Heat transfer enhancement in heat exchanger by using passive approach has become a very versatile area of research for the researchers. Although very significant results has been achieved in the thermal performance of heat exchangers, especially in the range of lower Reynolds number, but still these passive approaches of heat transfer enhancement is not effective for the range of higher Reynolds number. In the present work the effect of 'perforated circular disk turbulators with and without twisted tape', on heat transfer, friction factor and thermal performance of heat exchanger is evaluated experimentally. The different geometrical parameters used for the experiment include fixed diameter ratio (0. 8), pitch ratios (1, 2, and 3), perforation index (0%, 8%, 16%, and 24%), fixed twist ratio (2) and fixed width ratio (0.4). The experiment is done in the range of Reynolds number lying from 6,500 to 26,500. On the basis of experimental observation, there is 2.2-3.54 times improvement in heat transfer and around 1.18-1.64 times improvement in thermal performance factor over smooth tube heat exchanger.