder and organic materials are combined into a homogeneous feedstock which is then injection molded into a desired shape. The organic constituent is then removed from the object and sintering is done to form a rigid structure of controllable density. The important benefits afforded by PIM include near net-shape production of complex geometries in the context of low cost and rapid fabrication at high production volumes.

Thermal barrier coated diesel engines, also known as low heat rejection (LHR) engines, have offered the promise of reducing heat rejection to the engine coolant and thereby increasing overall thermal efficiency. However, the larger market potential for thermal barrier coated engines may be in retrofitting in-service diesel engines to reduce particulate emissions. Prior work by the authors has demonstrated a significant decrease in particulate emissions from a thermal barrier coated, single-cylinder, indirect injection (IDI) diesel engine, primarily through reduction of the volatile (VOF) and soluble (SOF) fraction of the particulate. This prior work relied on conventional, commercially available, petroleum-based lubricants. The present study concerns the additional benefits for particulate reduction provided by vegetable oil lubricants. These lubricants are derived from renewable resource materials and can provide a reduction in lubricant generated particulate matter.

This study shows conclusively that some of the direct microbial mutagenic activity of the soluble-organie-fraction from Diesel particulate matter can be attributed to 1-nitropyrene. 1-nitropyrene has been shown to be formed by the nitration of pyrene, and pyrene is one inherent product of the diffusion-controlled-combustion of hycrocarbons that occurs with Diesel engine operation. Nitrogen dioxide, in the presence of water vapor, is shown to be a potential nitrating agent, and this gas can be produced by the high temperature oxidation of the nitrogen contained in the oxidant. These results are based on studies which used a well-documented engine, model fuel, model oxidants, and synthetic lubricant.

The 2-stroke cycle engine has not been subject to extensive exhaust emission research because small vehicles which commonly employ 2-stroke cycle engines are not covered by federal emission regulations. This paper reports the results of a 2-stroke engine study conducted to determine the level of the unburned hydrocarbon (HC) emission and its source. Other gas phase exhaust emissions are reported as well. Exhaust composition curves were generated from a material balance model with HCs included as a product. The calculated curves were used in the analysis of the experimental data. It was determined that 25-40% of the fuel air mixture was short-circuited to the exhaust in the scavenging process which resulted in unburned HC concentrations of 5000-1000 ppm hexane equivalent. It was found that short-circuiting is a function of load but is relatively independent of speed.

The paper presents a composite picture of current knowledge concerning characteristics and causes of friction between tire and road. The mechanisms that control development of friction forces in the contact area of a tire in rolling, driving, braking, and cornering, are related to sliding of a simple rubber block. In both cases, friction is due to a combination of adhesion and hysteresis. On dry, smooth surfaces adhesion predominates while hysteresis is principal factor on wavy, lubricated surfaces. Influence of normal pressure, sliding velocity, temperature, deformation frequency, and contamination on both friction components are dealt with. Conditions in contact area are analyzed and maximum coefficients obtainable in the several modes of operation are derived. Measures to improve frictional coupling between tire and pavement are outlined.