Download or read book Drag Optimization of Light Trucks Using Computational Fluid Dynamics written by Nathan A. Williams and published by . This book was released on 2003-09-01 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are 80 million light trucks on the road today with suboptimal aerodynamic forms. Previous research has found that several miles per gallon can be saved by specifically tailoring truck bodies for reduced aerodynamic drag. Even greater savings can be obtained if the shape of the trucks is numerically optimized. This could reduce fuel consumption in the United States by billions of gallons per year. The purpose of this research is to develop and quantify optimal light truck canopy designs using computational fluid dynamics (CFD). Both two-dimensional and three-dimensional models are used to do this. Initially, this research focuses on quantifying and generalizing the effects of traditional automotive aerodynamic accessories, such as canopies and air dams. Once the effects of various form factors are quantified an optimization of the canopy is performed. This thesis demonstrates a method for drag reduction using CFD and traditional numerical optimization techniques. Lastly, the optimized forms are physically constructed and their effects on fuel economy are compared to the CFD prediction. The results indicate that the CFD formulation provides an accurate predictor for improving fuel economy and drag characteristics. The prototype air dam and optimally shaped canopy generated a 21.23% savings in terms of fuel economy.
Download or read book Experiments and Computer Simulations on Aerodynamic Drag Reduction of Light Vehicle trailer Systems written by Henry R. Boyer and published by . This book was released on 2015 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind-tunnel experiments and Computational Fluid Dynamics (CFD) were performed to study the effect a deflector had on the flow and drag force associated with a 2010 F-150 truck and cargo trailer (Light Vehicle-Trailer System - LVTS). Image Correlation Velocimetry (ICV) on smokewire streaklines measured the velocity field on the model mid-plane. CFD was used to elucidate the flow, calculate the drag force, and study the effects of a moving ground-plane and blockage. The drag was reduced by approximately 13% at a Re of 14,900 with a moving ground-plane, and 17% without. Experiments suggested that the large difference in Re between wind-tunnel and the full-scale 5 million is not expected to significantly diminish the full-scale relevance of the drag results. One low Re effect was the presence of a separation bubble on the hood of the tow vehicle whose size reduced with an increase in Re. Three other characteristic flow patterns were identified: separation off the lead vehicle cab, stagnation of the free-stream on the trailer face for the no-deflector case, and subsequent separation at the trailer front corner. Comparisons of the ICV and CFD results with no deflector indicated good agreement, particularly in the direction of the velocity vectors. The ICV method under-evaluated the speed of the flow by up to 15%. The smoke streaklines and CFD streamlines agreed well for the no deflector case. However, for the deflector case, the CFD found an entirely different topological solution absent in the experiment. A pair of vertically-oriented vortices were found, wrapped around the front of the trailer on the mid-plane.
Download or read book Computational Investigation of Drag Reduction of Trucks written by Yangyang Hu and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Fluid Dynamic (CFD) simulations of the steady state Reynolds-Averaged Navier-Stokes equations using the second order k- turbulence model were performed to investigate the Drag Coefficients of the Class 8 trucks under different geometric configurations. The reduction rates of aerodynamic drag using several add-on devices such as base flap, boat tail, underbody skirt and tractor-trailer gap are investigated through the CFD simulations. Moreover, simulations by using different lengths and angles of the base flap and boat tail were conducted; the comparison indicates that the base flap design is more effective for the drag reduction. The optimized range of the length and angle of the base flap design is confirmed by a set of systematic CFD simulations. Also, a set of wind tunnel experiments had been conducted to confirm the outcomes from the CFD simulations."
Download or read book The Aerodynamics of Heavy Vehicles Trucks Buses and Trains written by Rose McCallen and published by Springer Science & Business Media. This book was released on 2004-09 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book includes the carefully edited contributions to the United Engineering Foundation Conference: The Aerodynamics of Heavy Vehicles: Trucks, Buses and Trains held in Monterey, California from December 2-6, 2002. This conference brought together 90 leading engineering researchers discussing the aerodynamic drag of heavy vehicles. The book topics include a comparison of computational fluid dynamics calculations using both steady and unsteady Reynolds-averaged Navier-Stokes, large-eddy simulation, and hybrid turbulence models and experimental data obtained from wind tunnel experiments. Advanced experimental techniques including three-dimensional particle image velocimetry are presented as well, along with their use in evaluating drag reduction devices.
