CFD Investigations of the Effect of Rotating Wheels, Ride Height and Wheelhouse Geometry on the Drag Coefficient of Electric Vehicle

Drag Coefficient ◽

Electric Vehicles ◽

Aerodynamic Drag ◽

Design Parameters ◽

Ride Height ◽

Full Vehicle ◽

Maximum Range ◽

The development of electric vehicles demands minimizing aerodynamic drag in order to provide maximum range. The wheels contribute significantly to overall drag coefficient value because of flow separation from rims and wheel arches. In this paper various design parameters are investigated and their influence on vehicle drag coefficient is presented. The investigation has been done with the help of computational fluid dynamics (CFD) tools and with implementation of full vehicle setup with rotating wheels. The obtained results demonstrate changes in drag coefficient with respect to the change of design parameters.

Aerodynamic Analysis of a Vehicle Tanker

Journal of Fluids Engineering ◽

10.1115/1.3077135 ◽

2009 ◽

Vol 131 (4) ◽

Cited By ~ 5

Author(s):

Ramon Miralbes Buil ◽

Luis Castejon Herrer

Keyword(s):

Fluid Dynamics ◽

Drag Coefficient ◽

Aerodynamic Drag ◽

Positive Impact ◽

Aerodynamic Resistance ◽

Independent Contribution ◽

Aerodynamic Drag Coefficient ◽

Selection Of

The aim of this article is the presentation of a series of aerodynamic improvements for semitrailer tankers, which reduce the aerodynamic resistance of these vehicles, and, consequently, result in a positive impact on fuel consumption, which is substantially reduced (up to 11%). To make the analysis the computational fluid dynamics (CFD) methodology, using FLUENT, has been used since it allows simulating some geometries and modifications of the geometry without making physical prototypes that considerably increase the time and the economical resources needed. Three improvements are studied: the aerodynamic front, the undercarriage skirt, and the final box adaptor. First they are studied in isolation, so that the independent contribution of each improvement can be appreciated, while helping in the selection of the most convenient one. With the aerodynamic front the drag coefficient has a reduction of 6.13%, with the underskirt 9.6%, and with the boat tail 7.72%. Finally, all the improvements are jointly examined, resulting in a decrease of up to 23% in aerodynamic drag coefficient.

Volume 2: Thermal Management; Data Centers and Energy Efficient Electronic Systems ◽

Combining Computational Fluid Dynamics (CFD) and Flow Network Modeling (FNM) for Design of a Multi-Chip Module (MCM) Cold Plate

10.1115/ipack2013-73294 ◽

2013 ◽

Cited By ~ 3

Author(s):

John Fernandes ◽

Saeed Ghalambor ◽

Akhil Docca ◽

Chris Aldham ◽

Dereje Agonafer ◽

...

Keyword(s):

Fluid Dynamics ◽

Thermal Analysis ◽

Network Modeling ◽

Computational Time ◽

Design Parameters ◽

Cold Plate ◽

Original Solution ◽

Flow Network ◽

The objective of the study is to improve on performance of the current liquid cooling solution for a Multi-Chip Module (MCM) through design of a chip-scale cold plate with quick and accurate thermal analysis. This can be achieved through application of Flow Network Modeling (FNM) and Computational Fluid Dynamics (CFD) in an interactive manner. Thermal analysis of the baseline cold plate design is performed using CFD to determine initial improvement in performance as compared to the original solution, in terms of thermal resistance and pumping power. Fluid flow through the solution is modeled using FNM and verified with results from the CFD analysis. In addition, CFD is employed to generate flow impedance curves of non-standard components within the cold plate, which are used as input for the Hardy Cross method in FNM. Using the verified flow network model, design parameters of different components in the cold plate are modified to promote uniform flow distribution to each active region in the chip-scale solution. Analysis of the resultant design using CFD determines additional improvement in performance over the original solution, if available. Thus, through complementary application of FNM and CFD, a robust cold plate can be designed without requiring expensive fabrication of prototypes and with minimal computational time and resources.

