FORCED CONVECTIVE HEAT TRANSFER ENHANCEMENT BY USING CONICAL RING INSERTS- A REVIEW

Abstract: In the recent years, heat transfer augmentation techniques plays an important role for improving the rate of heat transfer without affecting the overall performance of the system. Enhanced heat transfer surfaces are mostly used in heat exchanger, air conditioner, refrigeration system, chemical reactor. The high cost of energy and material has resulted in an increased effort aimed at producing more efficient heat exchange equipment. Augmentation techniques increase forced convective heat transfer by reducing the thermal resistance in a heat exchanger. These techniques are broadly classified as passive, active and compound techniques. Passive techniques, where inserts are used in the flow path to intensify the heat transfer, are advantageous when compared with active techniques, because the insert manufacturing process is simple and these techniques can be easily employed in an existing heat exchanger. In this paper, emphasis is given to work dealing with round pipe conical ring inserts. Conical ring inserts are generally more efficient in the turbulent flow compared to the laminar flow.

Keywords: Augmentation techniques, forced convective heat transfer, conical ring insert, heat transfer coefficient.