Abstract
Experiments have been performed for a turbulent channel flow obstructed by two parallel triangular cylinders in tandem arrangement. The triangular cylinder of two kinds of the angle is used. The first and second triangular cylinders are same shape. The clearance between the wall and the triangular cylinder is changed in three steps. The distance between two triangular cylinders is varied from 80mm to 300mm. The particle image velocimetry (PIV) has been applied to measure the fluid flow around the triangular cylinder. When the clearance is small (S=1mm), local Nuseelt number becomes large just under the second cylinder. At the large clearance (S=5mm), the vortex shedding is observed at the first cylinder, however, it disappear at the second cylinder.