Download or read book The Aerodynamics of Heavy Vehicles Trucks Buses and Trains written by Rose McCallen and published by Springer. This book was released on 2013-11-20 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is our pleasure to present these proceedings from the United Engineering Foundation Conference on The Aerodynamics of Heavy Vehicles: Trucks, Buses and Trains held December 2-6, 2002, in Monterey, California. This Department of Energy, United Engineering Foundation, and industry sponsored conference brought together 90 leading engineering researchers from around the world to discuss the aerodynamic drag of heavy vehicles. Participants from national labs, academia, and industry, including truck manufacturers, discussed how computer simulation and experimental techniques could be used to design more fuel efficient trucks, buses, and trains. Conference topics included comparison of computational fluid dynamics calculations using both steady and unsteady Reynolds-averaged Navier-Stokes, large-eddy simulation, and hybrid turbulence models and experimental data obtained from the Department of Energy sponsored and other wind tunnel experiments. Advanced experimental techniques including three-dimensional particle image velocimetry were presented, along with their use in evaluating drag reduction devices. We would like to thank the UEF conference organizers for their dedication and quick response to sudden deadlines. In addition, we would like to thank all session chairs, the scientific advisory committee, authors, and reviewers for their many hours of dedicated effort that contributed to a successful conference and resulted in this document of the conference proceedings. We also gratefully acknowledge the support received from the United Engineering Foundation, the US Department of Energy, Lawrence Livermore National Laboratory, Volvo Trucks America, International Truck and Engine Corporation, and Freightliner LLC.
Download or read book Turbulent Drag Reduction by Surfactant Additives written by Feng-Chen Li and published by John Wiley & Sons. This book was released on 2012-01-10 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent drag reduction by additives has long been a hot research topic. This phenomenon is inherently associated with multifold expertise. Solutions of drag-reducing additives are usually viscoelastic fluids having complicated rheological properties. Exploring the characteristics of drag-reduced turbulent flows calls for uniquely designed experimental and numerical simulation techniques and elaborate theoretical considerations. Pertinently understanding the turbulent drag reduction mechanism necessities mastering the fundamentals of turbulence and establishing a proper relationship between turbulence and the rheological properties induced by additives. Promoting the applications of the drag reduction phenomenon requires the knowledge from different fields such as chemical engineering, mechanical engineering, municipal engineering, and so on. This book gives a thorough elucidation of the turbulence characteristics and rheological behaviors, theories, special techniques and application issues for drag-reducing flows by surfactant additives based on the state-of-the-art of scientific research results through the latest experimental studies, numerical simulations and theoretical analyses. Covers turbulent drag reduction, heat transfer reduction, complex rheology and the real-world applications of drag reduction Introduces advanced testing techniques, such as PIV, LDA, and their applications in current experiments, illustrated with multiple diagrams and equations Real-world examples of the topic’s increasingly important industrial applications enable readers to implement cost- and energy-saving measures Explains the tools before presenting the research results, to give readers coverage of the subject from both theoretical and experimental viewpoints Consolidates interdisciplinary information on turbulent drag reduction by additives Turbulent Drag Reduction by Surfactant Additives is geared for researchers, graduate students, and engineers in the fields of Fluid Mechanics, Mechanical Engineering, Turbulence, Chemical Engineering, Municipal Engineering. Researchers and practitioners involved in the fields of Flow Control, Chemistry, Computational Fluid Dynamics, Experimental Fluid Dynamics, and Rheology will also find this book to be a much-needed reference on the topic.
Download or read book Design of Tractor trailer Add on Drag Reduction Devices Using CFD written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Drag reduction is one way to reduce vehicle fuel consumption. Tractor-trailers have a higher drag coefficient than other vehicles due to their bluff-body shape. Over the years, numerous add-on devices have been invented to help reducing drag and fuel consumption. The current research goal is to design new add-on devices to further reduce drag of a tractor-trailer. A 3D simplified (Ahmed) model was built as the baseline model. Computational fluid dynamics (CFD) in the form of unsteady Reynolds-averaged Navier-Stokes (RANS) and DES simulations were used to determine viable design strategies. The predicted drag coefficient of the baseline model showed good agreement with experimental data. Grid sensitivity of baseline model was also studied prior to new designs. A hump and a modified curved base flap were created as the new designs which were both optimized for best drag reduction effect. The results from the optimized design were shown to have 50.9% drag reduction compared to the baseline model. This demonstrates the possibility of fuel saving while applying these devices on a real truck. With the optimized design, three different turbulent models were tested to compare with each other - [kappa]-epsilon, RANS (standard and RNG), and DES models. The results showed that DES model can predict more flow unsteadiness than RANS models. However, the standard [kappa]-epsilon model still predicted the most accurate drag coefficient among the three models.