Evaluation of Heat Transfer Performance of a Multi-Disc Sorption Bed Dedicated for Adsorption Cooling Technology

Energies ◽

10.3390/en12244660 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4660 ◽

Cited By ~ 5

Author(s):

Marcin Sosnowski

Keyword(s):

Heat Transfer ◽

Fluid Dynamics ◽

Heat Transfer Performance ◽

Design Parameters ◽

Transfer Performance ◽

Sorption Model ◽

Factors Influencing ◽

Cooling Technology

The possibility of implementing the innovative multi-disc sorption bed combined with the heat exchanger into the adsorption cooling technology is investigated experimentally and numerically in the paper. The developed in-house sorption model incorporated into the commercial computational fluid dynamics (CFD) code was applied within the analysis. The research allowed to define the design parameters of the proposed type of the sorption bed and correlate them with basic factors influencing the performance of the sorption bed and its dimensions. The designed multi-disc sorption bed is characterized by great scalability and allows to significantly expand the potential installation sites of the adsorption chillers.

Investigation of Influence of Adjustments in Cyclist Arm Position on Aerodynamic Drag Using Computational Fluid Dynamics

Proceedings ◽

10.3390/proceedings2020049159 ◽

2020 ◽

Vol 49 (1) ◽

pp. 159

Author(s):

Knut Erik Teigen Giljarhus ◽

Daniel Årrestad Stave ◽

Luca Oggiano

Keyword(s):

Fluid Dynamics ◽

Aerodynamic Drag ◽

Time Trial ◽

Elbow Extension ◽

Cfd Simulations ◽

Arm Position ◽

Sport Activities ◽

The Face ◽

In professional cycling, even small adjustments in position could mean that valuable seconds are gained over the course of a time-trial race. This study investigates the influence of arm position on the aerodynamic drag of a cyclist. Based on a 3D scanned model of a professional cyclist, 64 alternate positions are generated. The parameters that are investigated are the distance between elbows, elbow extension, and distance between hands. Computational fluid dynamics (CFD) simulations of all positions are performed, and a regression model is built from the results. The results indicate that the optimal posture is achieved for a minimum in all investigated parameters, which means that the hands and elbows should be kept together with hands up towards the face. Furthermore, elbow extension seems to be the most crucial parameter, followed by the distance between elbows, and then by the distance between the hands. The presented methodology can be applied to study other parameters relevant to cycling aerodynamics or be applied to other sport activities as well.

Volume 1A, Symposia: Advances in Fluids Engineering Education; Advances in Numerical Modeling for Turbomachinery Flow Optimization; Applications in CFD; Bio-Inspired Fluid Mechanics; CFD Verification and Validation; Development and Applications of Immersed Boundary Methods; DNS, LES, and Hybrid RANS/LES Methods ◽

Computational Fluid Dynamics (CFD) Analysis of a Single-Stage Downhole Turbine

10.1115/fedsm2013-16258 ◽

2013 ◽

Author(s):

Rajani Satti ◽

Narasimha Rao Pillalamarri ◽

Eckard Scholz

Keyword(s):

Fluid Dynamics ◽

Three Dimensional ◽

Operating Regime ◽

Single Stage ◽

Tip Clearance ◽

Performance Characteristics ◽

Design Parameters ◽

Complex Flow ◽

In this study, the application of computational fluid dynamics (CFD) is explored to predict the performance characteristics in a typical single-stage downhole turbine. The single-stage turbine model utilized for this study consists of a stator and a rotor. A finite-volume based CFD approach was implemented to simulate the complex flow field around the turbine. The analysis is based on transient, three-dimensional, isothermal turbulent flow in an incompressible fluid system. The inlet flow rates and angular velocity of the rotor were varied to encompass the operating regime. Comparison with experimental data revealed excellent agreement, proving reliability of the model in predicting the performance characteristics. Motivated by the successful model validation, a parametric study (considering blade tip clearance and blade count) was also conducted to understand the effects of the design parameters on the performance of the turbine. Detailed flow visualizations and efficiency calculations were also done to provide further insight into the overall performance of the turbine. As part of the present study, significant efforts were also spent in the following areas: standardization of CFD methodology and assessment of commercial software to develop an integrated CFD-driven design process.

