**Abstract**

The fundamentals of heat transfer and its applications, the classification of heat transfer technology and different heat transfer techniques, and the needs for augmentation and its benefits and the different combinations of two or more inserts and integral roughness elements for heat transfer augmentation purpose have been introduced and discussed in this chapter. It is shown that most of the compound techniques performed better than the individual inserts for heat transfer enhancement. This chapter has also been dedicated to understanding the basic concepts of vortex generators for heat transfer enhancement in plate-fin heat exchangers. The performance of transverse, longitudinal, and wing-type vortex generators has been discussed as well.

**Keywords:** heat transfer, review, enhancement, heat exchanger, vortex generators, twisted tape, ribs, combine techniques

#### **1. Introduction**

The phenomenon of heat transfer has always been a topic of interest to researchers and manufacturers alike. The previous researchers have addressed heat transfer characteristics of wide varieties of fields like bio-heat transfer, semiconductors, various cooling techniques, and natural phenomenon like oceanic currents and other important and relevant areas.

This chapter aims to cover all the relevant research papers about heat transfer published till 2018; few are there containing numerical and analytical aspects of heat transfer, while others are highlighted for its applications in engineering.
