Design, Construction and Employment of a Sustainable “Urban Concept” Race Vehicle

2012 ◽  
Author(s):  
G. Galmarini ◽  
M. Gobbi ◽  
G. Mastinu
Keyword(s):  
Numerical Model ◽  
High Performance ◽  
Aerodynamic Drag ◽  
Aerodynamic Resistance ◽  
Main Body ◽  
Cfd Analysis ◽  
Motion Resistance ◽  
Vehicle Shape ◽  
Technical Regulations ◽  
Design Construction

The construction of a plug-in electrical race vehicle is presented in the paper. The vehicle is a prototype developed to be used for the Shell Eco-Marathon (SEM) competition. The main aim of SEM is to minimize fuel consumption. According to the technical regulations and the overall dimensions, the layout of the vehicle has been estimated in order to reduce the mass and the aerodynamic resistance of the vehicle. A high performance aerodynamic shape has been developed starting from the “Morelli’s shape” which has been further optimized to reduce the aerodynamic drag. A CFD analysis has been completed to refine the vehicle shape and to reach the final body geometry. To reduce the frontal area the wheels have been connected to the main body by using CFRP wing beams and both suspension system and powertrain, have been integrated into the wheels. A highly efficient powertrain has been developed and an electronic differential has been implemented. All the subsystems have been optimized both to reduce the motion resistance of the vehicle and to maximize the efficiency. A numerical model of the vehicle has been developed in order to aid the design and to simulate the race strategy on different competition tracks. The model has been validated by considering data acquired during the race.

Design of an Hydrogen Powered Electrical Race Vehicle

2011 ◽  
Author(s):  
G. Galmarini ◽  
G. Mastinu ◽  
M. Gobbi ◽  
M. Mauri
Keyword(s):  
Fuel Consumption ◽  
High Performance ◽  
Aerodynamic Drag ◽  
Fem Analysis ◽  
The Body ◽  
Cfd Analysis ◽  
Space Requirement ◽  
Aerodynamic Shape ◽  
Vehicle Shape ◽  
Technical Regulations

The construction of a hydrogen powered electrical race vehicle is presented in this paper. This prototype has been developed to be used in the Shell Eco-Marathon competition. The main aim of this event is to reduce the fuel consumption. According to the technical regulations, the minimum space requirement has been estimated on the basis of the driver anthropometric dimensions. A high performance aerodynamic shape has been developed by starting from an axis-symmetric body which has been optimized for reducing the aerodynamic drag while running close to the ground. CFD analysis has been performed to refine the vehicle shape and to reach the final body geometry. With the help of the FEM analysis, a complex CFRP layout of a monocoque chassis has been defined in order to maximize the body stiffness and to reduce the mass. All the subsystems have been optimized both to reduce the resistance of the vehicle and to maximize the powertrain efficiency. Lab tests have been performed to validate the CFD and FEM analysis. The result of this work is the design of a vehicle, optimized in shape, mass and efficiency, to take part at Shell Eco-Marathon competition.

Aerodynamic Automobile Shape Optimization by Incorporating Reverse Shape Design Method With CFD Analysis

2017 ◽  
Author(s):  
Kisun Song ◽  
Kyung Hak Choo ◽  
Jung-Hyun Kim ◽  
Dimitri N. Mavris
Keyword(s):  
Design Optimization ◽  
Aerodynamic Drag ◽  
Design Method ◽  
Shape Design ◽  
Cfd Analysis ◽  
Simple Arithmetic ◽  
Design Variables ◽  
3D Geometry ◽  
Geometric Entity ◽  
Aerodynamic Drag Reduction

In modern automotive industry market, there have been a lot of state-of-art methodologies to perform a conceptual design of a car; functional methods and 3D scanning technology are widely used. Naturally, the issues frequently boiled down to a trade-off decision making problem between quality and cost. Besides, to incorporate the design method with advanced optimization methodologies such as design-of-experiments (DOE), surrogate modeling, how efficiently a method can morph or recreate a vehicle’s shape is crucial. This paper accomplishes an aerodynamic design optimization of rear shape of a sedan by incorporating a reverse shape design method (RSDM) with the aforementioned methodologies based on CFD analysis for aerodynamic drag reduction. RSDM reversely recovers a 3D geometry of a car from several 2D schematics. The backbone boundary lines of 2D schematic are identified and regressed by appropriate interpolation function and a 3D shape is yielded by a series of simple arithmetic calculations without losing the detail geometric features. Besides, RSDM can parametrize every geometric entity to efficiently manipulate the shape for application to design optimization studies. As the baseline, an Audi A6 is modeled by RSDM and explored through CFD analysis for model validation. Choosing six design variables around the rear shape, 77 design points are created to build neural networks. Finally, a significant amount of CD reduction is obtained and corresponding configuration is validated via CFD.