STUDY OF MESH REFINEMENT ON THE AERODYNAMIC COEFFICIENTS FOR NACA2412 PROFILE WITH DIFFERENT ANGLE OF ATTACK AND k - w TURBULENCE MODEL

Revista Mundi Engenharia Tecnologia e Gestão (ISSN 2525-4782) ◽

10.21575/25254782rmetg2020vol5n21141 ◽

2020 ◽

Vol 5 (2) ◽

Author(s):

Nícolas Lima Oliveira ◽

Eric Vargas Loureiro ◽

Patrícia Habib Hallak

Keyword(s):

Fluid Dynamics ◽

Drag Coefficient ◽

Turbulence Model ◽

Lift Coefficient ◽

Mesh Refinement ◽

Angle Of Attack ◽

Aerodynamic Coefficients ◽

This work presents the studies obtained using OpenFOAM OpenSource Computational Fluid Dynamics (CFD) Software. Experiments were performed to predict lift coefficient and drag coefficient curves for the NACA2412 profile. Subsequently, the results obtained were compared with the results of the bibliography and discussed.

Dynamic Instability Analysis of a Spring-Loaded Pressure Safety Valve Connected to a Pipe by Using Computational Fluid Dynamics Methods

Journal of Pressure Vessel Technology ◽

10.1115/1.4049697 ◽

2021 ◽

Vol 143 (4) ◽

Author(s):

Fengjie Zheng ◽

Chaoyong Zong ◽

Chao Zhang ◽

Xueguan Song ◽

Fuzheng Qu ◽

...

Keyword(s):

Fluid Dynamics ◽

Dynamic Instability ◽

Design Parameters ◽

Wave Forces ◽

Cfd Model ◽

Pressure System ◽

System Pressure ◽

And Performance

Abstract As the ultimate protection of a pressure system, pressure safety valves (PSV) can respond in an unstable manner in the form of flutter and chatter, which will affect service life, reliability, and performance. In order to study the dynamic instability caused by multisource forces including the flow force, the spring compression force, and the pressure wave forces, a high-fidelity computational fluid dynamics (CFD) model of the system is proposed. A complete CFD model, incorporating the PSV, connected pipes, and the pressure vessel, is developed, in which advanced techniques in Fluent using User Defined Function (UDF) and Dynamic Layering method are combined to allow the PSV to be coupled to the system dynamics. Based on this model, the valve's opening and reclosing process is monitored to examine the influence of design parameters on the dynamic instability of the PSV. Specifically, the propagation of pressure waves along the connecting pipes is successfully captured, helping to assess the instability mechanism and provide the ability to optimize the design and setup of pressure relief systems.

Hydrodynamic Analysis of Different Finger Positions in Swimming: A Computational Fluid Dynamics Approach

Journal of Applied Biomechanics ◽

10.1123/jab.2013-0296 ◽

2015 ◽

Vol 31 (1) ◽

pp. 48-55 ◽

Cited By ~ 6

Author(s):

J. Paulo Vilas-Boas ◽

Rui J. Ramos ◽

Ricardo J. Fernandes ◽

António J. Silva ◽

Abel I. Rouboa ◽

...

