Heart Transfer in High Aspect Ratio Rectangular Passage with Skewed Ribs

Abstract

The heat transfer characteristics and flow behavior in a rectangular passage with two opposite 45°skewed ribs for turbine rotor blade have been investigated for Reynolds numbers from 7800 to 19000. In this blade, the spanwise coolant passage at the trailing edge region whose thickness is very thin is chosen, so the channel aspect ratio(=width/height of channel)is extremely high, 4.76. Therefore the heat transfer experiment in the high aspect ratio cooling channel was performed using thermochromic liquid crystal and thermocouples. Furthermore the calculation of flow and heat transfer was carried out using CFD analysis code to understand the heat transfer experimental results. The enhanced heat transfer coefficients on the smooth side wall at rib leading end were the same level as those on the rib roughened walls.