Heat transfer enhancement in concentric tube heat exchanger with tangential injection and twisted tape inserts

Abstract

Heat exchanger has many engineering applications such as air conditioning, chemical reactor and refrigeration systems, etc. The performance of this industries mainly depends on the performance of heat exchanger. So, to increase the performance of heat exchanger many techniques have been investigated on enhancement of heat transfer rate and decrease the size and cost of the heat exchangers. In most of applications and key areas like power plants, process & chemical industries uses surface enhancement methods. Present work mainly emphasis on the both passive and active methods of heat transfer enhancement. In this work, to enhance the heat transfer rate with the help of twisted tape insert in passive method in which aluminium twisted tapes are used. In the active method fluid is injected in annulus space to generate turbulence through tangential injectors. There are six injectors are used to generate turbulence. Water is used as a working fluid in both types of heat exchanger. From the experiment it shows that, as Reynolds number increases heat transfer coefficient also increases