The aerodynamic resistance to a rotating sphere in the transition régime between free molecule and continuum creep flow

1964 ◽  
Vol 279 (1376) ◽  
pp. 39-49 ◽  
Keyword(s):  
Rarefied Gas ◽  
Aerodynamic Drag ◽  
Aerodynamic Resistance ◽  
Reynolds Numbers ◽  
Approximate Theory ◽  
Drag Torque ◽  
Free Molecule ◽  
Steel Sphere ◽  
Creep Flow ◽  
Wide Range

An experimental and theoretical study has been made of the aerodynamic drag torque on a sphere rotating in a rarefied gas. The drag torque on a magnetically suspended polished steel sphere rotating in air was measured over a wide range of Knudsen numbers from continuum to free molecule flow and for several different Mach numbers up to ca . 1. The drag under free molecule conditions was found to be consistent with the assumption of perfectly diffuse reflexion of molecules at the surface of the rotor. An approximate theory is derived which is analogous to Millikan’s solution to the problem of plane Couette flow and is valid for low Mach and Reynolds numbers. Theory and experiment are found to agree to within 10 % in the range investigated, for Reynolds numbers less than ca . 20.

Lessons to be Learned from the Study of Indigenous Craft

2015 ◽  
Author(s):  
Peter G. Noble
Keyword(s):  
High Performance ◽  
Mark Twain ◽  
Evolutionary Process ◽  
Long Tail ◽  
Scientific Methods ◽  
The Bible ◽  
History Of ◽  
New Ideas ◽  
Naval Architect ◽  
Design Construction

By looking backwards we can often discover solutions that will allow forward progress. We see in the bible the idea that history repeats itself: What has been will be again, what has been done will be done again; there is nothing new under the sun. Ecclesiastes 1:9 But the author subscribes to the idea put forward by the American humorist, Mark Twain: History doesn’t repeat itself, but sometimes it rhymes. The design and construction of water-borne craft using “scientific” methods is a relatively recent development in the context of the whole history of that activity, and is by no means universally applied even today Many traditional craft in current service still rely on the process akin to natural selection, as proposed by Darwin, that is, it is not the strongest, most intelligent nor the fittest that survive but those that best adapt. And the evolutionary process continues today. From Bangkok water taxis with “long-tail” propulsion systems, and from Haitian fishing boats with high performance new sails to whaling umiaks in NW Alaska covered with tensioned membrane skins made from walrus hide and equipped with outboard motors, there can be value in studying the design, construction and operational approaches of these craft. Such consideration can lead to insights for the modern naval architect. A number of well-researched publications (Tapan Adney, 1964) and (Haddon, 1975) give a wealth of information on indigenous craft. Sturgeon Nose Canoe USN ZUMWALT Class Destroyer. Noble Lessons to be learned from the study of indigenous craft 2 Lessons such as optimizing weight/strength ratios, minimizing resistance, utilizing materials in clever ways, developing repairable structures etc., can all be learned from the study of indigenous craft. The sense of continuity with a living past obtained by the study of the work of previous generations of designers and builders, realizing that many current problems were their problems too, is both valuable and satisfying. That said, not all examples given in this paper can be directly linked to designers actively seeking out past developments. Some examples have occurred by coincidence, some by accident and some by unwitting “reinvention of the wheel”. Many “new” ideas, however, have been tried before and it is very often possible to test a new idea against past experience. This paper builds on previous ethno-technical study, (Noble 1994) describing the author’s experience in this field and uses a number of specific examples to illustrate the premise.

scholarly journals Mode-I Fracture Behavior of CFRPs: Numerical Model of the Experimental Results

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 513 ◽  
Author(s):  
Claudia Barile ◽  
Caterina Casavola ◽  
Benedetto Gambino ◽  
Alessandro Mellone ◽  
Marco Spagnolo
Keyword(s):  
Numerical Model ◽  
Composite Laminates ◽  
High Performance ◽  
Mechanical Response ◽  
Numerical Models ◽  
Constitutive Relationship ◽  
Mode I ◽  
Experimental Calibration ◽  
Reinforced Plastics ◽  
High Performance Composite

