The convective heat transfer performance of converging-diverging plate channels with fin-wall perforations is computationally modeled. Covering a Reynolds Number range of 10 < Re < 1000 for air (Pr = 0.72) flows, a parametric study of the effect of the two dimensional duct geometry, which has symmetric fin wall corrugations of trapezoidal profile, are considered. The geometric variables are described by the divergent-plane’s inclination angle φ and the convergent-divergent amplitude ratio α. The wall perforations are modeled as uniformly distributed equi-size thin slots so as to render a porosity (ratio of perforated are to total surface area) β of 10% on the fin surface. The fin-wall transpiration (fluid injection in the divergent section and fluid suction in the convergent section) is seen to promote enhanced convective heat transfer by inducing cross stream mixing and periodic disruption of the boundary layer. As a result, the thermal-hydraulic performance is found to be characteristically unusual, where increase in heat transfer is accompanied with a reduction in frictional loss. The enhanced performance evaluated by both area goodness and volume goodness measures, is seen to render a substantially more compact heat exchanger.

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