Rose McCallen

The aerodynamics of heavy vehicles : trucks, buses, and trains

Aerodynamics and Other Efficiencies in Transporting Goods.- Commercial Vehicle Aerodynamic Drag Reduction: Historical Perspective as a Guide.- The Status of Detached-Eddy Simulation for Bluff Bodies.- Exploring the Flow Around a Simplified Bus with Large Eddy Simulation and Topological Tools.- Unsteady Flow Around Cylinders with Cavities.- Complex CFD for Everyday Use - Practical Applications for Vehicle Analysis.- Large Eddy Simulation of Flow Around the Ahmed Body.- Detached-Eddy Simulation of the Ground Transportation System.- Time Dependent vs. Steady State Calculations of External Aerodynamics.- Aerodynamics of Ground Vehicles - Toward Reliable and Affordable CFD.- Improved Tractor-Trailer Integration and Aerodynamics Through the Use of CFD.- Large Eddy Simulation of Turbulence Via Lattice Boltzmann Based Approach: Fundamental Physics and Practical Applications.- Aspects of CFD Application to Vehicle Aerodynamic Design.- PIV Study of the Near Wake of a Pickup Truck.- Applications of DDPIV to Studies Associated with Road Vehicles.- Molecular Tagging Velocimetry (MTV) and Its Automotive Applications.- Quantitative Flow Visualization for Large Scale Wind Tunnels.- An Experimental Study of the Generic Conventional Model (GCM) in the NASA Ames 7-by-10-Foot Wind Tunnel.- The Measurement of Wake and Gap Flows of the Generic Conventional Truck Model (GCM) Using Three-Component PIV.- On the Aerodynamics of Tractor-Trailers.- RANS Simulations of a Simplified Tractor/Trailer Geometry.- Computational Simulation of a Heavy Vehicle Trailer Wake.- Drag Reduction of Two-Dimensional Bodies by Addition of Boat Tails.- Drag Reduction of a Tractor-Trailer Using Planar Boat Tail Plates.- RANS Simulations of Passive and Active Drag Reduction Devices for a Road Vehicle.- Pneumatic Heavy Vehicle Aerodynamic Drag Reduction, Safety Enhancement, and Performance Improvement.- Base Flaps and Oscillatory Perturbations to Decrease Base Drag.- Use of Computational Aerodynamics for Commercial Vehicle Development at DaimlerChrysler.- Numerical Simulation of the Flow About a Train Model.- Adaptation of Eddy-Viscosity Turbulence Models to Unsteady Separated Flow Behind Vehicles.- Simulation of Vehicle Aerodynamics Using a Vortex Element Method.- Energetic and CFD Modeling Considerations of Thermal Management.- Measurement of Underhood Temperatures with Various Ventilations.- Measurement and Analysis of Underhood Ventilation Air Flow and Temperatures for an Off-Road Machine.- Flow Field and Thermal Management Analysis of an Armored Vehicle Engine Compartment.- Experiments and CFD in Train Aerodynamics: A Young and Turbulent Association Full of Potential.- Recent Studies of Train Slipstreams.- Aerodynamic Effects in Railway Tunnels as Speed is Increased.- Flow-Induced Vibration of High-Speed Trains in Tunnels.- How to Reduce the Cross Wind Sensitivity of Trains.- CFD Study of Side Wind Effects on a High Speed Train.- Commercial CFD Code Validation for Heavy-Vehicle External Aerodynamics Simulation.- Computational Parametric Study on External Aerodynamics of Heavy Trucks.- Applicability of the Vortex Methods for Aerodynamics of Heavy Vehicles.- Development of a Wind Tunnel Model Mounting Configuration for Heavy Duty Trucks..- A Ground-Based Research Vehicle for Base Drag Studies at Subsonic Speeds.- Splash and Spray Measurement and Control: Recent Progress in Quebec.- Wind-Tunnel Evaluation of an Aerodynamic Heat Exchanger.- Automated Driving of Trucks and Buses: Opportunities for Increasing Productivity and Safety While Reducing Fuel Use and Emissions.- Author Index.

Progress in Reducing Aerodynamic Drag for Higher Efficiency of Heavy Duty Trucks (Class 7-8)

This paper describes research and development for reducing the aerodynamic drag of heavy vehicles by demonstrating new approaches for the numerical simulation and analysis of aerodynamic flow. In addition, greater use of newly developed computational tools holds promise for reducing the number of prototype tests, for cutting manufacturing costs, and for reducing overall time to market. Experimental verification and validation of new computational fluid dynamics methods are also an important part of this approach. Experiments on a model of an integrated tractor-trailer are underway at NASA Ames Research Center and the University of Southern California. Companion computer simulations are being performed by Sandia National Laboratories, Lawrence Livermore National Laboratory, and California Institute of Technology using state-of-the-art techniques, with the intention of implementing more complex methods in the future.

