Numerical fluid flow analysis for aerodynamic characteristics of a rectangular cylinder

This study has focused on characteristics of an negative slope of lift coefficient curve on a reattachment type rectangular cylinder that is side ratio 4. Based on the result of wind tunnel test, the slope of the lift coefficient curve was positive as far as attack angle 4 degree. And this trend changes to negative from 4 degree to 8 degree. As for this negative slope, the stability problems for wind-resistant forces come into question frequently. In order to clarify the cause of the negative slope of lift coefficient curve, the CFD was tried to introduce. Three dimensional numerical analyses of the flow around a rectangular cylinder with α were carried out by means of the IBTD/FS finite element method without any turbulence model. A reproduction of negative slope of lift coefficient curve was succeeded in this paper.