Research Of The Automobile Wind Resistance Characteristic Based On NURBS Surface

Automotive molding design has an important position in the automobile design.How to improve the modelling of the car to further reduce automobile fuel consumption has been a unremitting pursuit by car designers.Automotive molding line is very complex,it contains straight line,conic,and the free curve.At the same time,the wind resistance coefficient is affected by the curve.In ordinary cases of automobile CFD simulation,a three-dimensional model of the molding gets large amount of data,calculation,and it is difficult to intuitively reflect the change of model line to the influence of wind resistance.The CFD simulation using a two-dimensional grid will be more easy and simplified.Therefore,how to quickly and efficiently extract the car cross section contour curve,and be used in automobile CFD simulation by two-dimensional is of great significance.Main research contents are as follows:(1)The development and influence about automobile design and aerodynamic;(2)The research on NURBS curve,NURBS Surface and RhinoScript editor from Rhinoceros;(3)Using GAMBIT and FLUENT to establish two-dimensional and three-dimensional car flow field figure;(4)Qualitative and quantitativeContrast two-dimensional flow field and three-dimensional flow field of velocity diagram file to verify the feasibility of the method in this paper.