In order to simulate the flow and heat transfer in a turbine coolant channel

grids were used to control the turbulent intensity in a smooth channel. Different sizes of grids were used to generate different turbulence intensity. In the experiment

three different kinds of grids were put in a square smooth channel with the cross-section of 80mm×80mm. Hot-wire was used to measure the turbulence with Reynolds ranging from 5000 to 30000. The results showed that after flowing through the grids

the turbulent intensity can be up to 4.5%

and decreased along the stream-wise directions. The effect of Reynolds numbers on turbulent intensity is not obvious in the current work. And the turbulent integral time scale has a positive relationship with Reynolds numbers.