DOE's Effort to Reduce Truck Aerodynamic Drag Through Joint Experiments and Computations

Class 8 tractor-trailers are responsible for 11-12% of the total US consumption of petroleum. Overcoming aero drag represents 65% of energy expenditure at highway speeds. Most of the drag results from pressure differences and reducing highway speeds is very effective. The goal is to reduce aerodynamic drag by 25% which would translate to 12% improved fuel economy or 4,200 million gal/year. Objectives are: (1) In support of DOEs mission, provide guidance to industry in the reduction of aerodynamic drag; (2) To shorten and improve design process, establish a database of experimental, computational, and conceptual design information; (3) Demonstrate new drag-reduction techniques; and (4) Get devices on the road. Some accomplishments are: (1) Concepts developed/tested that exceeded 25% drag reduction goal; (2) Insight and guidelines for drag reduction provided to industry through computations and experiments; (3) Joined with industry in getting devices on the road and providing design concepts through virtual modeling and testing; and (4) International recognition achieved through open documentation and database.

Aerodynamic Drag of Heavy Vehicles (Class 7-8): Simulation and Benchmarking

This paper describes research and development for reducing the aerodynamic drag of heavy vehicles by demonstrating new approaches for the numerical simulation and analysis of aerodynamic flow. Experimental validation of new computational fluid dynamics methods are also an important part of this approach. Experiments on a model of an integrated tractor-trailer are underway at NASA Ames Research Center and the University of Southern California (USC). Companion computer simulations are being performed by Sandia National Laboratories (SNL), Lawrence Livermore National Laboratory (LLNL), and California Institute of Technology (Caltech) using state-of-the-art techniques.

Computational Simulation of a Heavy Vehicle Trailer Wake

To better understand the flow mechanisms that contribute to the aerodynamic drag of heavy vehicles, unsteady largeeddy simulations are performed to model the wake of a truncated trailer geometry above a no-slip surface. The truncation of the heavy vehicle trailer is done to reduce the computational time needed to perform the simulations. Both unsteady and time-averaged results are presented from these simulations for two grids. A comparison of velocity fields with those obtained from a wind tunnel study demonstrate that there is a distinct difference in the separated wake of the experimental and computational results, perhaps indicating the influence of the geometry simplification, turbulence model, boundary conditions, or other aspects of the chosen numerical approach.

Science at LLNL with IBM Blue Gene/Q

Lawrence Livermore National Laboratory (LLNL) has a long history of working with IBM on Blue Gene® supercomputers. Beginning in November 2001 with the joint announcement of a partnership to expand the Blue Gene research project (including Blue Gene®/L and Blue Gene®/P), the collaboration extends to this day with LLNL planning for the installation of a 96-rack Blue Gene®/Q (called Sequoia) supercomputer. As with previous machines, we envision Blue Gene/Q will be used for a wide array of applications at LLNL, ranging from meeting programmatic requirements for certification to increasing our understanding of basic physical processes. We briefly describe a representative sample of mature codes that span this application space and scale well on Blue Gene hardware. Finally, we describe advances in multi-scale whole-organ modeling of the human heart as an example of breakthrough science that will be enabled with the Blue Gene/Q architecture.

DOE Project on Heavy Vehicle Aerodynamic Drag FY 2005 Annual Report

Class 8 tractor-trailers consume 11-12% of the total US petroleum use. At high way speeds, 65% of the energy expenditure for a Class 8 truck is in overcoming aerodynamic drag. The project objective is to improve fuel economy of Class 8 tractor-trailers by providing guidance on methods of reducing drag by at least 25%. A 25% reduction in drag would present a 12% improvement in fuel economy at highway speeds, equivalent to about 130 midsize tanker ships per year. Specific goals include: (1) Provide guidance to industry in the reduction of aerodynamic drag of heavy truck vehicles; and (2) Establish a database of experimental, computational, and conceptual design information, and demonstrate the potential of new drag-reduction devices.

Aerodynamic Design of Heavy Vehicles Reporting Period September 2001 through January 15, 2002

Activities for this first quarter include continued effort in simulating the experiments performed in the NASA 7-ft x 10-ft wind tunnel with the GTS geometry using both LLNLs advanced computational tools and NASAs Overflow code. Along with this analysis effort, we continue to implement advanced algorithms in LLNLs models to improve simulation speed and accuracy and to verify and validate these advanced simulation tools.