Keyword(s):

Fluid Dynamics ◽

Drag Coefficient ◽

Hydrodynamic Force ◽

Lift Coefficient ◽

Flow Speed ◽

Cfd Analysis ◽

Mean Flow ◽

Hydrodynamic Analysis ◽

The aim of this research was to numerically clarify the effect of finger spreading and thumb abduction on the hydrodynamic force generated by the hand and forearm during swimming. A computational fluid dynamics (CFD) analysis of a realistic hand and forearm model obtained using a computer tomography scanner was conducted. A mean flow speed of 2 m·s−1was used to analyze the possible combinations of three finger positions (grouped, partially spread, totally spread), three thumb positions (adducted, partially abducted, totally abducted), three angles of attack (a = 0°, 45°, 90°), and four sweepback angles (y = 0°, 90°, 180°, 270°) to yield a total of 108 simulated situations. The values of the drag coefficient were observed to increase with the angle of attack for all sweepback angles and finger and thumb positions. For y = 0° and 180°, the model with the thumb adducted and with the little finger spread presented higher drag coefficient values for a = 45° and 90°. Lift coefficient values were observed to be very low at a = 0° and 90° for all of the sweepback angles and finger and thumb positions studied, although very similar values are obtained at a = 45°. For y = 0° and 180°, the effect of finger and thumb positions appears to be much most distinct, indicating that having the thumb slightly abducted and the fingers grouped is a preferable position at y = 180°, whereas at y = 0°, having the thumb adducted and fingers slightly spread yielded higher lift values. Results show that finger and thumb positioning in swimming is a determinant of the propulsive force produced during swimming; indeed, this force is dependent on the direction of the flow over the hand and forearm, which changes across the arm’s stroke.

Aerodynamics Analysis of Speed Skating Helmets: Investigation by CFD Simulations

Applied Sciences ◽

10.3390/app11073148 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3148

Author(s):

Guillermo Puelles Magán ◽

Wouter Terra ◽

Andrea Sciacchitano

Keyword(s):

Fluid Dynamics ◽

Flow Field ◽

Numerical Simulations ◽

Turbulence Model ◽

Aerodynamic Drag ◽

Cfd Simulations ◽

Speed Skating ◽

Rans Simulations

In this work, we investigate the flow field around speed skating helmets and their associated aerodynamic drag by means of computational fluid dynamics (CFD) simulations. An existing helmet frequently used in competition was taken as a baseline. Six additional helmet designs, as well as the bare-head configuration, were analysed. All the numerical simulations were performed via 3D RANS simulations using the SST k-ω turbulence model. The results show that the use of a helmet always reduces the aerodynamic drag with respect to the bare head configuration. Besides, an optimised helmet design enables a reduction of the skaters aerodynamic drag by 5.9%, with respect to the bare-head configuration, and by 1.6% with respect to the use of the baseline Omega helmet.

Reduced Aerodynamic Drag for Truck-Trailer Configurations Using Parametrized CFD Studies

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-86816 ◽

2012 ◽

Cited By ~ 1

Author(s):

Srdan Pavlović ◽

Magnus Andersson ◽

Jonas Lantz ◽

Matts Karlsson

Keyword(s):

Fluid Dynamics ◽

Drag Reduction ◽

Conceptual Design ◽

Fuel Economy ◽

Aerodynamic Drag ◽

Foreseeable Future ◽

Heavy Duty ◽

In the presented work, two studies using Computational Fluid Dynamics (CFD) have been conducted on a generic truck-like model with and without a trailer unit at a speed of 80 km/h. The purpose is to evaluate drag reduction possibilities using externally fitted devices. A first study deals with a flap placed at the back of a rigid truck and inclined at seven different angles with two lengths. Results show that it is possible to decrease drag by 4%. In a second study, the flap has been fitted on the tractor and trailer units of a truck-trailer combination. Four settings were surveyed for this investigation, one of which proved to decrease drag by up to 15%. A last configuration where the gap between the units has been closed has also been evaluated. This configuration offers a 15% decrease in drag. Adding a flap to the closed gap configuration decreases drag by 18%. New means of reducing aerodynamic drag of heavy-duty (HD) vehicles will be important in the foreseeable future in order to improve the fuel economy. The possibilities of reducing drag are prevalent using conceptual design.