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Use of cfd in aerodynamic performance of race car

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computational fluid dynamics gives you very complex analysis results. The methodology of use of cfd in race car is given here.

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Use of cfd in aerodynamic performance of race car

  1. 1. What is CFD?? • Computational Fluid Dynamics is “a wind tunnel in the computer.” • It is a method by which one uses certain algorithms or other numerical formulas to analyze the fluids' flow. • We can say it is the smoke profile made in computer.
  2. 2. aPPLiCatiONsaPPLiCatiONs  Biomedical  Electronics  Defense  Industrial  Environmental  Automobiles  Submarines
  3. 3. ExamPLEs OF aPPLiCatiONs OF CFDExamPLEs OF aPPLiCatiONs OF CFD
  4. 4. Why it is NECEssary??  To improve product performance & quality.  To Reduce development costs.  To Reduce lead-times and “time-to-market”  To get optimal results.  CFD software is portable, easy to use.  We can modify the geometry if not satisfied with the results.  Simulations are parallel and multiple-purpose.
  5. 5. VariOus CFD sOFtWarEsVariOus CFD sOFtWarEs  FLUENT  EasyCFD_G  Parallel FEM  ANSYS CFX  FLOW-3D  Passage  NUMECA  CFDesign  FlowEFD  CFD-RC  Phoenics  OpenFOAM  STATCD  Flagship CFD
  6. 6. AerodynAmic efficiency Aerodynamicists measure three variables-  downforce  drag  balance
  7. 7. How does it works?  The analysis begins with building the computer simulated model of a physical problem.  Conservation of matter, momentum, and energy must be satisfied throughout the region of interest.  Fluid and model properties are defined.  Simplifying assumptions are made in order to make the problem tractable (e.g., steady-state, incompressible, two-dimensional).  Initial and boundary conditions are provided.  The computer software divide geometric structure into specific cells or grids.  The set of algebraic equations are solved numerically to calculate the quantities on each of the cell.  The resulting data is used to compute the quantities of interest (like- mass, momentum, pressure, lift, drag etc.) and effects of all of these on the model
  8. 8. unstructured computational mesh (5 million cells) Computer simulated model of ship
  9. 9. - The higher number of cells, gives more accurate results. - CFD also concern with the ignition process of gasoline in order to create power. - It gives Simulations of hot exhaust gases, engine cooling, brake heating/cooling events, tire deformations, and fuel filling and sloshing. How does it works?
  10. 10. mesHing  Domain is discretized into a finite set of control volumes or cells. This process is called as meshing.  The meshing is classified in two main groups- Unstructured meshing Structured meshing
  11. 11. mesHing  The structured meshing is again then classified into following sub-types- triangle quadrilateral tetrahedron pyramid prism or wedgehexahedron arbitrary polyhedron  For simple geometries, quadrilateral or hexahedron meshes can provide high-quality solutions with fewer cells.  For complex geometries, quadrilateral or hexahedron meshes show no numerical advantage, and you can save meshing effort by using a triangular or tetrahedron meshes.
  12. 12. Compute the solution The discretized conservation equations are solved iteratively. A number of iterations are usually required to reach a converged solution. Convergence is reached when: Changes in solution variables from one iteration to the next are negligible. Residuals provide a mechanism to help monitor this trend. Overall property conservation is achieved. The accuracy of a converged solution is dependent upon: Appropriateness and accuracy of the physical models. Grid resolution and independence. Problem setup.
  13. 13. superComputers  BMW Sauber F1 Team- Albert series.  Renault F1 team- Mistral  Force India Formula One Team- eka  Products by CRAY supercomputers.
  14. 14. post-proCessingpost-proCessing Results are usually reviewed in one of two ways. Graphically or Alpha-numerically.  Graphically: – Vector plots. – Contours. – Iso-surfaces. – Flow lines. – Animation. • Alpha-numerics: – Integral values. – Drag, lift, torque calculations. – Averages, standard deviations. – Minima, maxima. – Compare with experimental data. Contours of static pressure
  15. 15. BoB tailing
  16. 16. CFD proCess
  17. 17. aDvantages  It improves the aerodynamic efficiency and capability of racecar.  It enhance the understanding of how various designs will perform.  The more experiments are done in shorter amount f time.  It is capable of analyzing overtaking conditions.  Gives Better fuel economy & limit CO2 emissions.
  18. 18. Overtaking cOnditiOns..
  19. 19. LimitatiOns  The millions of calculations are required to be done to get the result.  It is very complex.  It's not 100% effective.
  20. 20. cOncLusiOn  In this way, we can conclude that the Use of CFD is very essential in the design of racecar.  It has many advantages and it also saves time and money.  It reduces human efforts with improved efficiency.
  21. 21. references  Supercomputing in F1 – Unlocking the Power of CFD (2005) http://www.ansys.com/industries/automotive/TPL10715.pdf  Motor Sport Drives CFD Technology to a New Level(2008) http://www.fluent.com/solutions/sports/tn272.pdf  Computational Fluid Dynamics in Formula 1 Design (1999) http://usuarios.multimania.es/motorformula1/Dinamica_de_Flui dos_en_Formula_1.pdf  How Does CFD Work? (5th may 2009) http://www.autoevolution.com/news/how-does-cfd- computational-fluid-dynamics-work-6400.html))