INTERFERENCE EFFECTS ON THE AVERAGE WIND PRESSURE AND AVERAGE DRAG FORCE IN TANDEM THREE CIRCULAR CYLINDERS

To provide a reference for the wind load of a tandem three circular cylinders structure in an actual engineering project, 12 different spacing ratios L/D were tested by using a rigid model pressure wind tunnel test method, where L is the distance between the centers of two circular cylinders and D is the diameter of the circular cylinder. The average wind pressure coefficient and average drag force coefficient of the three circular cylinders in series were compared with the average wind pressure coefficient and average drag force coefficient of a single circular cylinder. The results show that there are critical spacings in the tandem three circular cylinders, and the critical spacing ratio is 3.0≤L/D≤3.5. The average drag force of the three circular cylinders is smaller than that of a single circular cylinder. The average drag force of the upstream circular cylinder is the largest, that of the downstream circular cylinder is the second largest, and that of the middle circular cylinder is the smallest.