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Fuel cell vehicles are currently undergoing extensive research and development because of their potential for high efficiency and low emissions. A complete well-to-wheels evaluation is helpful when considering the introduction of advanced vehicles that could use a new fuel, such as hydrogen. Several modeling tools developed by Argonne National Laboratory were used to evaluate the impact of several new vehicle configurations. A transient vehicle simulation software code, PSAT (Powertrain System Analysis Toolkit), was used with a transient fuel cell model derived from GCTool (General Computational Toolkit); and GREET (Greenhouse gases, Regulated Emissions and Energy use in Transportation) was employed in estimating well-to-tank performances. This paper compares the well-to-wheels impacts of several advanced SUVs, including conventional, parallel and series hybrid-electric and fuel cell vehicles.

The National Highway Traffic Safety Administration (NHTSA) plays a crucial role in guiding the formulation of Corporate Average Fuel Economy (CAFE) standards, and at the forefront of this regulatory process stands Argonne National Laboratory (Argonne). Argonne, a U.S. Department of Energy (DOE) research institution, has developed Autonomie—an advanced and comprehensive full-vehicle simulation tool that has solidified its status as an industry standard for evaluating vehicle performance, energy consumption, and the effectiveness of various technologies. Under the purview of an Inter-Agency Agreement (IAA), the DOE Argonne Site Office (ASO) and Argonne have assumed the responsibility of conducting full-vehicle simulations to support NHTSA's CAFE rulemaking initiatives. This paper introduces an innovative approach that hinges on a large-scale simulation process, encompassing standard regulatory driving cycles tailored to various vehicle classes and spanning diverse timeframes.

Connectivity and automation provide the potential to use information about the environment and future driving to minimize energy consumption. Aerodynamic drag can also be reduced by close-gap platooning using information from vehicle-to-vehicle communications. In order to achieve these goals, the designers of control strategies need to simulate a wide range of driving situations in which vehicles interact with other vehicles and the infrastructure in a closed-loop fashion. RoadRunner is a new model-based system engineering platform based on Autonomie software, which can collectively provide the necessary tools to predict energy consumption for various driving decisions and scenarios such as car-following, free-flow, or eco-approach driving, and thereby can help in developing control algorithms.

Other than in Japan, medium and heavy duty vehicles (MHDVs) are not regulated despite accounting for a significant portion of the fuel consumed (about 26% in the US in 2008). Government agencies worldwide are currently evaluating options to address that issue. Due to the large number of vehicle applications, some of them being “one of a kind”, vehicle modelling and simulation offers an attractive solution to medium and heavy duty regulations. This paper discusses the advantages and challenges of vehicle simulation to support regulations.

Over the past couple of years, Argonne National Laboratory has tested, analyzed, and validated automobile models for the light duty vehicle class, including several types of powertrains including conventional, hybrid electric, plug-in hybrid electric and battery electric vehicles. Argonne’s previous works focused on the light duty vehicle models, but no work has been done on medium and heavy-duty vehicles. This study focuses on the validation of shifting control in advanced automatic transmission technologies for medium duty vehicles by using Argonne’s model-based high-fidelity, forward-looking, vehicle simulation tool, Autonomie. Different medium duty vehicles, from Argonne’s own fleet, including the Ram 2500, Ford F-250 and Ford F-350, were tested with the equipment for OBD (on-board diagnostics) signal data record. For the medium duty vehicles, a workflow process was used to import test data.

This paper introduces control strategy analysis and performance degradation for the 2010 Toyota Prius under different thermal conditions. The goal was to understand, in as much detail as possible, the impact of thermal conditions on component and vehicle performances by analyzing a number of test data obtained under different thermal conditions in the Advanced Powertrain Research Facility (APRF) at Argonne National Laboratory. A previous study analyzed the control behavior and performance under a normal ambient temperature; thus the first step in this study was to focus on the impact when the ambient temperature is cold or hot. Based on the analyzed results, thermal component models were developed in which the vehicle controller in the simulation was designed to mimic the control behavior when temperatures of the components are cold or hot. Further, the performance degradation of the components was applied to the mathematical models based on analysis of the test data.

Argonne National Laboratory (ANL), working with the Partnership for a New Generation of Vehicles (PNGV), maintains hybrid vehicle simulation software, the PNGV System Analysis Toolkit (PSAT). PSAT, originally proprietary, has been used by both DOE and the “Big Three” as a modeling tool. The number of PSAT users has increased recently because 15 universities participating in the 2001 FutureTruck competition were given the software for their use. PSAT allows companies to look at new types of vehicles (hybrids) and choose the best configuration according to customer expectations within a minimum of time. PSAT, a forward-looking model, allows the user to simulate a large number of different configurations (conventional, series, parallel, and power split). PSAT is well suited for development of control strategies; by using accurate dynamics component models as its code, PSAT can be implemented directly and tested at the bench scale or in a vehicle.

