This study is to experimentally investigate the heat transfer enhancement by perforation in air cooling of
two in-line rectangular heat sources module. Two separation distances between the heat sources were
investigated at s/L = 0.5 and 1.0. The area between the heat sources in both cases were perforated in
aligned arrangement such that the holes open area ratio (b) are of 0, 0.0736, 0.1472 and 0.2944. The
dimensionless temperature distribution and the average Nusselt number are considered at different values
of Reynolds number (3391 6 ReL 6 10798) and holes open area ratio. It could be seen that perforation
could enhance the heat transfer coefficients and reduce the module temperature significantly. Correlations
are obtained for the average Nusselt number utilizing the present measurements within the investigated
range of the different parameters.