To match the rotor blade of real engine operating condition,the Reynolds and rotation number range of current experiment were expanded from 10 000 to 70 000 and 0to2.08 by increasing the pressure of the air in the U-shaped channel to 500 kPa.Experiments were conducted to investigate the heat transfer characteristics in a square U-shaped channel with inclined 45 deg ribs.Results indicated that,in the first passage of the U-shaped channel,heat transfer coefficient of leading wall firstly decreased with the in...