Heat Transfer Enhancement Techniques are commonly used nowadays in all Thermal industries, where there is heat transfer in the thermal system. Number of new techniques were discovered and studied by various researchers for heat transfer augmentation including both active and passive methods. But emphasis was given for passive techniques of heat transfer enhancement as they directly affect operating cost. The most widely used passive techniques like twisted tape inserts, wire coil insert and conical inserts are focused in this paper. One of the aims of studying various heat transfer enhancement techniques is to assess the effect of an inherent conditions on heat transfer and recommend most effective technique for laminar & turbulent flows. One of the conclusions of the study is twisted tape inserts are better for laminar flow & conical inserts will be more suitable for turbulent region.

Key words: Heat transfer enhancement, passive techniques, twisted tape, wire coil inserts, conical inserts