To match the real engine operating condition

Reynolds number and rotation number range of current experiment were expanded from 10000 to 70000 and 0 to 2.08 by increasing the air pressure. Experiment was conducted to investigate the heat transfer characteristics in a square two-pass channel with inclined 45 degree ribs

and three different channel angles (0 degree

22.5 degree

45 degree) were selected to study the effect of channel angle on heat transfer characteristics. Results indicate that in the first channel

channel angle has a larger effect on trailing wall than leading wall

especially near the inlet of the channelin the second channel

channel angle has a smaller effect on both trailing wall and leading wall. To the region average heat transfer distribution

the 45 degree channel is higher than other channels (0 degree

22.5 degree)

and 0 degree channel is the lowest.