Particle Image Velocimetry Study and Numerical Simulation of Turbulent near Wake of Square Cylinder

Abstract:

The result of the experiment of vortex shedding from a square cylinder is important in comparing the precision of different models including Reynolds averaged Navior Stokes(RANS) models in computational fluid dynamics(CFD). The experiment of vortex shedding from a square cylinder with the Reynolds number of 2.2×104 is done using particle image velocimetry (PIV). A comparison with the results of Laser Doppler Velocimetry(LDV) experiments carried out by other researchers in the same Reynolds number shows that the PIV instruments is effective in obtaining turbulent wake of bodies. Comparisons are also conducted with different RANS models(Realizable k-ε model，k-ω shear stress transport(SST) model and Reynolds stress model) of the coefficients of damping ratio,strouhal number and the velocity profiles and turbulent kinetic energy profiles. It is discovered that the result of the k-ω SST model is much more precise in the aerodynamic parameter identification and flow field simulation mentioned above.

Key words:square cylinder; Reynoids averaged Navior Stokes model; particle image velocimeting; damping coefficient; Strouhal number; turbulent kinetic energy