The heat exchanger is a thermal device use for heat exchange between higher fluid<br />temperature to lower fluid temperature. Growing need to improve the heat exchangers<br />effectiveness and develop a broad range of investigations for enhancement heat transfer rate<br />along with minimizing the size and cost of the industrial apparatus accordingly. The purpose<br />of the present work to review the articles that related to major types of double pipe heat<br />exchanger and factor effect on heat transfer rate and pressure drop the double pipe heat<br />exchanger considers one of the apparatuses which are used in among industries. Researchers<br />proposed several models of double pipe heat exchanger heat exchangers. Double pipe heat<br />exchangers are used in many industrial processes, cooling technology, refrigeration device,<br />sustainable energy applications and another field. Different classification of Double pipe heat<br />exchangers includes parallel, counter and cross flow. Research operate were also conducted to<br />improve the effectiveness of Double pipe heat exchangers by using turbulators, inserts, rips at<br />both ends, modifying the geometry of channels, methods of injection fluids and, etc. This study<br />reported various research works of Double pipe heat exchangers research works in a technique<br />to satisfy the right effectiveness deciding parameter. <br /><br />for more details, please visit the link inserted below<br />https://iopscience.iop.org/article/10.1088/1742-6596/1973/1/012013/pdf