Numerical investigations focused on slit-perforated-fin and wavy-perforated-fin 3-D models were conducted to analyse the flow mechanism and heat transfer characteristics.The simulation results were compared and verified with the existing empirical equations.For the slit-fin
the results indicated that the perforation influenced the flow and temperature fields.Flow resistance increased with increasing aperture size
but heat transfer performance became better first but was improved slightly after the aperture size reached a specific value.For the wavy-fin
the position of perforation was an important factor. Heat transfer performance was better and air side pressure drop was greater with aperture on the wave-crest than the case with aperture on the wave-middle.