Fluid Force And Pressure Acting On Two Staggered Square Cylinders

Along with the social and economic rapid development,the constant advance of industrialization and technology,many buildings become higher and higher all over the world.Especially,In the applications of practical engineering,it is very important for the safety of prism structure that exposed in the flow field.Then,research on the mechanism of the interference and the characteristics of aerodynamic force between two cylinders is of great importance.The square cylinder is one of a most common types of blunt body in the aerodynamics,and most often used in the practical engineering.So research on flow structure and the characteristics of aerodynamic force between two staggered square cylinders is of great significance.This thesis studied in the wind tunnel at a Reynolds number Re = 1.3 × 104.It aims to provide a systematic experimental study of the wake flow structure and the characteristics of aerodynamic force behind two staggered square cylinders at different spacing ratio(P* = 1.5 ~ 5)and different angle(? = 0° ~ 90°).Form the experimental data,we can analysis of how it changes with arrangement.In this project,we supplement the four main flow regime(One vortex street:S-?,S-?;Two vortex street: T-?,T-?)with aerodynamic force and redefine the border of each of them.Regime S-?,S-?,T-? are further divided into two sub-regimes(S-?a,S-?b,S-?a,S-?b,T-?a,T-?b)respectively.Base on the difference of position that the shear layer from upstream cylinder reattached.Regime S-?a is more further divided into two parts(S-?a-side: the reattachment position on the side surface of downstream square cylinder;S-?a-windward: the reattachment position on the windward surface of downstream cylinder).This thesis mainly talked about how the flow structure interact between two square cylinders and why the aerodynamic force of two square cylinders changes with arrangement in each flow regime.Meanwhile,we analysed the mechanism of the interference between two square cylinders and find the optimal configuration of arrangement,then it can apply to the practical engineering conveniently.