Drag Coefficient of the Crossed Two Circular Cylinders

Measurements were made of the surface pressure distributions and drag coefficient for two circular cylinders forming a cross with low blockage ratio and high aspect ratio. The results showed that integrated drag coefficient was smaller than that of two-dimentional circular cylinder over a range of a Reynolds number from (10)^3 to 8×(10)^3. The local drag coefficient of upstream cylinder at the location of about y/d=1 was larger than that of a single cylinder by 25%. On the other hand the local drag coefficient of downstream cylinder took the minimum value at about z/d=0.2.