Download or read book The Aerodynamics of Heavy Vehicles III written by Andreas Dillmann and published by Springer. This book was released on 2015-08-29 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains papers presented at the International conference “The Aerodynamics of Heavy Vehicles III: Trucks, Buses and Trains” held in Potsdam, Germany, September 12-17, 2010 by Engineering Conferences International (ECI). Leading scientists and engineers from industry, universities and research laboratories, including truck and high-speed train manufacturers and operators were brought together to discuss computer simulation and experimental techniques to be applied for the design of more efficient trucks, buses and high-speed trains in the future. This conference was the third in the series after Monterey-Pacific Groove in 2002 and Lake Tahoe in 2007.The presentations address different aspects of train aerodynamics (cross wind effects, underbody flow, tunnel aerodynamics and aeroacoustics, experimental techniques), truck aerodynamics (drag reduction, flow control, experimental and computational techniques) as well as computational fluid dynamics and bluff body, wake and jet flows.
Download or read book Analysis of Novel Techniques of Drag Reduction and Stability Increase for Sport Utility Vehicles Using Computational Fluid Dynamics written by Ahmed Ali Shakir Al-Saadi and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Parallel Computational Fluid Dynamics 2006 written by Jang-Hyuk Kwon and published by Elsevier. This book was released on 2007-09-12 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings from Parallel CFD 2006 covers all aspects of parallel computings and its applications. Although CFD is one of basic tools for design procedures to produce machineries, such as automobiles, ships, aircrafts, etc., large scale parallel computing has been realized very recently, especially for the manufactures. Various applications in many areas could be experienced including acoustics, weather prediction and ocean modeling, flow control, turbine flow, fluid-structure interaction, optimization, heat transfer, hydrodynamics.- Report on current research in the field in an area which is rapidly changing - Subject is important to all interested in solving large fluid dynamics problems - Interdisciplinary activity. Contributions include scientists with a variety of backgrounds
Download or read book Progress in Reducing Aerodynamic Drag for Higher Efficiency of Heavy Duty Trucks class 7 8 written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Mandat der Landvogtei Rheintal ber Massnahmen gegen Viehseuchen 1753 written by and published by . This book was released on 1753 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book FY 2004 Annual Report written by C. J. Roy and published by . This book was released on 2004 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this report is: (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 potential of new drag-reduction devices. The approaches used were: (1) Develop and demonstrate the ability to simulate and analyze aerodynamic flow around heavy truck vehicles using existing and advanced computational fluid dynamics (CFD) tools; (2) Through an extensive experimental effort, generate an experimental data base for code validation; (3) Using experimental data base, validate computations; (4) Provide industry with design guidance and insight into flow phenomena from experiments and computations; and (5) Investigate aero devices (e.g., base flaps, tractor-trailer gap stabilizer, underbody skirts and wedges, blowing and acoustic devices), provide industry with conceptual designs of drag reducing devices, and demonstrate the full-scale fuel economy potential of these devices.
Download or read book Aerodynamics of Road Vehicles written by Wolf-Heinrich Hucho and published by Elsevier. This book was released on 2013-10-22 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamics of Road Vehicles details the aerodynamics of passenger cars, commercial vehicles, sports cars, and race cars; their external flow field; as well as their internal flow field. The book, after giving an introduction to automobile aerodynamics and some fundamentals of fluid mechanics, covers topics such as the performance and aerodynamics of different kinds of vehicles, as well as test techniques for their aerodynamics. The book also covers other concepts related to automobiles such as cooling systems and ventilations for vehicles. The text is recommended for mechanical engineers and phycisists in the automobile industry who would like to understand more about aerodynamics of motor vehicles and its importance on the field of road safety and automobile production.
Download or read book Annual Index abstracts of SAE Technical Papers 2004 written by and published by . This book was released on 2005 with total page 962 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Fluid Dynamics Drag Prediction Results from the Viscous Transonic Airfoil Workshop written by and published by . This book was released on 1988 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