The Cooperative Automotive Research for Advanced Technology (CARAT) program is designed to accelerate the commercialization of innovative technologies that will overcome barriers to achieving the goals of the Partnership for a New Generation of Vehicles Program. Aimed at harnessing the creativity and capabilities of American small businesses and colleges and universities, this unique technology R&D program seeks to develop and bring advanced technologies into use in production vehicles at a faster rate. CARAT's focus is developing and commercializing technology that overcomes key technical barriers preventing the production of vehicles with ultra-high fuel efficiency. CARAT begins with technologies that already have a firm technical basis and, through a unique three-stage process, ends with fully validated technologies ready for mass production. The program is open to all U.S. entrepreneurs and small businesses, colleges, and universities.

Argonne National Laboratory (Argonne) and Idaho National Laboratory (INL), working with the FreedomCAR and Fuels Partnership, lead activities in vehicle dynamometer and fleet testing as well as in modeling activities. By using Argonne’s Advanced Powertrain Research Facility (APRF), the General Motors (GM) Tahoe 2-mode was instrumented and tested in the 4-wheel-drive test facility. Measurements included both sensors and controller area network (CAN) messages. In this paper, we describe the vehicle instrumentation as well as the test results. On the basis of the analysis performed, we discuss the vehicle model developed in Argonne’s vehicle simulation tool, the Powertrain System Analysis Toolkit (PSAT), and its comparison with test data. Finally, on-road vehicle data, performed by INL, is discussed and compared with the dynamometer results.

Many of today's advanced simulation tools are suitable for modeling specific systems; however, they provide rather limited support for model building and management. Setting up a detailed vehicle simulation model requires more than writing down state equations and running them on a computer. In this paper, we describe how modern software techniques can be used to support modeling and design activities, with the objective of providing better system models more quickly by assembling these system models in a “plug-and-play” architecture. Instead of developing detailed models specifically for Argonne National Laboratory's Autonomie modeling tool, we have chosen to place emphasis on integrating and re-using the system models, regardless of the environment in which they were initially developed. By way of example, this paper describes a vehicle model composed of a detailed engine model from GT Power, a transmission from AMESim, and with vehicle dynamics from CarSim.

A new type of approval procedure for light-duty vehicles, the Worldwide harmonized Light vehicles Test Procedure (WLTP), developed by an initiative of the United Nations Economic Commission for Europe, will come into force by the end of 2017. The current European type-approval procedure for energy consumption and CO2 emissions of cars, the New European Driving Cycle (NEDC), includes a number of tolerances and flexibilities that no longer accurately reflect state-of-the-art technologies. Indeed, on the basis of an analysis of real-world driving data from the German website spritmonitor.de, the ICCT concluded that the differences between official laboratory and real-world fuel consumption and CO2 values were around 7% in 2001. This discrepancy has been increasing continuously since then to around 30% in 2013, with notable differences found between individual manufacturers and vehicle models.

In this study, three batteries were designed and these designs were evaluated in a hybrid vehicle simulation program. The battery designs were based on laboratory tests of 18650 cells for which a Lumped Parameter Battery Model was employed to correlate the cell impedance data. The three battery designs were each tested on three driving cycles, the Federal Urban Driving Schedule, the Highway Fuel Economy Test, and a special cycle developed to test the full power of the vehicle. The results of these simulation tests showed that the battery impedances were low for much of the time because the discharging and charging currents are not maintained at high levels for long periods of time on these cycles. For these conditions, the rates of heat generation in the batteries that were calculated by the simulation programs were low and may not be a serious problem.

Cavitation plays an important role in fuel injection systems. It alters the nozzle's internal flow structure and discharge coefficient, and also contributes to injector wear. Quantitatively measuring and mapping the cavitation vapor distribution in a fuel injector is difficult, as cavitation occurs on very short time and length scales. Optical measurements of transparent model nozzles can indicate the morphology of large-scale cavitation, but are generally limited by the substantial amount of scattering that occurs between vapor and liquid phases. These limitations can be overcome with x-ray diagnostics, as x-rays refract, scatter and absorb much more weakly from phase interfaces. Here, we present an overview of some recent developments in quantitative x-ray diagnostics for cavitating flows. Measurements were conducted at the Advanced Photon Source at Argonne National Laboratory, using a submerged plastic test nozzle.

