Applications of the field synergy principle in developing new type heat transfer enhanced surfaces

In this keynote lecture, the basic idea of the field synergy principle proposed by Guo and its recent advances is first briefly reviewed, followed by detailed discussion on how to apply this principle for developing new types of heat transfer enhancement surfaces. Focus is concentrated on the enhancement of airside heat transfer processes. Four interesting examples are provided, which are the major achievements of our research group in the past 3 years. These are (1) the finding of the optimal attack angle for an array of obliquely positioned plates; (2) the development of a longitudinally finned tube with a blocked center; (3) the effect of the strip location on the enhancement of heat transfer; and (4) a new type of slotted fin surface that can significantly enhance air heat transfer while leading to only a mild increase in pressure drop. The application examples show that the field synergy principle is a powerful tool in the development of new types of heat transfer enhancement surfaces.