In the last decades, the increasing use of laminate materials, such as carbon fibre reinforced plastics, in several engineering applications has pushed researchers to deeply investigate their mechanical behavior, especially in consideration of the delamination process, which could affect their performance. The need for improving the capability of the current instruments in predicting some collapse or strength reduction due to hidden damages leads to the necessity to combine numerical models with experimental campaigns. The validation of the numerical models could give useful information about the mechanical response of the materials, providing predictive data about their lifetime. The purpose of the delamination tests is to collect reliable results by monitoring the delamination growth of the simulated in situ cracking and use them to validate the numerical models. In this work, an experimental campaign was carried out on high performance composite laminates with respect to the delamination mode I; subsequently, a numerical model representative of the experimental setup was built. The ANSYS Workbench Suite was used to simulate the delamination phenomena and modeFRONTIER was applied for the numerical/experimental calibration of the constitutive relationship on the basis of the delamination process, whose mechanism was implemented by means of the cohesive zone material (CZM) model.

scholarly journals Conformal Patch Antenna Arrays Design for Onboard Ship Deployment Using Genetic Algorithms

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Stelios A. Mitilineos ◽  
Symeon K. Symeonidis ◽  
Ioannis B. Mpatsis ◽  
Dimitrios Iliopoulos ◽  
Georgios S. Kliros ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Antenna Arrays ◽  
Patch Antenna ◽  
High Performance ◽  
Aerodynamic Drag ◽  
A Priori ◽  
Conformal Antennas ◽  
Antenna Performance ◽  
And Performance ◽  
Aerodynamic Drag Reduction

Conformal antennas and antenna arrays (arrays) have become necessary for vehicular communications where a high degree of aerodynamic drag reduction is needed, like in avionics and ships. However, the necessity to conform to a predefined shape (e.g., of an aircraft’s nose) directly affects antenna performance since it imposes strict constraints to the antenna array’s shape, element spacing, relative signal phase, and so forth. Thereupon, it is necessary to investigate counterintuitive and arbitrary antenna shapes in order to compensate for these constraints. Since there does not exist any available theoretical frame for designing and developing arbitrary-shape antennas in a straightforward manner, we have developed a platform combining a genetic algorithm-based design, optimization suite, and an electromagnetic simulator for designing patch antennas with a shape that is not a priori known (the genetic algorithm optimizes the shape of the patch antenna). The proposed platform is further enhanced by the ability to design and optimize antenna arrays and is intended to be used for the design of a series of antennas including conformal antennas for shipping applications. The flexibility and performance of the proposed platform are demonstrated herein via the design of a high-performance GPS patch antenna.

Experimental investigation of the aerodynamic drag of roof-mounted insulators for trains

2019 ◽  
Vol 234 (8) ◽  
pp. 834-846
Author(s):  
Jonathan Tschepe ◽  
Jörg-Torsten Maaß ◽  
Christian Navid Nayeri ◽  
Christian Oliver Paschereit
Keyword(s):  
Boundary Conditions ◽  
Energy Demand ◽  
High Speed ◽  
Aerodynamic Drag ◽  
Aerodynamic Resistance ◽  
Reynolds Numbers ◽  
Experimental Investigations ◽  
Flexible Material ◽  
High Speed Trains ◽  
The Impact

This paper presents the results of experimental investigations on the aerodynamic drag of roof-mounted insulators for use on low- and high-speed trains. Wind tunnel investigations at different Reynolds numbers in the subcritical, critical, and supercritical flow regime were performed, in addition to investigations using wall-mounted cylinders. Furthermore, the impact of insulator sheds made of flexible material was analyzed. For a better understanding of the aerodynamic behavior of the insulators when mounted on trains, different boundary conditions representing realistic configurations as found on the roof of trains were simulated. From the measured drag, the energy demand to overcome the aerodynamic resistance of different types of insulators was calculated. Depending on the above mentioned boundary conditions, a noticeable contribution of the insulators to the entire train's aerodynamic drag could be observed. With flexible insulator sheds, a further increased air resistance was observed with the onset of fluttering. Similar to the cylinder, the aerodynamic behavior of the insulators depends on the respective Reynolds number.

scholarly journals The inclusion of vehicle shape and aerodynamic drag estimations within the life cycle energy optimisation methodology

Procedia CIRP ◽  
2019 ◽  
Vol 84 ◽  
pp. 902-907
Author(s):  
Hamza Bouchouireb ◽  
Ciarán J. O’Reilly ◽  
Peter Göransson ◽  
Josef-Peter Schöggl ◽  
Rupert J. Baumgartner ◽  
...  
Keyword(s):  
Life Cycle ◽  
Aerodynamic Drag ◽  
Vehicle Shape ◽  
Energy Optimisation

CFD Analysis and Knock Prediction into Crevices of Piston to Liner Fireland of an High Performance ICE

2019 ◽  
Author(s):  
Angelo Rosetti ◽  
Corrado Iotti ◽  
Andrea Bedogni ◽  
Giuseppe Cantore ◽  
Stefano Fontanesi ◽  
...  
Keyword(s):  
High Performance ◽  
Cfd Analysis
Sign in / Sign up

Export Citation Format

Share Document