Present-day battery technologies support a battery electric vehicle with a 300mile range (BEV 300), but the cost of such a vehicle hinders its large-scale adoption by consumers. The U.S. Department of Energy (DOE) has set aggressive cost targets for battery technologies. At present, no single technology meets the cost, energy, and power requirements of a BEV 300, but a combination of multiple batteries with different capabilities might be able to lower the overall cost closer to the DOE target. This study looks at how such a combination can be implemented in vehicle simulation models and compares the vehicle manufacturing and operating costs to a baseline BEV 300. Preliminary analysis shows an opportunity to modestly reduce BEV 300 energy storage system cost by about 8% using a battery pack that combines an energy and power battery. The baseline vehicle considered in the study uses a single battery sized to meet both the power and energy requirements of a BEV 300.

This paper assesses the technical potential, costs and benefits of improving the fuel economy of light-duty trucks over the next five to ten years in the United States using conventional technologies. We offer an in-depth analysis of several technology packages based on a detailed vehicle system modeling approach. Results are provided for fuel economy, cost, oil savings and reductions in greenhouse gas emissions. We examine a range of refinements to body, powertrain and electrical systems, reflecting current best practice and emerging technologies such as lightweight materials, high-efficiency IC engines, integrated starter-generator, 42 volt electrical system and advanced transmission. In this paper, multiple technological pathways are identified to significantly improve fleet average light-duty-truck fuel economy to 27.0 MPG or higher with net savings to consumers.

While sulfur in diesel fuels helps reduce friction and prevents wear and galling in fuel pump and injector systems, it also creates environmental pollution in the form of hazardous particulates and SO2 emissions. The environmental concern is the driving force behind industry's efforts to come up with new alternative approaches to this problem. One such approach is to replace sulfur in diesel fuels with other chemicals that would maintain the antifriction and antiwear properties provided by sulfur in diesel fuels while at the same time reducing particulate emissions. A second alternative might be to surface-treat fuel injection parts (i.e., nitriding, carburizing, or coating the surfaces) to reduce or eliminate failures associated with the use of low-sulfur diesel fuels. Our research explores the potential usefulness of a near-frictionless carbon (NFC) film developed at Argonne National Laboratory in alleviating the aforementioned problems.

The addition of metal nanoparticles to standard coolant fluids dramatically increases the thermal conductivity of the liquid. The properties of the prepared nanofluids will allow for lighter, smaller, and higher efficiency spacecraft thermal control systems to be developed. Nanofluids with spherical or rod-shaped metal nanoparticles were investigated. At a volume concentration of 0.5%, the room temperature thermal conductivity of a 2 nm spherical gold nanoparticle-water solution was increased by more than 10% over water alone. Silver nanorods increased the thermal conductivity of ethylene glycol by 53% and water by 26%.

Applying nanotechnology to thermal engineering, ANL has addressed the interesting and timely topic of nanofluids. We have developed methods for producing both oxide and metal nanofluids, studied their thermal conductivity, and obtained promising results: (1) Stable suspensions of nanoparticles can be achieved. (2) Nanofluids have significantly higher thermal conductivities than their base liquids. (3) Measured thermal conductivities of nanofluids are much greater than predicted. For these reasons, nanofluids show promise for improving the design and performance of vehicle thermal management systems. However, critical barriers to further development and application of nanofluid technology are agglomeration of nanoparticles and oxidation of metallic nanoparticles. Therefore, methods to prevent particle agglomeration and degradation are required.

This study involves the battery requirements for a fuel cell-powered hybrid electric vehicle. The performances of the vehicle [a 3200-lb (1455-kg) sedan], the fuel cell, and the battery were evaluated in a vehicle simulation. Most of the attention was given to the design and performance of the battery, a lithium-ion, manganese spinel-graphite system of 75-kW power to be used with a 50-kW fuel cell. The total power performance of the system was excellent at the full operating temperatures of the fuel cell and battery. The battery cycling duty is very moderate, as regenerative braking for the Federal Urban Driving Schedule and the Highway Fuel Economy Test cycles can do all charging of the battery. Cold start-up at 20°C is straightforward, with full power available immediately.

Although many simulations and analyses of three-phase insulated gate bipolar transistor (IGBT) switching devices exist in the offline and post processing arenas, real-time simulation environments require varying levels of fidelity of real-time capable models, depending on the task at hand. This paper presents a comparison between existing basic real-time modeling techniques and more advanced techniques capable of simulating complex electrical characteristics in high fidelity, while retaining the capability of real-time simulation. Model development, simulation, and analysis of results was performed at Mississippi State University in an effort to better understand the effects of multiple brushless direct current (BLDC) IGBT inverters operating on the same high-voltage bus.