Turbulent forced convective heat transfer and flow configurations in a square channel with wavy-ribs inserted diagonally are examined numerically. The influences of the 30° and 45° flowattack angles forwavy-ribs

blockage ratio

R

B

=b/H=0.05-0.25with single pitch ratio

R

P

=P/H=1 are investigated for the Reynolds number based on the hydraulic diameter of the square channel

Re=3000-20000. The use of the wavy-ribs

which inserted diagonal in the square channel

is aimed to help to improve the thermal performance in heat exchange systems. The finite volume method and SIMPLE algorithm are applied to the present numerical simulation. The results are presented on the periodic flow and heat transfer profiles

flow configurations

heat transfer characteristics and the performance evaluations. The mathematical results reveal that the use of wavy-ribs leads to a higher heat transfer rate and friction loss over the smooth channel. The heat transfer enhancements are around 1.97-5.14 and 2.04-5.27 times over the smooth channel for 30° and 45° attack angles

respectively. However

the corresponding friction loss values for 30° and 45° are around 4.26-86.55 and 5.03-97.98 times higher than the smooth square channel

respectively. The opt

imumthermal enhancement factor on both cases is found at R

B

=0.10 and the lowest Reynolds number

Re=3000

to be about 1.47 and 1.52

respectively

for 30° and 45° wavy-ribs.