Modified k-ε model Aerodynamic properties of rectangular cylinders having infinite spanwise length with various breadth/depth ratio ranging from B/D=0.6 to 8.0 were investigated numerically by two-layer k-ε model with modification on k-production term. Although present numerical approach is two-dimensional, a physically reasonable smooth periodic vortex shedding was obtained even in the range of high Reynolds number, which can not be simulated by the ordinary simple 2D analysis which is not incorporated with any turbulence model. Various typical aerodynamic features were successfully obtained particularly including discontinuity in Strouhal number at critical section of B/D=2.8 and 6.0. Also, for various B/D ratios, drag coefficients and mean surface pressure distribution were in good agreement with experiments and three-dimensional analysis. However, for the prediction of fluctuation in pressure and forces, since the periodic component can only be taken into account by RANS model and due to lack of its ability to assess the stochastic component, total fluctuation in surface pressure and aerodynamic lift force were considerably underestimated in some cases compared with experiments and 3D analysis.
